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The Industrial Metaverse provides unparalleled prospects for increasing productivity and efficiency across multiple sectors. As wireless sensor networks play an important role in data collection and transmission within this ecosystem, preserving context privacy becomes critical to protecting sensitive information. This paper investigates the issue of context privacy preservation for user validation via AccesSensor in the Industrial Metaverse and presents a technological method to address it. We explore the need for context privacy, look at existing privacy preservation solutions, and propose novel user validation methods that are customized to the Industrial Metaverse's access system. This method is evaluated on time-based efficiency, privacy method and bandwidth utilization. Our method performs better as compared to the DPSensor. Our research seeks to provide insights and recommendations for developing strong privacy protection methods in wireless sensor networks that operate within the Industrial Metaverse ecosystem. [ABSTRACT FROM AUTHOR]

Accretion of black holes at near-Eddington or super-Eddington rates represents the most powerful episode driving black hole growth, potentially occurring across various types of objects. However, the physics governing accretion and jet–disk coupling in such states remains unclear, primarily due to the difficulty in detecting associated jets, which may emit extremely weakly or exhibit episodic behavior. Only a few near/super-Eddington systems have demonstrated radio activity, and it remains uncertain whether jets exist and what their properties are in super-Eddington active galactic nuclei (AGNs) and ultraluminous X-ray sources. This uncertainty stems mainly from the complex radio emission mix, which includes contributions from jets, star formation activity, photoionized gas, accretion disk wind, and coronal activity. In this work, we conducted high-resolution, very long baseline interferometry observations to investigate jets in the highly accreting narrow-line Seyfert I system I Zw 1. Our observations successfully revealed small-scale jets (with a linear size of ∼45 pc) at both 1.5 and 5 GHz, based on the high radio brightness temperature, radio morphology, and spectral index distribution. Additionally, the parsec-scale jet observed in I Zw 1 displays a knotted morphology reminiscent of other sources accreting at similar rates. In summary, the high accretion rates and jet properties observed in the AGN I Zw 1 may support the AGN/X-ray binary analogy in this extreme state. [ABSTRACT FROM AUTHOR]

[Display omitted] Healable electronic skins, an essential component for future soft robotics, implantable bioelectronics, and smart wearable systems, necessitate self-healable and pliable materials that exhibit functionality at intricate interfaces. Although a plethora of self-healable materials have been developed, the fabrication of highly conformal biocompatible functional materials on complex biological surfaces remains a formidable challenge. Inspired by regenerative properties of skin, we present the self-assembled transfer-printable liquid metal epidermis (SALME), which possesses autonomous self-healing capabilities at the oil–water interface. SALME comprises a layer of surfactant-grafted liquid metal nanodroplets that spontaneously assemble at the oil–water interface within a few seconds. This unique self-assembly property facilitates rapid restoration (<10 s) of SALME following mechanical damage. In addition to its self-healing ability, SALME exhibits excellent shear resistance and can be seamlessly transferred to arbitrary hydrophilic/hydrophobic curved surfaces. The transferred SALME effectively preserves submicron-scale surface textures on biological substrates, thus displaying tremendous potential for future epidermal bioelectronics. [ABSTRACT FROM AUTHOR]

We present radio very long baseline interferometry (VLBI) and X-ray studies of the starburst galaxy NGC 3628. The VLBI observation at 1.5 GHz reveals seven compact (0.7−7 pc) radio sources in the central ∼250 pc region of NGC 3628. Based on their morphology, high radio-brightness temperatures (105–107 K), and steep radio spectra, none of these seven sources can be associated with active galactic nuclei (AGNs); instead, they can be identified as supernova remnants (SNRs), with three of them appearing consistent with partial shells. Notably, one of them (W2) is likely a nascent radio supernova (SN) and appears to be consistent with the star formation rate of NGC 3628 when assuming a canonical initial mass function. The VLBI observation provides the first precise measurement of the diameter of the radio sources in NGC 3628, which allow us to fit a well-constrained radio surface brightness—diameter (Σ– D) correlation by including the detected SNRs. Furthermore, future VLBI observations can be conducted to measure the expansion velocity of the detected SNRs. In addition to our radio VLBI study, we analyze Chandra and XMM-Newton spectra of NGC 3628. The spectral fitting indicates that the SNR activities could well account for the observed X-ray emissions. Along with the Chandra X-ray image, it further reveals that the X-ray emission is likely maintained by the galactic-scale outflow triggered by SN activities. These results provide strong evidence that SN-triggered activities play a critical role in generating both radio and X-ray emissions in NGC 3628. [ABSTRACT FROM AUTHOR]

This article presents a dual‐band filtering power amplifier (DB‐FPA) with extended passband bandwidths and wide stopband rejection, which is helpful in reducing the number of microwave components in the dual‐band radio frequency front end, resulting in compact circuit size and low loss. In the designed DB‐FPA, a wideband low‐pass filter is applied as the input matching network (IMN) to provide wideband impedance matching and good stopband rejection, while a dual‐band filtering impedance transformation is adopted as the output matching network (OMN) to provide dual‐band impedance matchings and filtering responses simultaneously. Specifically, the IMN is constructed by high‐impedance transmission‐line sections and low‐impedance open‐circuit stubs. The OMN is designed based on the specific external quality factors and coupling coefficients during two bands, resulting in dual‐band impedance transformations and dual‐band filtering responses. Then, based on the above IMN and OMN, the design procedure of the presented DB‐FPA is summarised. To verify the proposed idea, a novel DB‐FPA has been fabricated and measured. During the two frequency bands, the measured maximum power added efficiencies are 55.11% and 47.78% within 33.0 dBm input power, while the measured peak gains are 15.4 and 14.0 dB within 15.0 dBm input power. [ABSTRACT FROM AUTHOR]

In recent years, the behavior recognition technology based on Wi-Fi devices has been favored by many researchers. Existing Wi-Fi-based human behavior recognition technology mainly uses classification algorithms to construct classification models, which has problems such as inaccurate behavior segmentation, failure to extract deep-level features from the original data and design classification models matching the proposed features in the process of behavior recognition. In order to solve above problems, this paper proposes a window variance comparison method by combining the adaptive thresholds calculated to achieve effective segmentation of multiple discontinuous human behaviors, then uses the short-time Fourier algorithm to extract time-frequency features of individual behavior, and extracts the graph structure data from the autocorrelation matrix of time-frequency features and the features themselves. A graph neural network is built for behavior recognition. The experimental results show that the segmentation accuracy of the behavior segmentation method in the two scenes is 0.964 and 0.993, which is better than the existing threshold-based behavior segmentation methods. In addition, this paper extracts graph structure data by spectral energy change method and builds behavior recognition model by using graph neural network, and the recognition accuracy is significantly improved compared with the traditional classification algorithm. [ABSTRACT FROM AUTHOR]

Sensor fusion is a technique that combines information from multiple sensors in order to improve the accuracy and reliability of the data being collected. In the context of teleoperation control of an anthropomorphic robotic arm, sensor fusion technology can be used to enhance the precise control of anthropomorphic robotic arms by combining data from multiple sensors, such as cameras, data gloves, force sensors, etc. By fusing and processing this sensing information, it can enable real-time control of anthropomorphic robotic arms and dexterous hands, replicating the motion of human manipulators. In this paper, we present a sensor fusion-based teleoperation control system for the anthropomorphic robotic arm and dexterous hand, which utilizes a filter to fuse data from multiple sensors in real-time. As such, the real-time perceived human arms motion posture information is analyzed and processed, and wireless communication is used to intelligently and flexibly control the anthropomorphic robotic arm and dexterous hand. Finally, the user is able to manage the anthropomorphic operation function in a stable and reliable manner. We also discussed the implementation and experimental evaluation of the system, showing that it is able to achieve improved performance and stability compared to traditional teleoperation control methods. [ABSTRACT FROM AUTHOR]

An indoor vibrational dissolution scouring test was designed to investigate the effects of vibrational frequency, vibrational acceleration, environmental temperature, and dissolution medium on the dissolution characteristics of cement-stabilized macadam base material during water erosion. The results showed that the dissolution damage effect exists in cement-stabilized macadam, and dissolution is an important evaluation index of its base failure. The amount of calcium ion (Ca2+) dissolution and pH of cement stabilized gravel increased with increasing vibrational time. When the vibrational frequency was in the range of 80–180 Hz , the amount of dissolved Ca2+ and the pH of the solution first increased, and then decreased with the vibrational frequency. The Ca2+ concentration and pH of the solution reached their maximum at 140 Hz for 10 h. Of the four vibrational dissolution factors considered, vibrational acceleration produced the largest degree of dissolution of cement-stabilized macadam. The leached Ca2+ concentration increased with increasing temperature of the dissolution medium and the concentration of ammonium chloride (NH4Cl) solution, while increasing pH decreased dissolution. [ABSTRACT FROM AUTHOR]

The optimal supplementation of lipid nutrients in the diet showed crucial physiological functions in gonadal development and maturation in adult female aquatic animals. Four isonitrogenous and isolipidic diets with no extra lecithin supplementation (control), 2% soybean lecithin (SL), egg yolk lecithin (EL), or krill oil (KO) supplementation were formulated for Cherax quadricarinatus (72.32 ± 3.58 g). Ovary development and physiological characteristics of crayfish were evaluated after a 10-week feeding trial. The results indicated that SL, EL, or KO supplementation all significantly increased the gonadosomatic index, especially in the KO group. Crayfish fed the diet with SL showed the highest hepatosomatic index compared with those fed the other experimental diets. KO was more efficient than SL and EL in promoting triacylglycerol and cholesterol deposition in the ovary and hepatopancreas but also showed the lowest concentration of low-density lipoprotein cholesterol in the serum. KO significantly increased yolk granule deposition and accelerated oocyte maturation than other experimental groups. Furthermore, dietary phospholipids significantly enhanced the gonad-stimulating hormone concentration in the ovary and reduced the secretion of gonad-inhibiting hormones in the eyestalk. KO supplementation also significantly improved organic antioxidant capacity. From the ovarian lipidomics results, phosphatidylcholine and phosphatidylethanolamine are two main glycerophospholipids that respond to different dietary phospholipids. Polyunsaturated fatty acids (especially C18:2n-6, C18:3n-3, C20:4n-6, C20:5n-3, and C22:6n-3) were pivotal participants during ovarian development of crayfish regardless of lipid type. Combined with the ovarian transcriptome, the best positive function of KO was due to activated steroid hormone biosynthesis, sphingolipid signaling, retinol metabolism, lipolysis, starch and sucrose metabolism, vitamin digestion and absorption, and pancreatic secretion. As a consequence, dietary supplementation with SL, EL, or KO all improved the ovarian development quality of C. quadricarinatus, especially KO, which was the optimum choice for promoting ovary development in adult female C. quadricarinatus. [ABSTRACT FROM AUTHOR]

We conducted a Very Long Baseline Array (VLBA) observation of the low mass active galactic nucleus (AGN) in galaxy NGC 4293 (z  = 0.003). The object is associated with a low-ionization nuclear emission-line region (LINER). Its black hole mass is estimated as ∼105 or |${\sim}10^7 \, \mathrm{M}_\odot$|⁠. The VLBA 1.5 GHz image shows an inverse symmetric structure with two discrete radio blobs separated by an angular distance of ∼120 mas, corresponding to ∼7 parsec. Furthermore, its integrated radio spectrum has a turnover at the frequency of ∼0.44 GHz. Based on the compactness and spectrum, the nuclear radio source in NGC 4293 belongs to a sample of (megahertz) peaked spectrum (PS/MPS) radio sources with compact symmetric morphologies. NGC 4293 has 1.4 GHz radio power of only |${\sim}10^{20}\, \mathrm{W\, Hz^{-1}}$| with the VLBA observation, which is consistent with local AGNs but lower than the current PS samples. One of the two blobs has a steep radio spectrum α = −0.62 ± 0.08 (S ν ∝ ν+α), while the other one has an inverted spectrum α = 0.32 ± 0.10. The VLBA 1.5 GHz luminosity ratio of the two blobs is 3.23 and both blobs show lateral-flowing structures where the hotspots reside at the edge of each radio lobe. This can be explained as jet interactions with dense circumnuclear medium. We estimate the black hole mass of NGC 4293 through the Fundamental Plane of black hole activity, which constrains the black hole mass to be |${\lesssim}10^6\, \mathrm{M}_\odot$|⁠. It supports that the object is a low-mass AGN and a potential candidate for accreting and ejecting IMBHs. [ABSTRACT FROM AUTHOR]

Gossypol is a polyphenolic toxic secondary metabolite derived from cotton. Free gossypol in cotton meal is remarkably harmful to animals. Furthermore, microbial degradation of gossypol produces metabolites that reduce feed quality. We adopted an enzymatic method to degrade free gossypol safely and effectively. We cloned the gene cce001a encoding carboxylesterase (CarE) into pPICZαA and transformed it into Pichia pastoris GS115. The target protein was successfully obtained, and CarE CCE001a could effectively degrade free gossypol with a degradation rate of 89%. When esterase was added, the exposed toxic groups of gossypol reacted with different amino acids and amines to form bound gossypol, generating substances with (M + H) m/z ratios of 560.15, 600.25, and 713.46. The molecular formula was C27H28O13, C34H36N2O6, and C47H59N3O3. The observed instability of the hydroxyl groups caused the substitution and shedding of the group, forming a substance with m/z of 488.26 and molecular formula C31H36O5. These properties render the CarE CCE001a a valid candidate for the detoxification of cotton meal. Furthermore, the findings help elucidate the degradation process of gossypol in vitro. [ABSTRACT FROM AUTHOR]

NGC 4395 is a dwarf galaxy at a distance of about 4.3 Mpc (scale: ∼0.021 pc mas−1). It hosts an intermediate-mass black hole (IMBH) with a mass between ∼104 and ∼105 solar masses. The early radio observations of NGC 4395 with the very long baseline interferometry (VLBI) network, High Sensitivity Array (HSA), at 1.4 GHz in 2005 showed that its nucleus has a sub-mJy outflow-like feature (E) extending over 15 mas. To probe the possibility of the feature E as a continuous jet with a base physically coupled with the accretion disc, we performed deep VLBI observations with the European VLBI Network (EVN) at 5 GHz, and analysed the archival data obtained with the HSA at 1.4 GHz in 2008, NSF's Karl G. Jansky Very Large Array (VLA) at 12–18 GHz and the Atacama Large Millimetre/submillimetre Array (ALMA) at 237 GHz. The feature E displays more diffuse structure in the HSA image of 2008 and has no compact substructure detected in the EVN image. Together with the optically thin steep spectrum and the extremely large angular offset (about 220 mas) from the accurate optical Gaia position, we explain the feature E as nuclear shocks likely formed by the IMBH's episodic ejection or wide-angle outflow. The VLA and ALMA observations find a sub-mJy pc-scale diffuse feature, possibly tracing a thermal free–free emission region near the IMBH. There is no detection of a jet base at the IMBH position in the VLBI maps. The non-detections give an extremely low luminosity of ≤4.7 × 1033 erg s−1 at 5 GHz and indicate no evidence of a disc-jet coupling on sub-pc scales. [ABSTRACT FROM AUTHOR]

X-shaped radio galaxies (XRGs) are those that exhibit two pairs of unaligned radio lobes (main radio lobes and wings). One of the promising models for the peculiar morphology is jet reorientation. To clarify this, we conducted a 5 GHz observation with the European VLBI Network (EVN) of XRG J0725+5835, which resembles the archetypal binary active galactic nuclei (AGNs) 0402+379 in radio morphology, but it is larger in angular size. In our observation, two milliarcsecond-scale radio components with nonthermal radio emission are detected. Each of them coincides with an optical counterpart with similar photometric redshift and (optical and infrared) magnitude, corresponding to dual active nuclei. Furthermore, with the improved Very Large Array (VLA) images, we find a bridge between the two radio cores and a jet bending in the region surrounding the companion galaxy. This further supports the interplay between the main and companion galaxies. In addition, we also report the discovery of an arcsecond-scale jet in the companion. Given the projected separation of ∼100 kpc between the main and companion galaxies, XRG J0725+5835 is likely associated with a dual jetted-AGN system. In both EVN and VLA observations, we find signatures that the jet is changing its direction, which is likely responsible for the X-shaped morphology. For the origin of jet reorientation, several scenarios are discussed. [ABSTRACT FROM AUTHOR]

Caching popular contents at edge networks (such as small-cell base stations) has been proposed to deal with the ever-growing mobile traffic. At the meantime, recommendation system is able to shape user demands for further prompting caching gain. In this paper, we study a multi-antenna multi-cell edge network employing transmit beamforming with caching-aware recommendation and user association. We first establish a framework for the joint problem of beamforming, user association, content caching and recommendation to minimize the content transmission delay of mobile users, by specifying a set of necessary conditions for all four component functions of the network. The resulting optimization problem corresponds to a non-convex, multi-timescale, and mixed-integer programming problem, which is hard to handle. To deal with the difficulty in solving the joint optimization problem by the direct formulation, we equivalently decompose it into three sub-problems. Then, we develop a computationally-efficient iterative algorithm to obtain the sub-optimal solution, where the three subproblems are tackled iteratively. Simulation results are conducted to demonstrate that the proposed algorithm can obtain lower transmission delay than baseline schemes. [ABSTRACT FROM AUTHOR]

Formic acid decomposition (FAD) is one of the most promising routes for rapid hydrogen (H2) production. Extensive efforts have been taken to develop efficient catalysts, which calls for the simultaneous regulation of the electronic structure and particle size of the catalyst. The former factor determines the intrinsic performance, while the latter corresponds to the active site utilization. Here, an effective preparation strategy, pre-nucleation coupled with in situ reduction, is developed to realize and well-tune both surface electronic states and particle size of the pallidum (Pd) catalyst. Benefiting from the structural merits, the as-prepared catalyst exhibits high mass-specific activity of 8.94 molH2/(gPd·h) with few carbon monoxide (CO) molecules, and the activation energy could reach a value as small as 33.1 kJ/mol. The work not only affords a highly competitive FAD catalyst but also paves a new avenue to the synthesis of ultra-fine metal nanoparticles with tailorable electronic structures. [ABSTRACT FROM AUTHOR]

This paper provides an overview of rubber bitumen (RB) modification mechanisms, factors affecting storage stability, and characterization methods. The focus is on summarizing the methods to improve the storage stability of RB. Results indicate that the modification of RB primarily involves swelling and degradation. The settling velocity of crumb rubber (CR) is influenced by the particle size, density, and bitumen viscosity. To evaluate the storage stability of modified bitumen, widely applicable and preferred methods include softening point and rheological property tests. The storage stability of RB can be improved by increasing the swelling rate of CR, promoting crosslinking between CR and bitumen, and reducing CR agglomeration. Commonly used improvement methods include CR selection, the Terminal Blend (TB) curing process, adding modifiers, solubilization blending, the screw extrusion process (SEP), chemical reagent activation, and physical energy activation. The TB curing and SEP are more suitable for engineering-scale applications and yield improved results. However, high production temperatures may compromise the mechanical properties of CR, leading to drawbacks such as high energy consumption and environmental pollution, a problem requiring further exploration. Utilizing bitumen analogs rich in aromatic fractions as solubilizers for CR pretreatment has emerged as an effective option, offering advantages such as simplicity, resource conservation, and favorable improvements. Future research should focus on a deeper investigation of these processes. [Display omitted] • Methods to improve the compatibility of crumb rubber with bitumen are summarized. • Different characterization methods for storage stability are evaluated. • Reducing the crosslink density of rubber improves rubber bitumen storage stability. • Solubilization blending can be considered a sustainable and capable approach. [ABSTRACT FROM AUTHOR]

Image dehazing is an improtant image pre-processing step for many computer vision tasks with many proposed methods using convolutional neural networks. Ordinary Differential Equations (ODE) are a powerful mathematical tool in social and natural science, leading to better understanding, prediction, and use of information systems. Because prior knowledge has demonstrated its effectiveness in many practical domains, we design a Visual Attention Network (VAN) and an ODE-inspired Network (ODEN) based on prior knowledge. Then, we develop a multi-model fuzzy fusion strategy, which integrates results predicted by the prior-based Visual Attention Network (VAN) and the ODE-inspired Network (ODEN) into a single network to leverage their respective strengths in improving the dehazing performance. First, to utilize the haze-related prior for dehazing, the VAN removes haze with the help of the haze attention map. Then, to improve performance of stacked residual blocks inspired by the first-order Euler method in ODE-based methods, the ODEN is built by only 3 Runge–Kutta Modules (RKM), each of which not only is related to the stable fourth-order Runge–Kutta method implemented in the Runge–Kutta Block (RKB), but also combines the RKB with an attention mechanism. Finally, an attention based fusion mechanism is used to fuse results estimated by the ODEN and the VAN based on the multi-level features extracted by a pretrained ResNeXt. The experimental results demonstrate that the proposed method outperforms existing state-of-the-art methods in terms of visual effects and accuracy. The average PSNR and SSIM on three public datasets are 31.36 and 0.9766, respectively, which are better than the compared state-of-the-art methods. [ABSTRACT FROM AUTHOR]

The diffusion bonding of YG8 cemented carbide and 40Cr steel was performed using spark plasma sintering with Ni powder as the interlayer. The influence of bonding temperatures ranging from 700 to 1100 °C on the bonding interface morphology, mechanical properties, and failure mechanism of the joints was studied. By calculating the diffusion coefficients of Ni and Fe and observing the changes in the interface morphology, the pores at the Ni/40Cr interfaces were identified as Kirkendall voids formed because of the unbalanced diffusion of Ni and Fe. The diffusion activation energy of Ni in Fe was 87.37 kJ/mol, and that of Fe in Ni was 58.08 kJ/mol. The use of a pulsed current significantly reduced the diffusion activation energy, making diffusion easier. The bending strength of the joints increased sharply in the range from 700 to 900 °C, subsequently increased slowly, and tended to stabilise in the range from 900 to 1100 °C. The highest bending strength of 1080 MPa was achieved for the joint bonded at 1100 °C, which was attributed to the improved bonding of the YG8/Ni and Ni/40Cr interfaces and the resulting effects of the interlayer plastic constraint. The thickness of the Co Ni diffusion zone at the YG8/Ni interface appeared to form a decisive factor in determining the failure locations of the joints. As the bonding temperature increased, the improved diffusion of Co and Ni enhanced the metallurgical bonding of the YG8/Ni interface, and the fracture position shifted from the polished surface of the YG8 base material (700 °C) to the Ni interlayer (1100 °C). • Effect of bonding temperature on the welding of YG8/40Cr joints is studied. • The welding morphology and failure mechanism of YG8/40Cr joints are investigated. • The bending strength of YG8/40Cr joint in this work reaches up to 1080 MPa. [ABSTRACT FROM AUTHOR]

In order to solve the leakage problem of rotating machinery under the condition of large clearance, a new type of divergent magnetic fluid sealing device with secondary magnetic source was designed. The magnetic field distribution in the clearance of the magnetic fluid seal was simulated by the finite element method of magnetic field, and the theoretical value of the sealing pressure resistance was calculated according to the pressure resistance theory of the divergent magnetic fluid seal. The influences of the volume of magnetic fluid injection, the number of teeth, the clearance, and the eccentricity of the rotating shaft on the pressure resistance abilities of divergent magnetic fluid seal were studied by experimental method and compared with the pressure resistance experimental value of ordinary magnetic fluid seal. The results showed that when the injection volume of magnetic fluid is more than 3 ml, the sealing pressure resistance ability of the magnetic fluid does increase greatly and tends to be stable gradually. The saturated magnetic fluid injection volume of divergent magnetic fluid seal with large clearance is 3 ml. With the increase of radial teeth, the pressure resistance ability of magnetic fluid seal first increases and then decreases. With the increase of axial teeth, the pressure resistance ability of magnetic fluid seal also increases. With the increase of radial clearance, the pressure resistance value of magnetic fluid seal first increases and then decreases. With the increase of axial clearance, the pressure resistance value of magnetic fluid seal decreases. The pressure resistance ability of divergent magnetic fluid seal is significantly higher than that of ordinary magnetic fluid seal. [ABSTRACT FROM AUTHOR]

With the rapid development of new energy sources and the increasing proportion of electric vehicles (EVs) connected to the power grid in China, peak load regulation of power systems will face severe challenges. Therefore, in this study, we analyzed the relationship between the electricity consumption characteristics of EVs and the peak load regulation (PLR) mechanism of power systems, and we proposed an operation mode for virtual power plants with EVs to participate in the auxiliary service market and facilitate deep peak load regulation in the thermal power units. Based on the electricity demand‐side management theory and cost‐benefit analysis method, we constructed a decision model for economic deep peak load regulated operation (DPLR) of the auxiliary thermal power units in a virtual power plant with EVs, aiming to optimize the operation efficiency. The case study showed that a virtual power plant that included EVs can effectively reduce the total PLR cost of the system and the peak valley difference of the net load as well as improve the economic benefits of the thermal power units. The results indicated that the virtual power plant had improved economic efficiency. Therefore, the results of this research can help improve the PLR capacity of the grid and significantly promote the consumption of intermittent renewable energy. [ABSTRACT FROM AUTHOR]

Content caching is recognized as a promising solution to release the heavy burden of backhaul links and decrease the content transmission latency in Fog radio access networks (Fog-RANs). However, the content caching design is still a challenging problem with considering the user request patterns, the content delivery strategies, and the limited caching capacity. Recommendation has the capability of reshaping users’ content requests for further prompting caching gain. The joint recommendation, caching, beamforming holds the potential to improve the system performance of Fog-RANs. In this paper, a joint recommendation, caching, and beamforming scheme is proposed for multi-cell multi-antenna recommendation aware Fog-RANs. Aiming at minimizing the content transmission latency, we formulate a joint recommendation, caching, and beamforming optimization problem. The minimization problem is a very challenging two-timescale mixed integer nonlinear programming problem, which is hard to solve in general. By exploring structural properties of the problem, we propose an alternative optimization algorithm with low complexity through decomposing the original problem into three sub-problems. Extensive simulations show that our proposed method can significantly reduce the content transmission delay. [ABSTRACT FROM AUTHOR]

The energy cost minimization for mission-critical internet-of-things (IoT) in mobile edge computing (MEC) system is investigated in this work. Therein, short data packets are transmitted between the IoT devices and the access points (APs) to reduce transmission latency and prolong the battery life of the IoT devices. The effects of short-packet transmission on the radio resource allocation is explicitly revealed. We mathematically formulate the energy cost minimization problem as a mixed-integer non-linear programming (MINLP) problem, which is difficult to solve in an optimal way. More specifically, the difficulty is essentially derived from the coupling of the binary offloading variables and the resource management among all the IoT devices. For analytical tractability, we decouple the mixed-integer and non-convex optimization problem into two sub-problems, namely, the task offloading decision-making and the resource optimization problems, respectively. It is proved that the resource allocation problem for IoT devices under the fixed offloading strategy is convex. On this basis, an iterative algorithm is designed, whose performance is comparable to the best solution for exhaustive search, and aims to jointly optimize the offloading strategy and resource allocation. Simulation results verify the convergence performance and energy-saving function of the designed joint optimization algorithm. Compared with the extensive baselines under comprehensive parameter settings, the algorithm has better energy-saving effects. [ABSTRACT FROM AUTHOR]

• Traditional two-way coupled Euler-Lagrange(EL) underestimates the drag force and fails in supersonic flow laden finite-size particles. • An upward weighted average method is implemented for E to L coupling to well restore the actual and undisturbed gas-phase quantities acting on particles. • An upward mix-gaussian function is proposed for L to E coupling to reproduce the shock and wake zone of particle in terms of the kernel widths commended. • The modified method not only allows to track arbitrary finite-size particles, but also improves the accuracy of classical PSIC-EL in supersonic flow. In Euler-Lagrange (EL) framework, the Gauss kernel (GK) is usually introduced to avoid Dirac source disturbance of traditional particle-in-cell (PIC) method in subsonic regime. This work investigates the applicability and limitations of PIC-two-way coupling and GK for finite-size particles subjected to supersonic and dilute regime. Results indicate that the source disturbance of GK always peaks at the symmetric center of GK causing a suboptimal shock and ignoring wake in supersonic regime. Meanwhile, classical PIC-interpolation underestimates the drag force on particles due to shock and finite-size effects. To circumvent those issues, a modified coupling method utilizing upstream weighting averaged method and mix-gaussian kernel is proposed to optimize Euler-to-Lagrange coupling and Lagrange-to-Euler coupling, respectively. The modified method not only allows for accurate tracking of arbitrary finite-size particles in supersonic flows but also restores the undisturbed laden flow quantities exerting on particles. Shock and wake zone are reproduced before and after the particle based on recommended parameters. Furthermore, the modified method is validated using a particle-pair exposed to supersonic flow referred from Utkin's experiment(Utkin et al., 2021), and shows excellent agreement. Providing new insight into comprehending for two-way coupled Euler-Lagrange to simulate finite-size particles laden by supersonic flow. Dimensionless pressure and streamwise velocity using different two-way coupling methods [Display omitted] [ABSTRACT FROM AUTHOR]

Radio emission from the high- and super-Eddington accreting active galactic nuclei (AGNs) has various origins: a persistent jet, the magnetized corona, and the wind-like outflows. It is still unclear which is the leading mechanism responsible for the observed radio emission and how the radio emission is related to other characteristic parameters such as the Eddington ratio and black hole mass. In this paper, we present the 5 GHz Very Large Array (VLA) observational results of a sample of 25 extremely high Eddington accreting supermassive black holes (EESBHs, the Eddington ratio λEdd close to or above 1) in narrow-line Seyfert 1 galaxies, among which 22 sources are detected. Most of the EESBHs show a compact radio structure from a few hundred parsecs to 1 kpc scale. We estimated the lowest star formation rate surface density required for producing the observed radio emission and found that it is higher than the largest value previously detected in circumnuclear starburst galaxies, implying that the radio emission is from the AGN activity. Along with a comparison sample, we find an overall inverse –λEdd correlation ranging from sub- to super-Eddington ratios. The high-Eddington and mildly super-Eddington AGNs (−0.5 < log) have a radio-to-X-ray luminosity ratio LR/LX ∼ 10−5–10−4 and a steep radio spectrum, supporting that the radio emission is from transient ejecta (outflows) of corona; however, the jet contribution cannot be entirely ruled out. Our highly super-Eddington sources (log) have a flatter radio spectrum, along with its low radio luminosity: ; their radio emission is likely dominated by a magnetized corona, and a radiation-pressure-caused jet is also proposed in this paper. [ABSTRACT FROM AUTHOR]

The stepped magnetofluid seal is an effective method for improving the pressure ability of ordinary magnetofluid seals (OMS) with large clearance. At present, the research on stepped magnetofluid seal with less than 0.4 mm small clearance has not been carried out yet. The equivalent magnetic circuit design of converging stepped magnetofluid seal (CSMS) with small clearance has been carried out and verified by magnetic field finite element method based on the CSMS theory and magnetic circuit theory. The effects of the width of the axial seal position, the height of the radial seal position, the number of the pole tooth in the axial seal position, and the number of the pole tooth in the radial seal position on the theoretical pressure ability of the CSMS are investigated by numerical simulation. The calculation results are analyzed and discussed. The results show that the magnetic flux leakage at the junction of the permanent magnet and pole piece causes the higher pressure ability of the CSMS structure designed by the equivalent magnetic circuit method than that calculated by the magnetic field finite element method. When the width of the axial seal position is greater than the height of the radial seal position and the number of pole teeth in the axial seal position is less than the number of pole teeth in the radial seal position, the CSMS has the best effect. Compared with OMS with small clearance, CSMS has greater advantages. [ABSTRACT FROM AUTHOR]

Features extraction and analysis for human activity recognition (HAR) have been studied for decades in the 5th generation (5G) and beyond the 5th generation (B5G) era. Nowadays, with the extensive use of unmanned aerial vehicles (UAVs) in the civil field, integrating wireless signal receivers on UAVs could be a better choice to receive hearable signals more conveniently. In recent years, the HAR system based on CSI based on WiFi radar has received widespread attention due to its low cost and privacy protection property. However, in the existing CSI-based HAR system, there are two disadvantages: (1) The detection threshold is manually set, which limits its adaptability and immediacy in different wireless environments. (2) A sole classifier is used to complete the recognition, resulting in poor robustness and relatively low recognition accuracy. In this paper, we propose a CSI-based device-free HAR (CDHAR) system with WiFi-sensing radar integrated on UAVs to recognize everyday human activities. Firstly, by using machine learning, CDHAR applies kernel density estimation (KDE) to obtain adaptive detection thresholds to complete the extraction of activity duration. Second, we proposed a random subspace classifier ensemble method for classification, which applies the frequency domain feature instead of the time domain feature, and we choose each kind of feature in the same amount. Finally, we prototype CDHAR on commercial WiFi devices and evaluate its performance in both indoor environment and outdoor environments. The experiment results tell that even if experimental scenario varies, the accuracy of activity durations extraction can reach 98% and 99.60% whether in outdoor or indoor environments. According to the extracted data, the recognition accuracy in outdoor and indoor environments can reach 91.2% and 90.2%, respectively. CDHAR ensures high recognition accuracy while improving the adaptability and instantaneity. [ABSTRACT FROM AUTHOR]

To satisfy the demand for thrust control on solid rocket motors and solid ramjet engines, numerical simulation of the effect of high-voltage electric fields on the combustion characteristics of polymethyl methacrylate (PMMA) under lateral inflow was undertaken. The mechanism of the effect of electric fields on the regression rate and mass flow rate of PMMA was analyzed. The results show that PMMA mass flow rate can increase by about 54% when subjected to positive voltages. The PMMA mass flow rate can not only increase by about 5.5% but also decrease by about 14% under the action of negative voltages. When the oxygen mass fraction is 54.5% at 0.101 MPa, the effect of electric fields on PMMA mass flow is weakened as the lateral velocity increases. When the inflow velocity is 1.95 m s−1 and oxygen mass fraction is 23.2%, the effect of electric fields on PMMA mass flow is decreased as the pressure rises. The effect of electric fields on PMMA regression rate is mainly due to the electric-field-induced volumetric body force. It will result in large-scale bulk flow movement, known as ionic wind, which changes the distribution of species and affects the heat of reaction, thus causing the changes in flame temperature, finally altering the thermal feedback to the solid phase. • Electric fields can change PMMA regression rate and mass flow rate. • The change of PMMA mass flow rate was closely related to applied voltages. • The change of the regression rate was due to electric body force. [ABSTRACT FROM AUTHOR]

Due to great demands on solid rocket motors and solid ramjets for thrust control, a study of the effect of high-voltage electric fields on the regression rate of polymethyl methacrylate (PMMA) has been undertaken. The flame shape was recorded by a CMOS camera. The regression rate of PMMA was measured. A numerical model of fluid-solid coupling, which is based on experiment and considers physico-chemical phenomena associated with the flame-field interaction process, has been developed to explain experimental observations. In order to reduce the computational workload, the radiation loss, including the soot radiation is not considered in the numerical simulation. The mechanism of the effect of electric fields on the regression rate of PMMA is analysed. The numerical simulation shows that the change of the regression rate of a PMMA tip under the action of electric fields is consistent with experimental results. Studies show that electric fields can change the regression rate of PMMA, increasing it by about 38%. The regression rate on the burning surface is increased when subjected to positive electric fields. Under a negative electric field, part of the burning surface is subjected to an increased regression rate, and some thereof is subjected to a decreased regression rate. The effect of electric fields on the regression rate of PMMA is mainly due to the interaction of buoyancy and the electric field induced volumetric body forces. • Electric fields can change the regression rate of PMMA. • The change of the regression rate was closely related to applied voltage. • The change of the regression rate was due to the action of buoyancy and"ionic wind". [ABSTRACT FROM AUTHOR]

In this paper, we investigate a hybrid mobile cloud/edge computing system with coexistence of centralized cloud and mobile edge computing, which enables computation offloading and data caching to improve the performance of users. Computation offloading and data caching decisions are jointly optimized to minimize the total execution delay at the mobile user side, while satisfying the constrains in terms of the maximum tolerable energy consumption of each user, the computation capability of each MEC server, and the cache capacity of each access point (AP). The formulated problem is non-convex and challenging because of the highly coupled decision variables. To address such an untractable problem, we first transform the original problem into an equivalent convex one by McCormick envelopes and introducing auxiliary variables. To the end, we propose a distributed algorithm based on the alternating direction method of multipliers (ADMM), which can achieve near optimal computation offloading and data caching decisions. The proposed algorithm has lower computational complexity compared to the centralized algorithm. Simulation results are presented to verify that the proposed algorithm can effectively reduce computing delay for end users while ensuring the performance of each user. [ABSTRACT FROM AUTHOR]

Two series of Pt(II) polyynes bearing fluorene-type ligands with ethynyl units at different positions have been synthesized. In the absorption spectra, the Pt(II) polyynes bearing fluorene-type ligands with ethynyl units at 3,6-position have blue-shift with respect to the corresponding analogs bearing fluorene-type ligands with ethynyl units at 2,7-position, showing better transparency in the visible light region. Moreover, the Pt(II) polyynes bearing fluorene-type ligands with ethynyl units at 3,6-position show stronger triplet emission than corresponding analogs bearing fluorene-type ligands with ethynyl units at 2,7-position in the photoluminescent (PL) spectra. Furthermore, these Pt(II) polyynes were applied to optical power limiting (OPL) field. The Pt(II) polyynes bearing fluorene-type ligands with ethynyl units at 2,7-position show better OPL performance than the corresponding analogs with fluorene-type ligands of ethynyl units at 3,6-position. Therefore, changing the position of the ethynyl units in fluorene-type ligands can not only effectively control the photophysical properties of the Pt(II) polyynes, but also has an important effect on their OPL ability. By changing the substitution positions of two ethynyl units in the fluorene-type ligands, the photophysical properties and optical power limiting performance of these Pt(II) polyynes can be effectively tuned. Image 1 • Two series of Pt(II) polyynes bearing fluorene-type ligands with ethynyl units at different positions. • Enhanced transparency and triplet emission of Pt(II) polyynes with fluorene-type ligands with ethynyl units at 3,6-position. • Better OPL performance of the Pt(II) polyynes bearing fluorene-type ligands with ethynyl units at 2,7-position. [ABSTRACT FROM AUTHOR]

Superhydrophobic surfaces patterned with hydrophilic groove structures have promising applications in microfluidics. In this work, hydrophilic groove patterns with stable wettability were created directly on superhydrophobic Al surface by micromilling. Feasibility of applying diverse milled hydrophilic patterns, including dimples, ring grooves and reservoirs connected by winding channels in a variety of droplet manipulations, such as water/oil/air storage, water transport, etc. was tried out. Experimental results showed that the milled dimples and ring grooves on the superhydrophobic background can function as a multifunctional platform for storing micro-liter sized water, oil and gas bubbles; two milled reservoirs connected by a milled channel can serve as a open surface microfluidics to transport liquid using Laplace pressure difference. On the basis of the liquid transport between two reservoirs, more sophisticated liquid handling such as droplet separation and mixing were achieved by transporting liquid among multiple reservoirs. It is thus clear that the micromilling is a quite suitable approach to create complex hydrophilic groove structures on superhydrophobic background for applications to diverse interface-driven microfluidics. [ABSTRACT FROM AUTHOR]

To improve the pressure capability of ordinary ferrofluid seals with a large gap, a novel type of converging stepped ferrofluid seals was proposed. The leakage positions and the magnetic field distributions in the sealing gaps of the new device are studied computationally by means of the finite-element method. The theoretical pressure capabilities of the seal are calculated based on a new expression introduced for the particular new seal geometry and for different sealing gaps. Computational results for effects of the radial and axial sealing gaps on the pressure capabilities of the seal are compared to the experimental results obtained from measurements employing a prototype of the proposed new seal. A good agreement between theoretical and experimental results is obtained. It is found that the pressure capabilities of the new seal depend on the height of the radial sealing gap and on the width of the axial sealing gap. [ABSTRACT FROM AUTHOR]

Background: The aim of the present study was to examine the risk factors for developing diabetes after 3 years in an elderly Chinese suburban population with impaired fasting glucose (IFG). Methods: The study population comprised residents of the Hangu area of Tianjin, China, with IFG, aged ≥60 years, who joined the national free physical examination program (n = 328; mean [±SD] age 68.0 ±6.1 years; 48.2% men). Diabetes was defined by self‐report of a physician's diagnosis or fasting plasma glucose (FPG) ≥7.0 mmol/L; IFG was defined as FPG ≥5.6 and < 7.0 mmol/L. Risk factors of incident diabetes at the 3‐year follow‐up were analyzed individually using logistic regression analysis. Results: Between baseline and the 3‐year follow‐up, 56 subjects with IFG at baseline had developed diabetes. After multivariate adjustment for demographic and clinical factors, the incidence of diabetes increased with higher FPG (odds ratio [OR] 9.30, 95% confidence interval [CI] 2.84–30.48), but decreased with the grip strength/weight ratio (OR 0.88, 95% CI 0.82–0.94). Moreover, the combination of higher FPG and lower grip strength/weight was associated with a higher incidence of diabetes than higher FPG only or lower grip strength/weight (P < 0.05). Conclusion: The present study indicates that higher FPG and lower muscle strength are associated with glycemic deterioration among subjects with IFG after 3 years. The results suggest that not only glucose levels, but also physical performance may be useful markers of the risk of diabetes in this population. HighlightsThis study showed that glucose levels and physical performance may be useful markers of risk in community‐dwelling elderly with impaired fasting glucose (IFG).This indicates that a better understanding of the factors potentially responsible for the increase in type 2 diabetes mellitus can help policy makers make decisions about diabetes prevention programs and policies. [ABSTRACT FROM AUTHOR]

This study was performed to determine the distribution and chemical fractions of five heavy metals (Cd, Cr, Cu, Pb, and Zn) in sediment from three sampling areas in Swan Lagoon, and their relation to the physiochemical properties of sediment were explored. The results revealed that Cd in sediment from the sand part (SP), muddy sand part (MSP) and sand muddy part (SMP) were potentially highly susceptible and bioavailable since the exchangeable fractions were 21.0%, 27.4%, and 32.1%, respectively, of the total concentrations. A portion of Pb and Zn were observed as reducible fractions owing to their affinity to Fe-Mn; they were able to complex with Fe-Mn oxides and oxyhydroxides in the sediment. A large amount of Cu in the oxidizable fraction may be due to the fact that Cu can easily form stable complexes with organic matter. Cr was overwhelmingly found in the residual fraction, suggesting that Cr was strongly bound in mineral lattices. Enrichment factors (EF) indicated that Cd in three sampling areas suffered severe enrichment, whereas other metals were present in only minor amounts. In addition, Cd may pose a medium to high risk in the MSP and SMP based on risk assessment codes. According to the mean probable effects level quotient, the samples from the MSP and SMP had a 21% probability of toxicity. The multivariate statistical analysis suggested that sediment texture (d0.5, sand and silt), Fe-Mn, and the total organic carbon (TOC) influenced the distribution of the studied metals and their chemical fractions. [ABSTRACT FROM AUTHOR]

It has been an active research issue for many years to construct new bent functions. For k odd with \gcd (n, k)=1 and a\in \mathbb F3^{n}^{*} , the function f(x)=Tr1^{n}(ax^{(({3^{k}+1})/{2})}) is weakly regular bent over \mathbb F3^{n} , where Tr1^{n}(\cdot) is the trace function from \mathbb F3^{n} to \mathbb F3 . This is the well-known Coulter–Matthews bent function. In this paper, we determine the dual function of f(x) completely. As a consequence, we find many classes of ternary bent functions not reported in the literature previously. Such bent functions are not quadratic if k>1 and have (((1+\sqrt 5)/2)^w+1-((1-\sqrt 5)/2)^w+1)/\sqrt 5 or (((1+\sqrt 5)/2)^n-w+1-((1-\sqrt 5)/2)^n-w+1)/\sqrt 5 trace terms, where 0

Abstract: Organic light‐emitting diodes (OLEDs) are one of the most promising technologies for future displays and lighting. Compared with the blue and green OLEDs that have achieved very high efficiencies by using phosphorescent Ir(III) complexes, the red OLEDs still show relatively low efficiencies because of the lack of high‐performance red‐emitting Ir(III) complexes. Here, three highly efficient asymmetric red‐emitting Ir(III) complexes with two different cyclometalating ligands made by incorporating only one electron‐deficient triarylboron group into the nitrogen heterocyclic ring are reported. These complexes show enhanced photoluminescence quantum yields up to 0.96 and improved electron transporting capacity. In addition, the asymmetric structure can help to improve the solubility of Ir(III) complexes, which is crucial for fabricating OLEDs using the solution method. The photoluminescent and oxidation–reduction properties of these Ir(III) complexes are investigated both experimentally and theoretically. Most importantly, a solution‐processed red OLED achieves extremely high external quantum efficiency, current efficiency, and power efficiency with values of 28.5%, 54.4 cd A−1, and 50.1 lm W−1, respectively, with very low efficiency roll‐off. Additionally, the related device has a significantly extended operating lifetime compared with the reference device. These results demonstrate that the asymmetric diarylboron‐based Ir(III) complexes have great potential for fabricating high‐performance red OLEDs. [ABSTRACT FROM AUTHOR]

Polycyclic aromatic hydrocarbons (PAHs) are associated with adverse health effects in humans, and the photocatalysis degradation is regarded as promising technology to remove contaminants from environment. Although many TiO 2 -based photocatalysts were reported to be active for this process, the efficiency is still quite low. In this work, graphene oxide (GO) enwrapped silver phosphate composites were found to exhibit superior activities in the photocatalytic degradation process of a variety of PAHs (naphthalene, phenanthrene and pyrene) under visible light irradiation. The optimum amount of GO was 3.0 wt%. Within several minutes or even seconds’ visible light irradiation, naphthalene, phenanthrene and pyrene can be completely oxidized. Meanwhile, good photocatalytic activity was retained after six cycles run. The trapping experiments gave evidence that degradation was mediated by photogenerated holes, superoxide radicals and hydroxyl radical, different from others OH was found to play a role in the process of pyrene photoreaction. Gas chromatography-mass spectrometer (GC-MS) technique was employed to analyze photodegradation intermediates. Based on the identified intermediates, the plausible photooxidation pathways of PAHs over the surface of GO/Ag 3 PO 4 were proposed. Ultimately, a possible synergetic mechanism associated with Ag surface plasmon resonance effect of GO/Ag 3 PO 4 composite for PAHs photodegradation was suggested. The superior photocatalytic system for the removal of PAHs was presented and simultaneously it shed light on photodegradation of PAHs from a practical point of view. [ABSTRACT FROM AUTHOR]

Seagrass systems are in decline, mainly due to anthropogenic pressures and ongoing climate change. Implementing seagrass protection and restoration measures requires accurate assessment of suitable habitats. Commonly, such assessments have been performed using single-algorithm habitat suitability models, nearly always based on low environmental resolution information and short-term species data series. Here we address eelgrass (Zoostera marina) meadows' large-scale decline (>80%) in Shandong province (Yellow Sea, China) by developing an ensemble habitat model (EHM) to inform eelgrass conservation and restoration strategies in the Swan Lake (SL). For this, we applied a weighted EHM derived from ten single-algorithm models including profile, regression, classification, and machine learning methods to generate a high-resolution habitat suitability map. The EHM was constructed based on the predictive performances of each model, by combining a series of present-absent eelgrass datasets from recent years coupled with oceanographic and sediment data. The model was cross-validated with independent historical datasets, and a final habitat suitability map for conservation and restoration was generated. Our EHM scheme outperformed all single models in terms of habitat suitability, scoring ∼0.95 for both true statistic skill (TSS) and area under the curve (AUC) performance criteria. Machine learning methods outperformed profile, regression and classification methods. Regarding model explanatory variables, overall, topographic characteristics such as depth (DEP) and seafloor slope (SSL) are the most significant factors determining the distribution of eelgrass. The EHM predicted that the overlapping area was almost 90% of the current eelgrass habitat. Using results from our EHM, a LOESS regression model for the relationship of the habitat suitability to both the biomass and density of Z. marina outperformed better than the classic Ordinary Least Squares regression model. The EHM is a promising tool for supporting eelgrass protection and restoration areas in temperate lagoons as data availability improves. [Display omitted] • An ensemble model with high-resolution scale for eelgrass conservation targets. • Classic and non-parametric techniques model relation of HSI and eelgrass density. • The predictive model was constructed and cross-validated with long-term datasets. • Approach can be extended and applied to other costal restoration projects. [ABSTRACT FROM AUTHOR]

The photocatalytic performance of the g-C 3 N 4 photocatalyst was restricted by the low efficiency because of the fast charge recombination. The present work constructed a “killing two birds with one stone” composite (C 16 H 33 (CH 3 ) 3 N) 4 W 10 O 32 /g-C 3 N 4 heterostructured photocatalysts with the aim to greatly promote the charge separation and recycle decatungstate in aqueous solution. Decatungstate was immobilized on g-C 3 N 4 in the form of modified decatungstate (C 16 H 33 (CH 3 ) 3 N) 4 W 10 O 32 via surface bonding method for the first time. Furthermore, a novel ternary (C 16 H 33 (CH 3 ) 3 N) 4 W 10 O 32 /g-C 3 N 4 /rGO photocatalyst was successfully constructed by integrating graphene into the binary (C 16 H 33 (CH 3 ) 3 N) 4 W 10 O 32 /g-C 3 N 4 composite as the electron mediator. The photocatalysts were characterized by XRD, FTIR, FESEM, TEM, UV-vis DRS, PL and EIS measurement. The photocatalytic properties were evaluated in photodecomposition of aqueous methyl orange and phenol under visible-light irradiations. It has been shown that the obtained (C 16 H 33 (CH 3 ) 3 N) 4 W 10 O 32 /g-C 3 N 4 photocatalyst exhibited improved photocatalytic activity and enhanced reduced charge recombination as compared with those of g-C 3 N 4 and (C 16 H 33 (CH 3 ) 3 N) 4 W 10 O 32 . It has been found that the introduction of graphene revealed a synergistic effect between the (C 16 H 33 (CH 3 ) 3 N) 4 W 10 O 32 species, g-C 3 N 4 and graphene existed in the ternary photocatalyst. Consequently, the photocatalytic activity of the ternary (C 16 H 33 (CH 3 ) 3 N) 4 W 10 O 32 /g-C 3 N 4 /rGO photocatalyst was superior to that of the binary one, originating from its stronger visible-light absorption and more reduced charge combination. Finally, recycling experiments revealed that the ternary composite photocatalyst was not only highly efficient but also robust, because it can be used six times without loss of activity, which efficiently solved the problem of recycling decatungstate in reaction system. This work demonstrated that rational design and construction of g-C 3 N 4 -decatungstate composites could open up a new avenue for the development of new efficient visible-light photocatalysts for water disinfection. [ABSTRACT FROM AUTHOR]

[Display omitted] • Near-ultraviolet fluorescence with atypical planar structures. • Atypical planar structure can promote the emission blue-shift. • The enhancing rigidity of molecule can obtain high PLQY. • TPhPO moiety can reduce the LUMO energy level to bring near-ultraviolet emission. • Doped device of DPhPO-Ad achieved the highest maximum η ext of 4.58%. In this work, three D-A-locked near-ultraviolet (NUV) emitters (DPhPO-Oz , DPhPO-Ad and DPhPO-Tz) with atypical planar structures were synthesized by an intramolecular-locked of donor and acceptor (D and A) units. They adopt triphenylphosphine oxide (TPhPO) moiety as accepter, which can improve the electron injection and transportation, reduce the LUMO energy level to widen the bandgap and limit the emission red-shift. By locking the D and A units got D-A-locked emitters with atypical planar structure. This atypical planar structure can increase molecular rigidity and reduce the non-radiative decay of the D-A-locked emitters. It also can increase the PLQY and decrease the intermolecular π–π stacking. The highest PLQY of the D-A-locked emitters is 0.64. Due to their atypical planar structure, all of the three emitters show blue-shifted emission and narrower FHWM with the Commission Internationale de L'Eclairage (CIE y) ≤ 0.03 in toluene solution. In order to further investigate the effect of the atypical planar configurations of the molecules on their emissions. Three additional d -locked emitters (TPhPO-Oz , TPhPO-Ad and TPhPO-Tz) with distinct D-A structures were synthesized. Although the d -locked emitters can also show near-ultraviolet emission with narrow FHWM in toluene, they still exhibit red-shift and wider FHWM in their emission spectra with respect to the D-A-locked emitters. These results indicate that the shorter emission wavelength in the D-A-locked emitters with narrow FHWM should be due to their atypical planar structure. As the above consequence, the NUV organic light-emitting diodes based on DPhPO-Ad can achieve forward-viewing maximum external quantum efficiency (η ext) of 4.58 % with electroluminescence (EL) at 404 nm, CIE y coordinate at 0.05 and narrow FHWM (54 nm). [ABSTRACT FROM AUTHOR]

[Display omitted] • Numerical and experimental studies on multi-stage Tesla valve (MSTV) flow field. • Changes in the flow directions can affect the characteristics of MSTV flow field. • An inlet commutation strategy based on Tesla valve flow field is proposed. • Net power is enhanced over the entire current density range. The net power of a proton exchange membrane fuel cell (PEMFC) is affected by both output power and parasitic power. A Tesla valve flow field is designed to improve the net power of PEMFC. As a valve with no-moving-part, Tesla valve allows the forward and reverse flow of fluid, and a change in the flow direction can greatly affect the characteristics of the valve. In this research, the transport characteristics and output performance of reverse and forward flow for multi-stage Tesla valve (MSTV) flow field in PEMFC are numerically simulated and experimentally studied. The results indicate that the forward and reverse flow of the MSTV flow field show significantly different characteristics in terms of velocity distribution, pressure distribution and oxygen mass fraction. Meanwhile, the pressure drop of the MSTV flow fields is one to two orders of magnitude lower compared to the conventional serpentine flow field (CSFF). Compared with the conventional parallel flow field (CPFF), the peak net power of MSTV flow field for reverse and forward flow can be increased by 19.89% and 3.90%; compared with CSFF, the peak net power of MSTV flow field for reverse flow can be increased by 12.19%. Furthermore, considering parasitic power generated by pressure drop, an inlet commutation strategy based on MSTV flow field has been proposed to enhance the net power of PEMFC under all working conditions. [ABSTRACT FROM AUTHOR]

Mobile cloud computing, which integrates the cloud computing techniques into the mobile environment, is regarded as one of the enabler technologies for 5G mobile wireless networks. There are many sporadic spare resources distributed within various devices in the networks, which can be used to support mobile cloud applications. However, these devices, with only a few spare resources, cannot support some resource-intensive mobile applications alone. If some of them cooperate with each other and share their resources, then they can support many applications. In this paper, we propose a resource cooperative provision mode referred to as "Crowd-funding", which is designed to aggregate the distributed devices together as the resource provider of mobile applications. Moreover, to facilitate high-efficiency resource management via dynamic resource allocation, different resource providers should be selected to form a stable resource coalition for different requirements. Thus, considering different requirements, we propose two different resource aggregation models for coalition formation. Finally, we may allocate the revenues based on their attributions according to the concept of the "Shapley value" to enable a more impartial revenue share among the cooperators. It is shown that a dynamic and flexible resource-management method can be developed based on the proposed Crowd-funding model, relying on the spare resources in the network. [ABSTRACT FROM AUTHOR]

Vector linear network coding (LNC) is a generalization of the conventional scalar LNC, such that the data unit transmitted on every edge is an L -dimensional vector of data symbols over a base field GF( q ). Vector LNC enriches the choices of coding operations at intermediate nodes, and there is a popular conjecture on the benefit of vector LNC over scalar LNC in terms of alphabet size of data units: there exist (single-source) multicast networks that are vector linearly solvable of dimension L over GF( q . This paper introduces a systematic way to construct such multicast networks, and subsequently establish explicit instances to affirm the positive answer of this conjecture for infinitely many alphabet sizes p^{L} with respect to an arbitrary prime p$ . On the other hand, this paper also presents explicit instances with the special property that they do not have a vector linear solution of dimension L$ over GF(2) but have scalar linear solutions over GF( q'$ ) for some , where $q'$ can be odd or even. This discovery also unveils that over a given base field, a multicast network that has a vector linear solution of dimension $L$ does not necessarily have a vector linear solution of dimension $L' > L$ . [ABSTRACT FROM AUTHOR]

A highly efficient visible-light-driven acidified g-C 3 N 4 (ACNS)/g-C 3 N 4 isotype heterojunction photocatalysts were synthesized by ultrasonic dispersion assisted electrostatic self-assembly strategy for the first time. The photocatalytic oxidation ability of the novel photocatalysts were evaluated using methyl orange (MO) as a target pollutant. The obtained ACNS/g-C 3 N 4 photocatalysts were characterized by X-ray powder diffraction (XRD), Fourier transform infrared spectrometry (FTIR), UV–vis diffuse reflection spectroscopy (DRS), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) methods. The photocatalysts exhibited a significantly enhanced photocatalytic performance in degrading MO under visible light illumination (λ > 420 nm) compared with the pristine ACNS and g-C 3 N 4 solely. The optimal ACNS content for the photocatalytic activity of the heterostructured composites was determined. The 30 wt.% ACNS/g-C 3 N 4 exhibited the highest photocatalytic activity, which showed a reaction rate constant as high as 0.0216 min −1 , 4.3 times higher than that of bare g-C 3 N 4 . The mechanism of the photocatalysts was investigated by determination of reactive species in the photocatalytic reactions and photoluminescence technique. The quenching effects of different scavengers displayed that the reactive h + and O 2 − played major role in the reaction systems. The synergic effect between the ACNS and g-C 3 N 4 was found to lead to an improved photo-generated carrier separation and hence the photocatalytic activities of the composite photocatalysts were increased significantly. [ABSTRACT FROM AUTHOR]

• An abnormal in-plane thermal conductivity anisotropy of bilayer α-phase tellurene is found. • κ⊥ / κ∥ of 2L-aTe is 1.174, in sharp contrast to bulk Te for which κ// / κ⊥ is 0.435. • Phonon transport properties and lattice structure change are analyzed to explain the anomalous thermal conductivity anisotropy. • Covalent-like quasi-bonding and its electronic origins are discussed to uncover the physical mechanism. In layered materials, it is well known that the cross-plane or cross-chain (CC) thermal conductivity is lower than that of the in-plane or along-chain direction due to weaker bonding in the cross-plane or CC directions. In this work, surprisingly, we predict using first-principles that the CC thermal conductivity κ ⊥ is higher than the along-chain thermal conductivity κ ∥ with a κ ⊥ / κ ∥ ratio of 1.174 in bilayer α -phase tellurene (2L-αTe), an emerging 2D material that has recently drawn extensive interest due to its intriguing electronic, thermoelectronic, and piezoelectronic properties. Also, the room-temperature κ ⊥ and κ ∥ of 2L-αTe are 5.69 W/mK and 4.85 W/mK, which are 251% and 31% enhanced from that of bulk Te, respectively. A detailed analysis of lattice structure, phonon spectra, and electron properties of 2L-αTe and bulk Te is provided. We find that the larger lattice shrink in CC direction and the change in band angle lead to stiffened phonons and weaker anharmonicity, which in turn yield higher phonon group velocity and longer phonon lifetime in CC direction for 2L-αTe, resulting in the enhanced thermal conductivity and the anomolus thermal anisotropy. Crystal orbital Hamiltan population (COHP) and electron localization function (ELF) analysis demonstrate the enhancement of the strength of "covalent-like quasi-bonding" (CLQB) in CC direction of 2L-αTe, which is accompanied by the lattice shrink in CC direction and the change of band angle. Our study identifies a case of unexpected anisotropic thermal transport in 2D materials, and sheds light on the improvement of thermal conductivity isotropy in 2D materials for the thermal management of electronic devices. [ABSTRACT FROM AUTHOR]

It has been claimed in the theoretical linguistic literature ( Pan, 1997; Huang et al., 2009 ) that (i) the Chinese reflexive ziji ‘self’, if occurring more than once in a single clause, can take separate antecedents, and (ii) a third-person NP can block the long-distance binding of ziji . On the basis of corpus data, this paper investigates the claim, demonstrating that it is neither empirically possible nor cognitively plausible for multiple ziji s in a single clause to have distinct referents, and the so-called blocking effect induced by a third-person NP is unlikely to exist. It is shown that the perspective center is determined relative to the communicative context, which in turn determines the linear order of sentence structure containing multiple ziji s. Precisely, the first ziji 's reference determines the rest of ziji s’ reference(s). [ABSTRACT FROM AUTHOR]

The rapid and controllable sliding of droplets on anisotropic slippery liquid infused porous surfaces (SLIPS) has promising application prospects in the fields of energy, lab-on-a-chip, etc. In this work, the fabrication of hydrophilic patterned SLIPS on copper substrates that can achieve efficient droplet transport and fog harvest was reported. A single superhydrophilic stripe and array of superhydrophilic stripes were fabricated on SLIPS background, respectively. Contact angles, sliding angles and contact angle hysteresis of the surfaces were investigated and analyzed. Results showed that hydrophilic patterned SLIPS with superhydrophilic stripe array had remarkable anisotropy in contact angle hysteresis in the parallel and perpendicular directions due to the large energy barrier induced by liquid surface tension in the direction perpendicular to the stripes, which can be used to transport droplets rapidly and precisely. In addition, the fog harvest performance, as a typical example of droplet transport, was significantly improved on hydrophilic patterned SLIPS due to high nucleation density on the hydrophilic SLIPS, high condensate mobility, efficient condensate transferring from SLIPS to superhydrophilic stripes and liquid shedding along the stripes for departing. [Display omitted] • Hydrophilic patterns were fabricated on hydrophobic surfaces by laser processing. • This laser processing method is suitable for many substrates. • Hydrophilic patterned slippery surfaces showed excellent droplet anisotropy. • Hydrophilic patterned slippery surfaces showed excellent fog harvest performance. [ABSTRACT FROM AUTHOR]

Asphalt pavements are widely used in road engineering owing to their good skid resistance, ease of maintenance, and high driving comfort. However, large amounts of toxic fumes are produced during petroleum asphalt heating, asphalt mixture preparation, and pavement construction. This review clarifies the fuming mechanisms and hazards of asphalt fumes with the aim of promoting the application of fume-suppression asphalt(s) and reducing the emission levels of asphalt fumes. First, starting from the fuming mechanisms of hot asphalt, the composition and hazards of asphalt fumes are described. Second, existing indoor and on-site asphalt fume testing methods are discussed. Finally, the inhibitory effects and mechanisms of different types of fume suppressants are discussed separately to provide a reference for the popularization and application of fume-suppression asphalt. The review shows that the existing descriptions of the fume-generation mechanisms are based on physical phenomena, and there is a lack of systematic research at the chemical level. An indoor asphalt fume test is usually conducted using a fume-generation and collection device, where the main test object is an asphalt binder. Therefore, it is difficult to simulate real fuming conditions in these tests. A field testing mainly evaluates the concentrations of different types of asphalt fumes, and there is a lack of standardization of asphalt fume test methods and emission specifications. Existing asphalt fume suppressants mainly include polymers, flame retardants, warm mixing agents, adsorbents, and nanomaterials; traditional fume suppressants such as polymers, flame retardants, and warm mix agents have poor fume-suppression effects or reduce the pavement performance. Meanwhile, nanomaterial-based fume suppressants have good fume-suppression and improved pavement performance to some extent; however, they are still in the early stages of exploration. Therefore, future research should focus on asphalt fume-generation mechanisms, asphalt fume-evaluation methods and specifications, and environmentally friendly nanomaterial-based fume suppressants. [Display omitted] • The asphalt fuming mechanism in different construction stages were summarized. • The test methods of asphalt fume were discussed in detail from the perspective of indoor test and field test. • The inhibitory effect, mechanism and working performance of different fume suppressants were classified and summarized. [ABSTRACT FROM AUTHOR]

Because a greater proportion of large-scale electric vehicles (EVs) are connected to the grid, their stochastic charging load has a significant impact on the power quality and economic operation of the distribution network. However, a random charging load can be transformed into flexible demand response resources through intelligent control of the EV charging process. Therefore, a bi-level optimization model for EV charging is proposed in this study based on the real-time charging price according to the regional grid load, providing more flexible charging strategies for EVs. First, the framework for a bi-level optimization control strategy for EV charging based on the load is developed. Based on the regional grid load, the charging price of each period is optimized in accordance with the load elasticity coefficient of the real-time charging price. Second, an upper-level EV charging price optimization model and a lower-level EV charging load optimization model are established. Third, an optimal control strategy for the scheduling of EV charging is developed, which considers the charging cost of EV users as the objective function and the standard deviation and peak-valley difference of the regional grid load as validation functions. Finally, using a regional power grid in China as the simulation object, the daily operation data of the grid are used to analyze and verify the proposed model. The simulation results demonstrate that the optimized real-time charging price can better respond to the regional grid load, smooth the regional grid load curve, reduce the peak-valley difference, promote clean energy consumption, and further lower the charging cost for EV users. • A framework of the bi-level optimization for electric vehicle charging is proposed. • Load elasticity coefficient of real-time charging price is introduced. • Real-time charging price model following the load of the power grid is constructed. • Impacts of real-time charging price change on electric vehicle load are analyzed. • Flexible charging strategies are provided for electric vehicle users. [ABSTRACT FROM AUTHOR]

Herein, combining photocatalysis and Fenton oxidation, a photo-assisted Fenton system was conducted using Fe-doped Bi4O5Br2 as a highly efficient photocatalyst to realize the complete degradation of Tetracycline antibiotics under visible light. It has been observed that the optimized photocatalyst 5%Fe-doped Bi4O5Br2 exhibits a degradation efficiency of 100% for Tetracycline with H2O2 after 3 h visible-light irradiation, while a degradation percentage of 59.8% over the same photocatalyst and 46.6% over pure Bi4O5Br2 were obtained without the addition of H2O2 (non-Fenton process). It is unambiguous that a boost photo-assisted Fenton system for the degradation of Tetracycline has been established. Based on structural analysis, it demonstrated that the Fe atoms in place of the Bi sites may result in the distortion of the local structure, which induced the occurrence of the spontaneous polarization and thus enhanced the built-in electric field. The charge separation efficiency is enhanced, and the recombination of electrons and holes is inhabited so that more charges are generated to reach the surface of the photocatalyst and therefore improve the photocatalytic degradation efficiency. Moreover, more Fe (II) sites formed on the 5%Fe-Bi4O5Br2 photocatalyst and facilitated the activation of H2O2 to form oxidative species, which greatly enhanced the degradation efficiency of Tetracycline. [ABSTRACT FROM AUTHOR]