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Mining entity and relation from unstructured text is important for knowledge graph construction and expansion. Recent approaches have achieved promising performance while still suffering from inherent limitations, such as the computation efficiency and redundancy of relation prediction. In this paper, we propose a novel hybrid attention and dilated convolution network (HADNet), an end-to-end solution for entity and relation extraction and mining. HADNet designs a novel encoder architecture integrated with an attention mechanism, dilated convolutions, and gated unit to further improve computation efficiency, which achieves an effective global receptive field while considering local context. For the decoder, we decompose the task into three phases, relation prediction, entity recognition and relation determination. We evaluate our proposed model using two public real-world datasets that the experimental results demonstrate the effectiveness of the proposed model. [ABSTRACT FROM AUTHOR]

Exploiting dynamic spatial and temporal features of location information for robot modeling is of great importance in many real applications. It has gained increasing attention in the era of the Internet of Things (IoT). However, successful modeling and accurate localization for robot in indoor environment is still a challenge, where the environment factors are complex and unpredictable, such as signal noise, obstacles and spare fingerprints. Existing studies usually employ data driven and learning based models to capture spatial and temporal features for robot location estimation, modeling dynamics of robot and make robot decision. However, the modeling and localization performance is not satisfied. In this paper, to address above challenges, a novel deep learning framework called multi-faceted deep learning based dynamics modeling and robot localization learning (DMLoc) method is proposed. Specifically, a localization attention module is designed to capture the features from original fingerprints and optimized fingerprints information. Then, a multi-faceted localization module is proposed, which integrates extraction model and optimized model with long short-term memory (LSTM) and gate recurrent unit (GRU). Moreover, a multi-feature fusion layer is designed to fuse the extracted features and generate localization results. Extensive simulation results show the efficiency of the proposed DMLoc. [ABSTRACT FROM AUTHOR]

As an important carrier of history, ancient ceramic ware is a crucial part of the traditional Chinese culture and heritage. The porcelain ewer is a typical example of ancient Chinese ceramic ware. The shapes of the porcelain ewers from the Tang, Song, and Yuan dynasties reflect their artistic characteristics. Different shapes and characteristics reflect the cultures of different dynasties and their production processes and lifestyle. Shapes are an important feature for identifying ancient ceramics. The complex structure of a porcelain ewer makes it difficult to reflect the evolution of its overall shape with partial shape changes. In this study, digital extraction methods of shape characteristics for porcelain ewers were discussed using samples of porcelain-handled ewers from the Tang dynasty to the Song and Yuan periods. Spatial correlation weights of same-side pixels and spatial similarity weights of symmetric pixels in the digital image were calculated by affinity measurement combined with the simple linear iterative cluster normalized cut (SLIC-Ncut) algorithm to segment porcelain ewers. The shape data of the main parts were extracted for analysis and preliminary classification. The position of the spout, the position of the handle, and the centre of gravity obtained from the shape data are crucial parameters for dating its age. The conclusions obtained are consistent with the traditional identification results, which indicate that the proposed method is an effective and feasible computer-aided method for identifying porcelain ewers. [ABSTRACT FROM AUTHOR]

Finding out and turning off the radio-frequency interference (RFI) sources as many as possible is an important work for synthetic aperture interferometric radiometer (SAIR). While the impact of strong RFIs on reconstructed brightness temperature (BT) image is clearly observable, the presence of low- or moderate-level RFIs is often hard to be aware of, leaving the RFI detection and localization a difficult problem. In this article, an improved RFI detection method is proposed by making use of the point-source ripple to give prominence to the RFIs presented in the SAIR imagery. The method tests based on Soil Moisture and Ocean Salinity satellite (SMOS) visibility samples and the performance evaluations by numerical simulations validate the correctness and effectiveness of the developed method. [ABSTRACT FROM AUTHOR]

Grounding electrode is an indispensable part in HVDC transmission projects. During its design and safety evaluation, step voltage is a crucial aspect. By reviewing and sorting out the present standards involving step voltage measurement and its safety limit, this paper illustrates the contradiction between the measurement methods and the safety evaluation criteria. Reasons for the contradiction are explained by analyzing the principal of step voltage measurement and safety evaluation. The Open-circuit step voltage measurement method and the measurement method with a human body equivalent resistance paralleled are compared to find out their advantages and disadvantages. Suitable circumstances and corresponding safety criteria of these two methods are put forward. Method proposed in this paper can be applied to step voltage measurement and safety evaluation of HVDC grounding electrode, providing reference when revising the related standards. [ABSTRACT FROM AUTHOR]

In this paper, a robust observer-based sliding mode control algorithm is proposed to address the modelling and measurement inaccuracies, load variations, and external disturbances of flexible articulated manipulators. Firstly, a sliding mode observer was designed with exponential convergence to observe system state accurately and to overcome the measuring difficulty of the state variables, unmeasurable quantities, and external disturbances. Next, a robust sliding mode controller was developed based on the observer, such that the output error of the system converges to zero in finite time. In this way, the whole system achieves asymptotic stability. Finally, the convergence conditions of the observer were theoretically analyzed to verify the convergence of the proposed algorithm, and simulation was carried out to confirm the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Currently, many microwave radiometers have been successfully used in earth-observation and ocean-monitoring systems. In China, the scanning microwave radiometers (SMR) onboard the Haiyang-2A/2B (HY-2A/2B) satellites are multichannel radiometers capable of obtaining oceanic and atmospheric parameters, such as sea surface temperature (SST), sea surface wind speed (WS), water vapor (WV), and cloud liquid water (LW). As a successor to HY-2A, the HY-2B satellite was launched successfully on October 25, 2018. Compared with the HY-2A’s SMR, the HY-2B’s SMR is an improved microwave radiometer. This article is concerned with the instrument design of the HY-2B’s SMR and its improvements. The important improvements of the HY-2B’s SMR in regard to the feedhorns and cold-sky reflector (CSR) are verified, and the early in-orbit performance of the HY-2B’s SMR is evaluated. The results demonstrate that the HY-2B’s SMR exhibits an important improvement on the HY-2A’s SMR in terms of the quality of the brightness temperature (TB) products and calibration accuracy. The results also show that the HY-2B’s SMR has a good performance in terms of the global TB images and the retrieved products with a good agreement with the expectations. [ABSTRACT FROM AUTHOR]

Ship detection is important for a wide range of applications. In this article, an airborne passive interferometric microwave sensor (PIMS) is proposed as a powerful complementary tool for ship detection. The fundamental of ship detection by the airborne PIMS is introduced. A specification called “the detection factor” is addressed to quantitatively assess the performance of the airborne PIMS for ship detection. The detection probability is discussed and addressed based on the constant false-alarm rate (CFAR). Numerical simulations are performed to demonstrate the feasibility of ship detection by the airborne PIMS. The impacts of the atmosphere and the sea wind on the performance of the airborne PIMS for ship detection are also addressed in terms of theoretical analyses and numerical simulations. The airborne experiments are also carried out by an X-band PIMS to verify the practicability of ship detection by the airborne PIMS in a sunny weather and a cloudy weather. The data processing procedure and a ship detection algorithm in the experiments are introduced. The airborne experimental results reveal that the ships can be effectively detected and tracked by the airborne X-band PIMS in a sunny weather and a cloudy weather. It demonstrates the practicability of ship detection by the airborne PIMS. The ship detection probability is also analyzed, which agrees well with the theoretical detection probability. [ABSTRACT FROM AUTHOR]

With the rapid development of data center network, the traditional traffic scheduling method can easily cause problems such as link congestion and load imbalance. Therefore, this paper proposes a novel dynamic flow scheduling algorithm GA-ACO (Genetic Algorithm and Ant COlony algorithms). GA-ACO algorithm obtains the global perspective of the network under the SDN (Software defined network) architecture. It then calculates the global optimal path for the elephant flow on the congestion link, and reroutes it. Extensive experiments have been executed to evaluate the performance of the proposed GA-ACO algorithm. The simulation results show that, in comparison with ECMP and ACO-SDN algorithm, GA-ACO can not only reduce the maximum link utilization, but also improve the bandwidth effectively. [ABSTRACT FROM AUTHOR]

Geomagnetically – Induced Currents (GIC) and monopole operation of high voltage direct current (HVDC) both can cause transformer DC bias, and Jiles-Atherton (JA) model is effective in transformer DC bias simulation while the influence of initial magnetization is neglected in existing papers. In this paper, the influence of initial magnetization and magnetizing current on simulation process are analysed based on the presented simulation model, and the conclusion that initial magnetization has evident influence while initial magnetizing current has not is reached. The trend of magnetizing current is valued by representative slope of envelop curve, then an improved secant method for getting proper initial magnetization is proposed basing on the slope. With the method, the dependence of proper initial magnetization on DC current and closing angle are presented, and the mechanization is analysed. [ABSTRACT FROM AUTHOR]

Soil sparkover is one of the key factors that affect the impulse characteristics of grounding devices under lightning current. In this study, the polyester‐based sensitive films are applied to observe the morphology features of the sandy sparkover around a horizontal grounding rod 1 m in length buried in a hemispheric pool 8 m in diameter under impulse current. Moreover, the releasing current distribution of the grounding rod is measured by modular multi‐channel simultaneous signal acquisition system. Along with injected impulse current increasing, the ratio of current released from two ends of the rod increases because the spark discharge leads the redistribution of the dissipating current. The discharge in the sand becomes more intense with current increasing. The discharge on middle segments spreads around the electrode‐like cluster, while sparkover at the terminal develops into tree creeping discharge finally. Analysis based on combining observation images with current measurement result suggests that sparkover morphology is related to not only electric field value but also electric field distribution. The sparkover strength is determined by electric field intensity, while the sparkover concentration depends on electric field uniformity. [ABSTRACT FROM AUTHOR]

Abstract: The volatilization behavior of chlorine in three Chinese bituminous coals during pyrolysis and CO2-gasification in a fluidized bed reactor was investigated. The modes of occurrence of chlorine in raw coals and their char samples were determined using sequential chemical extraction method. The Cl volatility increases with increasing temperature. Below 600°C the Cl volatility is different, depending on the coal type and the occurrence mode of Cl. Above 700°C, the Cl volatilities for the three coals tested are all higher than 80%. About 41% of the chlorine in Lu-an coal and 73% of that in Yanzhou coal are organic forms, and most of them are covalently-bonded organic chlorine, which shows high volatile behavior even at low pyrolysis temperatures (below 500°C), while the inorganic forms of chlorine in two coal samples are hardly volatilized even at low pyrolysis temperatures (below 400°C). The restraining efficiency of addition of CaO on chlorine volatility is greatly dependent on pyrolysis temperature. The optimal restraining efficiency can be obtained at temperature range from 450 to 650°C during pyrolysis of Lu-an coal. The volatile behavior of Cl is mainly dependent on temperature. Above 700°C high volatility of Cl is obtained in both N2 and CO2 atmospheres. [Copyright &y& Elsevier]

Abstract: The volatilization behavior of fluorine in five Chinese coals was investigated during fluidized-bed pyrolysis and CO2-gasification at a temperature range of 500–900°C. The effect of co-existed and added calcium on fluorine volatility during pyrolysis was also determined. With increasing pyrolysis temperature, the volatility of fluorine increases. However, the volatility is greatly dependent on the fluorine chemical forms occurred in coal. Except for Datong and Zhungeer coal, more than 65% of fluorine in other three coals occurs as the steady forms. Fluorapatite is not the major carrier of fluorine in the coals studied. Fluorine volatility is retarded by coexisting calcium during coal pyrolysis, indicating that at least part of the stable forms of fluorine in coal might occur as calcium fluoride or calcium fluoride with complex compounds which are stable even at high pyrolysis temperature. The addition of CaO and limestone can suppress the release of fluorine during pyrolysis. The effect of CaO is better than that of limestone. The volatility of fluorine of coal during CO2-gasification depends on not only the occurrence mode of fluorine, but also the gasification reactivity of the coal. Compared with N2 atmosphere, CO2 is more favorable to the release of fluorine from coal. [Copyright &y& Elsevier]

Arsenic is one of the most concerned trace elements in coal because of its toxicity and environmental persistence. Little information about the transformation behavior of arsenic under pyrolysis conditions was reported. In this paper, the volatilization behavior of arsenic and the influence of coexisting mineral matters and additive CaO were investigated during pyrolysis of Yima coal in a fluidized-bed reactor at temperatures ranging from 350 to 900 °C. The modes of occurrence of arsenic in Yima raw coal and its two char samples are determined using four methods including density fractionation, demineralization, X-ray diffraction (XRD) and sequential chemical extraction. It is found that arsenic in Yima coal is mainly associated with pyrite, and changes greatly during coal pyrolysis. Staged volatility behavior of arsenic is observed during Yima coal pyrolysis. From 350 to 500 °C, arsenic volatility increases with increasing temperature, while it changes little from 500 to 800 °C. Arsenic behavior in YimaD (demineralized sample of Yima) and CaO additive reveal that the vaporization of arsenic in Yima coal during pyrolysis is retarded by its coexisting mineral matters or added CaO to form thermally stable forms of arsenic. These forms might be generated through the formation of As–Ca complexes such as calcium arsenate, or through absorption and capture reactions with aluminosilicate mineral matters and trapped into their lattices. [Copyright &y& Elsevier]

The volatilization behavior of Pb, Cd, Cr and the influence of coexisting mineral matters were investigated during pyrolysis of Yima coal in a fluidized-bed reactor at temperatures ranging from 500 to 900 °C. The modes of occurrence of Pb, Cd, Cr in Yima raw coal and two char samples were determined using density fractionation, demineralization and sequential chemical extraction methods. Lead in Yima coal is mostly associated with mineral matter in various forms, mainly pyrite, sulfates and monosulfides. Large part of cadmium is associated with pyrite. Chromium in Yima coal is mainly associated with organic matter. Different trends are observed for various forms of trace metals during pyrolysis. Lead associated with pyrite, sulfates and carbonates, lead in water soluble and ion exchangeable forms, and cadmium associated with pyrite are all unstable under pyrolysis conditions. During Yima coal pyrolysis, the volatilities of lead and cadmium vary greatly with pyrolysis temperature, while chromium volatility in Yima raw coal only has slight changes over the temperature range (500–900 °C) studied. The volatility of Pb, Cd, Cr in demineralized Yima coal (YimaD) is much higher than that of Yima coal during pyrolysis. New thermally stable forms of Pb, Cd and Cr are formed during pyrolysis of Yima, whereas the sources of them are different. The interactions between chromium and its coexisting mineral matters in Yima coal retard its vaporization during pyrolysis. [Copyright &y& Elsevier]

• The soil resistivity model obtained by the conventional soil resistivity measurement method cannot reflect the actual temperature rise of deep-well earth electrodes. • For HVDC deep-well earth electrodes, the soil resistivity near the electrodes has a large effect on its temperature rise. • The local soil resistivity model is established to calculate the temperature rise of the earth electrode through the apparent resistivity logging data. • Simulation and experiments show that the soil resistivity model proposed in this paper can achieve higher accuracy. Deep-well DC earthing electrode occupied much smaller area than the traditional one, which greatly reduce the difficulty of site selection. However, due to the extremely high current density at the end of linear earthing electrode, temperature rise has become an important factor restricting the development of deep-well earthing technology. In order to evaluate the heating situation of deep-well earthing electrode in an accurate way, this paper carried out the field temperature rise test of deep-well earthing electrode, and the error between the temperature rise result calculated by the wide-area soil resistivity model obtained by conventional measurement methods are analyzed. It was found that the local soil resistivity near the deep-well earthing electrode determines the temperature rise characteristic. Based on the fitting results of the apparent resistivity logging, a local soil resistivity modeling method suitable for deep-well earthing electrode temperature rise calculation is proposed, and the deep-well earthing electrode temperature rise calculation model considering temperature characteristics of water-saturated underground medium and local soil model is established. The calculation result of this model is used to compare with the field measured data of the temperature rise in actual projects, and the maximum temperature error is found to be 5.5 °C. The trend of electrode temperature rise is in good agreement with the test results, which explains the special phenomenon of high temperature rise in low resistance layer. Project cases prove the effectiveness and accuracy of the soil modeling and temperature rise simulation method proposed in this paper. [ABSTRACT FROM AUTHOR]

The impulse performance of grounding electrodes highly depends on soil impulse discharge characteristics. The analysis of soil discharge dynamic process images is helpful to understand the impulse discharge mechanism of grounding electrodes. This paper designed an optical‐electrical synchronous observation platform for simulate soil (SiO2 crystal) discharge, and discharge dynamic process images is obtained by high‐speed camera. Through analysing breakdown delay time and thermal power before breakdown, it is found that soil impulse discharge is mainly an electrical breakdown process, and soil ionization intensity is positively correlated with the light intensity emitted by whole soil sample in breakdown channel development stage. The time from voltage application to the occurrence of ionization is defined as initial ionization delay time (IIDT). Using image processing technology, the change curve of optical image average grayscale value with time in the process of soil discharge is obtained, and a calculation method of IIDT is proposed by comparing the difference between average grayscale value curve and background image average grayscale value. Experiment results show that IIDT is negatively correlated with impulse voltage, particle size and water content, but not with salt content. [ABSTRACT FROM AUTHOR]

Glycyrrhetinic acid (GA) is a saponin compound, isolated from licorice (Glycyrrhiza glabra), which has been wildly explored for its intriguing pharmacological and medicinal effects. GA is a triterpenoid glycoside displaying an array of pharmacological and biological activities, including anti-inflammatory, anti-bacterial, antiviral and antioxidative properties. In this study, we investigated the underlying mechanisms of GA on acne vulgaris through network pharmacology and proteomics. After the intersection of the 154 drug targets and 581 disease targets, 37 therapeutic targets for GA against acne were obtained. A protein–protein interaction (PPI) network analysis highlighted TNF, IL1B, IL6, ESR1, PPARG, NFKB1, STAT3 and TLR4 as key targets of GA against acne, which is further verified by molecular docking. The experimental results showed that GA inhibited lipid synthesis in vitro and in vivo, improved the histopathological damage of skin, prevented mast cell infiltration and decreased the level of pro-inflammatory cytokines, including TNF-α, IL-1β and IL-6. This study indicates that GA may regulate multiple pathways to improve acne symptoms, and the beneficial effects of GA against acne vulgaris might be through the regulation of sebogenesis and inflammatory responses. [ABSTRACT FROM AUTHOR]

This paper explores deep into the collaborative scheduling of common rail dual automatic guided vehicles (AGVs). Firstly, a dual AGV scheduling model was constructed to minimize the overall time of material distribution. Then, a novel scheduling algorithm was developed to dynamically plan the orders based on time windows. To effectively minimize the distribution time, heuristic algorithms were adopted to initialize the distribution order of materials. On this basis, the collaboration between the two AGVs was innovatively designed based on dynamic planning and time windows, making up for the defects of traditional methods in AGV cooperation. This greatly shortens the running time of the entire system in material distribution. The computing results fully demonstrate the efficiency and rationality of our algorithm. Finally, our algorithm was proved to be superior to the benchmark method through experiments on actual industrial instances. [ABSTRACT FROM AUTHOR]

When the traditional C4.5 algorithm deals with the big data with a large number of multidimensional continuous attribute values, it may cause the issue of low classification accuracy with the related discretization method. This paper proposes a novel method to discretize continuous data based on the k-means algorithm. The method generates data clusters by combining continuous, unfeatured data with corresponding class labels, and then takes the approximate boundary points of the cluster as the candidate splitting-points of the continuous attribute. Based on this, the information gain ratio is calculated. Experimental results show that, the proposed K-C4.5 algorithm improves the classification accuracy of the decision tree in comparison with the traditional one. [ABSTRACT FROM AUTHOR]

During monopolar operation or commissioning of high-voltage direct-current (HVdc) links, ground-return current (GRC) leads to power transformer dc bias issues. A GRC model is proposed in this paper, and the penetration depth, penetration ratio, and earth surface potential of various earth models are simulated. The result indicates that the influence of deep earth resistivity increases rapidly by the increasing distance from substations to HVdc electrodes. The simulation results are compared with measured data of GRCs distribution in the Hubei power grid of China. The result demonstrates that the simulation considering deep earth resistivity is credible and the shallow earth model could lead to poor accuracy. Furthermore, earth resistivity measurements are carried out at different geological regions and the deep earth characteristics and the GRCs distribution are quite different. Thus, it can be concluded that to calculate GRCs distribution using uniform earth structure without measurement is not appropriate. Finally, the relationship between accurately measured earth depth and the accuracy ratio of GRCs calculation is analyzed. The result of this paper contributes to determine the depth of earth model in GRCs simulation modeling and earth resistivity measurements. [ABSTRACT FROM AUTHOR]

The spark discharge in the soil is a key factor that affects the impulse characteristics of grounding devices under the lightning current. However, since soil is inhomogeneous medium consisted with humid‐air, ionic liquid, and soil particles, the developing process of the soil sparkover is very complicated. In this study, the polyester‐based sensitive films are used to observe the morphology features of the soil sparkover in the plate electrodes. According to the observed images, the spark discharge in the soil can be divided into partial discharge and arc discharge. The change of instantaneous resistance can be explained by the three stages of soil ionisation/deionisation. Moreover, the distinct images of the sparkover around the rod electrode buried horizontally in the grounding pool are obtained by the proposed method. The distribution of discharge points, developing process, and feature of the soil sparkover are analysed. [ABSTRACT FROM AUTHOR]

Soil ionisation has an important influence on impulse characteristics of grounding conductor. This paper introduced improvements to an existing soil ionisation model considering the influence of electric field on the change of soil resistivity, while soil resistivity is not directly dependent on soil electric field. The validity of improved soil ionisation model was verified by surge response of vertical conductor in uniform soil and horizontally stratified soil. Furthermore, the impulse experiment was carried out on horizontal conductor in soil with finite volumes. Based on experimental configuration, the corresponding calculation model was built, and calculated results were in good agreement with experimental results. [ABSTRACT FROM AUTHOR]

The uniqueness of DC deep-well ground electrodes (DWGEs) lies in their low area requirements. However, the gas produced by DWGEs during electrolysis may cause more severe exhaust problems than those caused by conventional electrodes. To investigate the influence of different electrode materials on the gas evolution of DWGEs, an innovative U-shaped experimental platform is proposed for the separate collection of cathode and anode gases. The metal–electrolyte contact interface in a DWGE project was simulated, and gas evolution experiments were performed on three typical ground electrode materials. The gas evolution rates of the electrode materials when operate as cathodes and anodes were obtained. Polarization curves were used to compare the corrosion rates of the three materials and evaluate the effects of these rates on the gas evolution rates of the materials. The results revealed that when operated as anodes, mixed metal oxide (MMO) and high-silicon cast iron produced oxygen, whereas carbon steel did not. Furthermore, the evolution of O2 in MMO was faster than that in high-silicon cast iron. When operated as cathodes, the three materials generated hydrogen, and carbon steel exhibited the slowest H2 evolution rate. The current distribution in the different gas evolution processes was summarized. The supplied current was used as the reaction current of metal corrosion and for gas generation. Under the same current, quicker corrosion corresponded to a lower amount of gas evolution for a material. [ABSTRACT FROM AUTHOR]

Radio frequency interference (RFI) has become an increasing and challenging problem in microwave interferometric radiometry (MIR). Accurate localization of RFI sources is helpful to provide location information for switching off unauthorized transmitters causing RFI and mitigating the impact of these RFI sources. In this article, we propose a new RFI localization method based on reweighted nuclear norm minimization (RNNM). This method exploits the low-rank property of augmented covariance matrix (ACM) collecting visibility samples in MIR and introduces a singular value weighting strategy to consider different contributions of ACM components. First, ACM is constructed from the original covariance matrix of sparse array, which increases the degree of freedom (DOF) for array processing and hence improves the angular resolution performance. Second, we present a fixed point iteration (FPI)-based RNNM Algorithm, named FRA, to achieve low-rank approximation of ACM involving contribution degrees of ACM components. In this way, the ACM components corresponding to RFI signals are retained well and ones corresponding to background noises are suppressed. Third, we use a subspace-based direction-of-arrival (DOA) estimation approach, i.e., MUSIC algorithm, on the weighted completed ACM (WCACM) (obtained by FRA in the second stage) to locate the potential RFI sources. Retrieved results using synthetic data and real soil moisture and ocean salinity (SMOS) satellite data demonstrate that the proposed RNNM-based method not only has the superiority on improved detection performance, especially for identifying weak sources, but also shows better or competitive localization accuracy and angular resolution, compared with the existing commonly used RFI localization methods in MIR. [ABSTRACT FROM AUTHOR]

Abstract: Due to the importance of pancreatic cholesterol esterase (CEase) as a potential target in atherosclerosis and for the development of hypocholesterolemic agents, there are increasing interests in designing and synthesizing CEase inhibitors. In the present study, we prepared forty-five isocoumarin phosphorus analogues (i.e., phosphaisocoumarins) and investigated the inhibition of these compounds on the CEase. The results showed that some phosphaisocoumarins could act as potent inhibitors of CEase. The most potent inhibitors, compounds 9d, 10a and 12e give IC50 values of 4.8 μM, 2.3 μM and 1.9 μM, respectively. The inhibition mechanism and kinetic characterization studies indicate that they are reversible competitive inhibitors. [Copyright &y& Elsevier]

Radiometric sensitivity is crucially important for microwave interferometric radiometers. To pursue optimum performance of radiometric sensitivity, the minimum-degradation arrays (MDAs) or low-degradation arrays (LDAs) are usually employed. In this article, we propose a deterministic method for designing low-degradation linear arrays (LDLAs), which exploits the multiple-fold redundancy property of baseline coverage (i.e., $u$ – $v$ coverage) of interferometric arrays and further devises analytical patterns for closed-form geometric construction. The proposed method can not only attain LDLAs with satisfactory radiometric sensitivity in significantly low computational complexity, given any number of sensor elements, but also has easy adoption on large array synthesis and configuration expansion scenarios. In addition, such analytically designed LDLAs also have the advantage of array robustness (or system reliability) in the sense of $u$ – $v$ coverage shrinking and “hole” occurrence (resulted from sensor failures). Numerical results are given to demonstrate the effectiveness of the proposed LDLA design method through comparison with stochastic algorithms based on heuristic search and combinatorial approaches uniting specific integer sequences, e.g., cyclic difference sets. [ABSTRACT FROM AUTHOR]

We set up a tripartite entangled state representation |p, χ[sub 2], χ[sub 3]> in three-mode Fock space which is composed of the common eigenvectors of three particles' relative coordinates X[sub 1] - X[sub 2] and X[sub 1] - X[sub 3] as well as the total momentum P[sub 1] + P[sub 2] + P[sub 3]. The Schmidt decomposition of |p, χ[sub 2], χ[sub 3] > is made and its application in quantum teleporting a two-particle entangled state or a two-mode squeezed state is analyzed. [ABSTRACT FROM AUTHOR]

Due to the impedance characteristic of conductor, the ground potential rise is different within grounding grid when impulse current is injected. When staff touches objects with different GPR at the same time, the GPD will be applied to human body, leading to potential personal safety problem. The impact of GPD on human body needs to be evaluated. The method of moment was used to calculate the ground potential rise of grounding grid under impulse current. By regarding the human body as a resistance, the current flowing through it because of ground potential difference was obtained. Methods based on current amplitude and electrical charge was used to evaluate personal safety. The effects of injecting current waveform, injecting position, soil resistivity, grounding conductor and grounding grid structure on ground potential difference and safe current threshold were studied. Results show the ground potential difference near injecting point may pose a threat to personal safety. The evaluation method based on electrical charge was recommended. In field test, the injecting point of grounding grid should be far away from corners, and staff should be kept away from the injecting point, so as to mitigate the risk of ground potential difference on personal safety. [ABSTRACT FROM AUTHOR]

Background: Veratrum nigrum (Liliaceae) is perennial medicinal plant widely used to treat various conditions. To determine its insecticidal properties against the German cockroach (Blattella germanica), several laboratory tests were carried out. Methods: A 4kg dry sample of V. nigrum root was purchased from the medicinal material market in Yunnan Province in 2015, China. In contact toxicity tests, V. nigrum alkaloidal extract was topically applied to the abdomen of cockroaches using a micro-applicator. In vitro acetylcholinesterase (AChE) activity tests were performed using a modified Ellman method. Results: Veratrum nigrum alkaloidal extract was toxic to male adults and 4th nymphs cockroaches, with median lethal dose (LD50) values of 14.90μg/insect, 14.21μg/insect for adults and 41.45μg/insect, 39.01μg/insect for 4th nymphs after 24h and 48h exposure, respectively. There was a significant difference between adults and nymphs in terms of tolerance to V. nigrum alkaloidal extract. There was no significant difference in mortalities at 24h and 48h, the lethal effect of V. nigrum alkaloidal extract on German cockroach was quick. AChE activity tests showed that V. nigrum alkaloidal extract had an excellent inhibitory effect on AChE: inhibition in the 4th nymphs and male adults had 50% inhibiting concentration (IC50) values of 3.56mg/ml and 5.78mg/ml respectively. The inhibitory effect of AChE activity was positively correlated with inhibitory time (0–20min), at a concentration of 1mg/ml, inhibition of nymph and adult AChE activity had 50% inhibiting time (IT50) values of 8.34min and 16.75min, respectively. Conclusion: V. nigrum may be explored as a potential natural insecticide for control of the German cockroach. [ABSTRACT FROM AUTHOR]

Space-time consistency is of great importance for mapping things from physical world to cyber world, which could be one of the fundamental issues in constructing cyber-physical system (CPS). A two-dimensional code spatiotemporal modeling method is proposed in this paper. We apply the two-dimensional code as an information carrier to store object’s characteristics (object’s ID, attributes, instructions, spatiotemporal data, etc.), the smartphone as a mobile device to obtain the object’s real-time spatiotemporal data with its system time and GPS module; then the object’s spatiotemporal information can be transmitted and stored in a backend server with a database. Meanwhile, the object’s spatiotemporal information can also be inquired by smartphone users and other web users. A use case that applied this proposed method to trace object’s smartphone information is described later, and the result shows that tracing objects with two-dimensional code has many advantages, such as fast reading and transmitting, low cost, and robust, confidential, and strong readability; furthermore, the proposed modeling method keeps the consistency of object’s time and space in CPS. [ABSTRACT FROM AUTHOR]

Knowledge of impulse characteristics of tower grounding devices is important for lightning protection of the transmission lines. In this paper, the time-domain difference method is proposed to analyze the impulse characteristics of tower grounding devices. Combined with the soil ionization model and the soil-critical breakdown field strength, the proposed method is capable of modeling nonlinear ionization of the soil. The voltage-response waveform calculated by the proposed method is smooth, which is superior to the waveform calculated by the frequency-domain numerical algorithm. The reduced-scale experiments of grounding devices with different structures were carried out in the laboratory to validate the accuracy of the proposed method. Furthermore, the critical breakdown field strength used in the soil ionization model is measured by the coaxial cylindrical electrodes. [ABSTRACT FROM AUTHOR]

• Water-saturated soil resistivity decreases exponentially with rising temperature. • An electro-thermal coupled FEM model is established using the obtained function. • The experiment proved that model can reach high accuracy for water-saturated soil. The temperature rise process has always been the main factor for the safe operation of high-voltage direct current (HVDC) grounding electrodes, and the soil resistivity is the key parameter affecting the temperature rise of the grounding electrode. In some region where rainfall is high or groundwater is abundant, the soil moisture content at the electrode site may be very high or saturated. Therefore, studying the temperature characteristics of soils with saturated water content (water-saturated soil) for grounding electrode heating is particularly important. In this study, the resistivity measurement of temperature rise was conducted on different types of water-saturated soil. On the basis of this measurement result, an electro-thermal coupling finite element model of grounding electrode in water-saturated soil was established. Then the reliability of the coupled model is verified through an experiment of the vertical electrode in water-saturated soil. The comparison of experimental and simulation results shows that the maximum temperature error is 3.5%. Finally, the influence of water-saturated soil resistivity on practical engineering application was analyzed. Under the condition of water-saturated soil, the saturation of electrode temperature rise curve gets more pronounced as the current injection time increases. Thus, the temperature rise rate of the actual grounding electrode is lower than the calculation result without considering the water-saturated soil resistivity. Therefore, using the temperature characteristics of water-saturated soil resistivity to simulate the temperature rise of the grounding electrode can provide a theoretical basis for the grounding electrode to work under water-saturated soil conditions. [ABSTRACT FROM AUTHOR]

Radio Frequency Identification (RFID) is one of the key areas of the internet of things (IoT) and widely used in the fields of target identification, security, tracking, anticounterfeiting, and so forth. In some IoT scenario, multilevel package is used to pack the products. The RFID codes of different-level packages imply the subordinate relation. Based on this relation, we can directly obtain the sublevel package code by a package code. It will greatly improve the efficiency of logistics management, especially assisting the tracking and tracing of merchandise. In this paper, a RFID code scheme is introduced to identify different-level packages. With research on the relation of multilevel packages, the subordinate relation of different-level RFID codes is established by recording and storing the inclusion relation between codes in the database. Moreover, the code scheme is applied in Fast Moving Consumer Goods (FMCG) management, which is an example of three-level packages, to verify its feasibility. [ABSTRACT FROM AUTHOR]