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Featured Application: Resource and environmental effects. Accretionary wedge earthquakes usually occur in the overriding crust close to the trench or above the cold nose of the mantle wedge. However, the mechanism and temperature properties related to the slab dip angle remain poorly understood. Based on 3D thermal models to estimate the subduction wedge plate temperature and structure, we investigate the distribution of wedge earthquakes in Alaska, which has a varying slab dip angle along the trench. The horizontal distance of wedge-earthquake hypocenters significantly increases from the Aleutian Islands to south–central Alaska due to a transition from steep subduction to flat subduction. Slab dehydration inside the subducted Pacific plate indicates a simultaneous change in the distances between the intraslab metamorphic fronts and the Alaskan Trench at various depths, which is associated with the flattening of the Pacific plate eastward along the strike. The across-arc width of the wedge-earthquake source zone is consistent with the across-arc width of the surface high topography above the fully dehydrated megathrust, and the fluid upwelling spontaneously influences wedge seismotectonics and orogenesis. [ABSTRACT FROM AUTHOR]

In recent years, with the rapid development of sensing technology and the Internet of Things (IoT), sensors play increasingly important roles in traffic control, medical monitoring, industrial production and etc. They generated high volume of data in a streaming way that often need to be processed in real time. Therefore, streaming data computing technology plays an indispensable role in the real-time processing of sensor data in high throughput but low latency. However, there are two problems in deploying streaming data process ability in cloud computing data centre. Firstly, massive sensor nodes simultaneously upload data to the remote cloud computing data centre, which requires a large number of bandwidth resources supports. The existing network infrastructure cannot provide enough bandwidth at a reasonable price. Secondly, due to the geographical distribution characteristics of the cloud computing data centre, there will inevitably be large transmission delay during the process of data transmission. Such end-to-end delay is intolerable to mobile applications especially for those latency sensitive tasks. In view of the above problems, this paper proposes an autonomous driving oriented edge streaming data processing framework, which migrates the computing and storage capability from the remote cloud data centre to the edge data centre. It focuses on the change of vehicle flow in a specific geographical area, and uses the computing power sunk to edge node to process the massive streaming data generated by autonomous vehicles nearby. The proposed framework is implemented on top of Spark Streaming, which builds up a gray model based traffic flow monitor, a traffic prediction orientated prediction layer and a fuzzy control based Batch Interval dynamic adjustment layer for Spark Streaming. It could forecast the variation of sensors data arrive rate, make streaming Batch Interval adjustment in advance and implement real-time streaming process by edge. Therefore, it can realise the monitor and prediction of the data flow changes of the autonomous driving vehicle sensor data in geographical coverage of edge computing node area, meanwhile minimise the end-to-end latency but satisfy the application throughput requirements. The experiments show that it can predict short-term traffic with no more than 4% relative error in a whole day. By making batch consuming rate close to data generating rate, it can maintain system stability well even when arrival data rate changes rapidly. The Batch Interval can be converged to a suitable value in two minutes when data arrival rate is doubled. Compared with vanilla version Spark Streaming, where there has serious task accumulation and introduces large delay, it can reduce 35% latency by squeezing Batch Interval when data arrival rate is low; it also can significantly improve system throughput by only at most 25% Batch Interval increase when data arrival rate is high. [ABSTRACT FROM AUTHOR]

The catastrophic 2004 Sumatra‐Andaman Mw9.1 earthquake associated with destructive tsunamis has characterized Sumatra as one of the most dangerous convergence zones. Nevertheless, the effects of the thermohydrous state on the strongly coupled megathrust of the incoming plate remain enigmatic. By using a three‐dimensional (3‐D) thermomechanical model to compute the temperature variation and the complicated phase transition process of the water‐bearing descending plate which generates unstable thrust slips, we find that Sumatran earthquakes at varying depths are likely under the control of the inter or intraplate hydrothermal regime, which occurs in or close to the petrological metamorphism transition area. The slab dehydration of the water‐rich mid‐ocean‐ridge basalts (MORB) and the ultramafic rocks in the oceanic lithosphere releases a large amount of fluid to the continental wedge and further facilitates arc magmatism. The fluids are prone to upwelling following the subduction channel along the plate interface and thus contribute to the clustering of earthquakes updip of the dehydration front beneath offshore Sumatra. Brittle failure and dehydration embrittlement at depth, along with the temperature differences caused by variant slab geometry, are conjectured to greatly influence the occurrence of fast and slow earthquakes in Sumatra. Key Points: Sumatran earthquakes are likely under control, and they occur in or close to the area transitioning from petrological metamorphismSlab dehydration of the water‐rich rocks in the oceanic lithosphere release a large amount of fluid to the continental wedgeBrittle failure and dehydration embrittlement have greatly influenced the occurrence of fast to slow earthquakes in Sumatra [ABSTRACT FROM AUTHOR]

The modulation of exciton recombination is one of the core issues for the electronic/optoelectronic devices. Here, we investigate the exciton recombination and surface depletion of ZnO nanowires under various interface conditions in terms of continuum medium mechanics and bond relaxation method. We find that the enhancement of donor concentration, nanowire dimension and external temperature can modify the carrier recombination, surface barrier height and surface depletion depth. Moreover, coated a thin epitaxial layer on the nanowires is of great benefit to reduce the surface state for suppression of recombination rate. The related mechanism on the interface confinement has also been clarified. Our predictions agree well with the experimental measurements, which provide an effective guidance for the organization of electronic device design. [ABSTRACT FROM AUTHOR]

The viscosity of natural gas has considerable theoretical and practical significance in the design and operation of gas transportation, production, and processing. In order to quickly and cheaply obtain the viscosity data of natural gas, an alternate predictive model was developed based on corresponding states and Lennard-Jones averaged intermolecular potential field. Then, the accuracy of the model was assessed with 2389 experimental data points from 15 natural gas specimens after 2000, which sat in temperature and pressure ranges: 241–454 K, 0.1–140 MPa. The result shows that the averaged absolute percent deviation was less than 2.1%, wherein for the 793 data points measured via the same device within 0.5% relative uncertainty, the averaged and maximum absolute percent deviation were ≤ 0.72% and 2.7%. While comparing against ten existing models, the new model had the advantages of simplicity, accuracy, convenience, and theoretical background. In the natural gas viscosity analysis, calculation, and design, the use of the new model is recommended. [ABSTRACT FROM AUTHOR]

A concise bead-based microfluidic system has been developed for joint detection in TORCH screening at point-of-care testing. Assisted by five functionalized polycarbonate single beads, totally five critical infections including TOX, RUB, CMV, HSV-1 and HSV-2 can be simultaneously detected with the microfluidic chip based on chemiluminescence. The microfluidic chip consists of multiple reaction chambers respectively for different reaction steps of the sandwiched chemiluminescence immunoassay, and each reaction chamber is divided into five interconnected independent cells to respectively hold five single beads in different position. With a guiding path, each single bead with a ferrous core can be easily transported between each two adjacent reaction chambers through magnetic control to consecutively react with the serum sample or other different reagents. Meanwhile, with magnetic control, each single bead within the reaction chamber can be moved back and forth to improve the detection sensitivity with enhanced mixing. In one time test, joint detection with five infections to one serum sample can be simultaneously implemented by introducing synchronous manipulation to five single beads. Chemiluminescence signal from five single beads is collected by a sensitive CCD camera in parallel. Qualitative detection is achieved by comparing the detection signal amplitude with the corresponding cutoff value for each infection. Experimental results show that accurate, simple, convenient and efficient TORCH screening can be achieved with the easy-to-operate and low-cost microfluidic system at resource-poor settings. [ABSTRACT FROM AUTHOR]

Through general property tests, rheological measurements, SEM observations and weight changes after immersion, electrochemical methods and water vapor transmission tests, a waterborne zinc-rich coating from sodium silicate solution catalyzed by ammonium acetate was characterized. Results showed that the formula catalyzed by ammonium acetate overcame the poor water resistance of other non-catalyzed coatings, while binding the zinc powder in the film. The zinc-rich film had the basic features required for a zinc-rich primer to be useful and was electrochemically cathodically protective during tests. The acetate anion from ammonium acetate resulted not only in little early corrosion while catalyzing the formation of zinc silicate before cure but also stronger corrosion protection during the immersion test on the cured film. The velocity of water vapor transmission and the amount of acetate anions present decreased with time until a stable value was achieved after approximately 6 days. [ABSTRACT FROM AUTHOR]

Based on symmetric intermolecular interactions approximation, a novel relation between compressibility (Z) factor of hydrocarbon gases and molecular potential has been developed. The relation indicated that the Z factor was an exponential function of the depth of potential well, which was derived to be proportional to the molecular potential. By this relation, the reduced molecular potentials of methane, ethane, and propane were determined at the same temperature. The obtained reduced potentials appeared the standard L-J curve shape, suggesting the rationality and success of this approximation and showing the academic significance of the relation in estimating molecular potential. [ABSTRACT FROM AUTHOR]

Neural network is one of the branches with the most active research, development and application in computational intelligence and machine study. Radial basis function neural network (RBFNN) has achieved some success in more than one application field, especially in pattern recognition and functional approximation. Due to its simple structure, fast training speed and excellent generalization ability, it has been widely used. Artificial fish swarm algorithm (AFSA) is a new swarm intelligent optimization algorithm derived from the study on the preying behavior of fish swarm. This algorithm is not sensitive to the initial value and the parameter selection, but strong in robustness and simple and easy to realize and it also has parallel processing capability and global searching ability. This paper mainly researches the weight and threshold of AFSA in optimizing RBFNN. The simulation experiment proves that AFSA-RBFNN is significantly advantageous in global optimization capability and that it has outstanding global optimization ability and stability. [ABSTRACT FROM AUTHOR]

This study performs various thermal treatments on Indium Tin Oxide (InO + SnO) films, which are the transparent conducting layers for GaN light emitting diodes (LEDs). Structural characterization by high-resolution transmission electron microscopy (HRTEM) indicates that the ITO films have the least crystalline grain boundary and greatest grain size after thermal treatment at 580 °C for 10 min, which gives a minimum forward voltage of LEDs of 2.95 V and the maximum light output power of LEDs is 177.51 mW at 125 mA. The high output intensity in the near horizontal direction is also greater than that for treatment at other temperatures. [ABSTRACT FROM AUTHOR]

Based on statistical mechanics, a theoretical model for the density and temperature-dependent viscosity of hydrocarbon gas has been developed. In the model, the averaged intermolecular attractive potential was suggested as a power function of density, and the viscosity was derived as an exponential function of the potential. In the evaluation, the derived equation was found in good agreement with reliable literature data with averaged and maximum absolute percent deviations of 0.34% and 0.98%, and comprehensively performed better than several selected methods. The performances showed the success of the theoretical model, and revealed application potentials in the natural gas industry. [ABSTRACT FROM AUTHOR]

A high‐efficiency photocatalyst is critical for water splitting by solar light. Herein, via first principles calculations, the 2D polarized GeS/MoSe2 van der Waals (vdW) heterostructure is proposed as an efficient water redox photocatalyst. The performance of GeS/MoSe2 heterostructure is better than isolated materials, as the properties of GeS monolayer and MoSe2 monolayer are complementary by forming vdW heterostructure. GeS/MoSe2 heterostructure possesses suitable bandgap, dipole‐induced internal electric field, and excellent solar absorption performance. The band alignments of GeS/MoSe2 heterostructure are suitable compared with the redox potential of water. It is feasible to tune the optoelectronic properties and enhance photocatalytic activity of GeS/MoSe2 heterostructure via strain engineering. Biaxial compressive strain range from −2% to −3% induces the direct bandgap characteristic in GeS/MoSe2 heterostructure. The results suggest that 2D polarized GeS/MoSe2 vdW heterostructure is a potential novel high‐efficiency photocatalyst for water splitting under a wide range of spectra from ultraviolet to near infrared. [ABSTRACT FROM AUTHOR]

With ultrahigh carrier mobility and large band gap, blue phosphorene (bP) is a promising photoelectronics surpassing black phosphorene and can be further improved by heterostacking. Herein, strain‐engineering of the electronic band gaps and light absorption of two van der Waals heterostructures bP/MoS2 and bP/MoSe2 via first‐principles calculations has been reported. Their electronic band structures are sensitive to in‐plane strains. It is interesting and beneficial that biaxial compressive strain range of −0.02 to −0.055 induces the direct band gap in bP/MoSe2. There are two critical strains for bP/MoS(Se)2 heterostructures, where the semiconductor–metal transition can be observed. The bP/MoS(Se)2 heterostructures exhibit strong visible–ultraviolet light absorption, which can be further enhanced via biaxial strain. Our results suggest that bP/MoS(Se)2 heterostructures have promising electronics and visible–ultraviolet optoelectronic applications. [ABSTRACT FROM AUTHOR]