Spatio-Temporal Deformable Attention Network for Video Deblurring

The key success factor of the video deblurring methods is to compensate for the blurry pixels of the mid-frame with the sharp pixels of the adjacent video frames. Therefore, mainstream methods align the adjacent frames based on the estimated optical flows and fuse the alignment frames for restoration. However, these methods sometimes generate unsatisfactory results because they rarely consider the blur levels of pixels, which may introduce blurry pixels from video frames. Actually, not all the pixels in the video frames are sharp and beneficial for deblurring. To address this problem, we propose the spatio-temporal deformable attention network (STDANet) for video delurring, which extracts the information of sharp pixels by considering the pixel-wise blur levels of the video frames. Specifically, STDANet is an encoder-decoder network combined with the motion estimator and spatio-temporal deformable attention (STDA) module, where motion estimator predicts coarse optical flows that are used as base offsets to find the corresponding sharp pixels in STDA module. Experimental results indicate that the proposed STDANet performs favorably against state-of-the-art methods on the GoPro, DVD, and BSD datasets.Comment: ECCV 202

Construction of a Fish-like Robot Based on High Performance Graphene/PVDF Bimorph Actuation Materials.

Smart actuators have many potential applications in various areas, so the development of novel actuation materials, with facile fabricating methods and excellent performances, are still urgent needs. In this work, a novel electromechanical bimorph actuator constituted by a graphene layer and a PVDF layer, is fabricated through a simple yet versatile solution approach. The bimorph actuator can deflect toward the graphene side under electrical stimulus, due to the differences in coefficient of thermal expansion between the two layers and the converse piezoelectric effect and electrostrictive property of the PVDF layer. Under low voltage stimulus, the actuator (length: 20 mm, width: 3 mm) can generate large actuation motion with a maximum deflection of about 14.0 mm within 0.262 s and produce high actuation stress (more than 312.7 MPa/g). The bimorph actuator also can display reversible swing behavior with long cycle life under high frequencies. on this basis, a fish-like robot that can swim at the speed of 5.02 mm/s is designed and demonstrated. The designed graphene-PVDF bimorph actuator exhibits the overall novel performance compared with many other electromechanical avtuators, and may contribute to the practical actuation applications of graphene-based materials at a macro scale

Wetland Degradation and Ecological Restoration

Wetlands are among the most important ecosystems on earth and functioned as the “kidneys” of the earth, which play an important role in maintaining ecological service functions. However, with the rapid growth in human populations, wetlands worldwide are suffering from serious degradation or loss as affected by wetland pollution, wetland reclamation, civilization and land use changes, and so forth. Wetland degradation has potential influences on human health, biodiversity, regional climate, and regional ecological security. Therefore, it is an urgent task to recover these degraded wetlands. In recent years, wetland protection, restoration, and its reasonable exploitation have been paid much more attention to by most governments and researchers. Moreover, wetland restoration has become the frontier fields of wetlands science, which has been listed as one of important themes in these recent international wetlands and ecological conferences. Understanding wetland degradation processes can contribute to better effective wetland restoration. Therefore, we organized this special issue on “wetland degradation and ecological restoration.” The objective of this special issue is to emphasize the effects of human activities on wetland ecosystems, the relationships between soil, water, and plant in wetlands, and wetland restoration issues and applications

Bacillus cereus, a potential pathogen of snakehead fish Ophiocephalus argus

Bacillus cereus is an emerging pathogen that has caused high mortalities in aquaculture animals. Yet the pathogenicity of B. cereus in snakehead fish Ophiocephalus argus is still unclear. In this study, a virulent strain (CA4) was isolated from diseased snakehead fish suffering from a typical symptom of hepatic hemorrhage with blood vessel congestion and macrophage infiltration, and was identified molecularly and phenotypically as B. cereus. It was β-hemolytic, showed an LD50 value of 2.57×106 CFU mL-1 for snakehead fish, and developed multiple resistances to cotrimoxazole, doxycycline, florfenicol, neomycin, sulfisoxazole, and tetracycline in aquaculture use. To the best of our knowledge, this is the first report of snakehead fish- pathogenic B. cereus. The findings of this study provide new insights into the potential threat of pathogenic B. cereus to snakehead fish

Construction and Application of “Active Prediction-Passive Warning” Joint Impact Ground Pressure Resilience Prevention System: Take the Kuan Gou Coal Mine as an Example

AbstractWith the increasing depth and intensity of coal mining, the impact on ground pressure has become one of the main disasters facing mining, seriously threatening mine safety. Introducing the concept of toughness urban design, building a joint toughness prevention and control system based on active prediction and analysis of the impact pressure risk at the back mining face according to the geological deposit conditions and mining technology conditions and passive warning using monitoring data to explore the impact precursor characteristics is an important basis for impact pressure management and has important engineering significance to ensure the safe back mining. In this paper, firstly, the whole working face is divided into small unit areas, and the BP neural network prediction model is constructed to predict and analyze each small unit separately, and the distribution of impact ground pressure hazard level in different areas of the working face is derived. Next, a FLAC numerical model was established to analyze the stress distribution and migration characteristics at different retrieval distances of the working face and to explore the main distribution areas of impact hazard. Finally, the trend method, critical value method, and dynamic rate of change method were applied to determine the early warning indicators of impact ground pressure in the Kuan Gou coal mine, establish a comprehensive early warning method of impact ground pressure applicable to the Kuan Gou coal mine, and carry out field application with good effect. The findings of this paper have good scientific significance and reference value for promoting impact hazard analysis and early warning in mines with similar geological conditions and mining technology conditions in China

Study on overlying strata containing primary fractures migration and spatial-temporal characteristics of water gushing (leaching) caused by mining field disturbance

The super-thick, high-pressure, medium-strong water-rich Luohe Formation aquifer is overlying in the Binchang mining area of Shanxi Province, and the fractures in the overlying rock are developed, it makes the water channel easier to communicate with the aquifer and stope of Luohe Formation, resulting in the increase of water inflow and area in the stope. In order to study the morphological characteristics of water inrush induced by the network of water-conducting channels formed by primary fractures communicating with the aquifer of the thick Luohe Formation under the influence of mining, the solid-flow coupling similar material simulation test was carried out based on the similar simulation physical experiment system of water-sand inrush in overburden rock. The results show that when the working face is advanced to 140 m, the lower strata of the bed separation are broken in advance due to the influence of the primary fractures. The left incomplete bed separation space and the triangular space formed by the right cantilever beam support form the “Z” bed separation space. When the working face is advanced to 160 m, two “Z-type” bed separation spaces are developed in the overlying strata, which are interconnected with the primary fractures and mining-induced fractures to form a water channel network. The form of gushing (leaching) water in the stope changed from ‘ drip-drip and flow-flow-multi-state ’, and the overall gushing (leaching) water volume increased first and then decreased. The water pressure of overlying strata and the advancing distance of the working face show a segmented evolution characteristic of decreasing first and then increasing. The minimum interval and the position of the inflection point of the segmentation increase with the increase of the distance between the monitoring point and the open-off cut. The final water pressure values near the central area of the goaf are greater than the two boundary monitoring points. The analysis results show that the existence of primary fractures promotes the development of water-conducting fracture channel network, accelerates the process of water transport, and induces the formation and development of water gushing (leaching) in the stope. The research results clarify the influence of primary fractures on the distribution characteristics of water conduction channel network and the evolution law of water gushing (leaching) form morphology, and explain the conduction mechanism of thick and high confined aquifer water to stope water inrush

A smart knowledge deployment method for the conceptual design of low-carbon products

As the consciousness of the global environment and sustainability has increased, low-carbon products have played a vital role in the transformation to a circular economy. Advanced smart design technology has enabled product designers to fulfill customer requirements by offering tailor-made functions and low-carbon solutions. However, although the existing approaches used in the conceptual design process can help in functional reasoning, knowledge modelling, and scheme evaluation, the smart reuse of knowledge, such as in design model improvement and concept scheme iteration for lower carbon emission, the corresponding process evaluation concerning carbon footprint has not been given sufficient attention. To resolve this, in this work, a smart knowledge deployment method is proposed for reasoning, configuring, and optimizing the conceptual scheme (CS) based on carbon emission evaluation and interaction. First, to match discretized knowledge, sub-function requirements after function decomposition are mapped with granular clustered knowledge into a matrix based on a requirement function knowledge deployment (RFKD) model. Second, the derived candidate concept schemes (CCSs) are selected in three steps: conflict-based primaries, configuration, and carbon footprint ranking. Finally, the initial conceptual scheme (ICS) with the lowest carbon emission is used as input for the interactive genetic algorithm (IGA) to better capture a comprehensive set of user feedback on potential candidate schemes through interactions. Accordingly, improvements are completed as intended. The prototype design and an experimental study of a brand-new friction-wear testing machine are conducted. The results suggest that the proposed approach could effectively reduce the carbon emissions of products obtained through CS and improve the convergence of the schemes produced via genetic operation

Precursor Information Recognition of Rockburst in the Coal-Rock Mass of Meizoseismal Area Based on Multiplex Microseismic Information Fusion and Its Application: A Case Study of Wudong Coal Mine

AbstractIn recent years, the rockburst induced by steeply inclined coal seam mining in the Urumqi mining area has become serious. In this paper, the evolution law of multiplex microseismic information before and after the rockburst is obtained through in-depth mining of the field microseismic data. In addition, the evolution characteristics of microseismic activities before and after the rockburst of steeply inclined coal-rock mass in the meizoseismal area are revealed from three important scales: time, space, and strength. The results show the following: (1) The microseismic activity of the Wudong Coal Mine is mainly of stress migration type. The sandwiched rock pillar is the primary inducement of rockburst, and the b value decreases greatly with the mining progresses (by 23.9%). It indicates that the risk of rockburst induced by the local failure of rock mass in this area is increasing. (2) From the time scale and strength index, the precursory indexes of rockburst are put forward, respectively: ① the daily total energy and the frequency of microseisms suddenly rise and fall rapidly at the same time in the shock start-up period (5 days before rockburst), and the daily total energy of microseisms decreases to the abnormal valley value within 30 days. ② The abnormal growth rate of microseismic events exceeded 60% in a certain stage, and “induced shock events” appeared. (3) The shock risk is positively correlated with the decline rate of energy index, the growth rate of cumulative apparent volume, and Schmidt. It is determined that the rockburst will occur within 19 days after entering the shock early warning period. The results of prediction examples show that this method has a good prediction effect on rockburst in strong meizoseismal areas, which can provide a reference for rockburst prevention in the mining process in strong meizoseismal areas