The movement of global ocean circulation in the Earth’s main magnetic field generates a measurable induced magnetic field(about 2 nT at geomagnetic satellite altitudes).However,this ocean circulation-induced magnetic...
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The movement of global ocean circulation in the Earth’s main magnetic field generates a measurable induced magnetic field(about 2 nT at geomagnetic satellite altitudes).However,this ocean circulation-induced magnetic field has not been previously estimated or incorporated into geomagnetic field models,potentially causing leakage into the core field ***,we present a method to account for the circulation-induced magnetic field during geomagnetic field ***,a forward model of the circulation-induced magnetic field is constructed by numerically solving electromagnetic induction equations based on a realistic ocean circulation ***,this forward model is subtracted from the observed ***,the core and lithospheric fields,magnetospheric and Earth’s mantle-induced fields,and the ocean tide-induced magnetic field are *** our method to over 20 years of MSS-1,Swarm,CryoSat-2,and CHAMP satellite magnetic data,we derive a new multisource geomagnetic field model(MGFM).We find that incorporating a forward model of the circulation-induced magnetic field marginally improves the fit to the ***,we demonstrate that neglecting the circulation-induced magnetic field in geomagnetic field modeling results in leakage into the core field *** highlights of the MGFM model include:(i)a good agreement with the widely used CHAOS model series;(ii)the incorporation of magnetic fields induced by both ocean tides and circulation;and(iii)the suppression of leakage of the circulation-induced magnetic field into the core field model.
Tropical Cyclone (TC) estimation aims to estimate various attributes of TC in real-time to alleviate and prevent disasters caused by violent TCs. As artificial intelligence technology advances, various deep learning-b...
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The process control-oriented threat,which can exploit OT(Operational technology)vulnerabilities to forcibly insert abnormal control commands or status information,has become one of the most devastating cyber attacks i...
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The process control-oriented threat,which can exploit OT(Operational technology)vulnerabilities to forcibly insert abnormal control commands or status information,has become one of the most devastating cyber attacks in industrial automation *** effectively detect this threat,this paper proposes one functional pattern-related anomaly detection approach,which skillfully collaborates the BinSeg(Binary Segmentation)algorithm with FSM(Finite State Machine)to identify anomalies between measuring data and control *** detecting the change points of measuring data,the BinSeg algorithm is introduced to generate some initial sequence segments,which can be further classified and merged into different functional patterns due to their backward difference means and *** analyzing the pattern association according to the Bayesian network,one functional state transition model based on FSM,which accurately describes the whole control and monitoring process,is constructed as one feasible detection ***,we use the typical SWaT(Secure Water Treatment)dataset to evaluate the proposed approach,and the experimental results show that:for one thing,compared with other change-point detection approaches,the BinSeg algorithm can be more suitable for the optimal sequence segmentation of measuring data due to its highest detection accuracy and least consuming time;for another,the proposed approach exhibits relatively excellent detection ability,because the average detection precision,recall rate and F1-score to identify 10 different attacks can reach 0.872,0.982 and 0.896,respectively.
The success of deep face recognition (FR) systems has raised serious privacy concerns due to their ability to enable unauthorized tracking of users in the digital world. Previous studies proposed introducing impercept...
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Legal Judgment Prediction (LJP) aims to form legal judgments based on the criminal fact description. However, researchers struggle to classify confusing criminal cases, such as robbery and theft, which requires LJP mo...
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Electrodialysis (ED) technology for waste acid treatment has high economic efficiency and environmentally friendly advantages. The primary limitation of ED in the retrieval of low-concentration spent acids lies in the...
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Electrodialysis (ED) technology for waste acid treatment has high economic efficiency and environmentally friendly advantages. The primary limitation of ED in the retrieval of low-concentration spent acids lies in the leakage of hydrogen ions through anion exchange membranes (AEMs) due to its extremely small size and high mobility. To address this issue, a series of AEMs named QPAB-x (x = 3, 5, 7, 10) were designed for acid concentration in ED process by increasing the membrane densities through in situ crosslinking in this study. The successful synthesis of polymers was confirmed through 1H nuclear magnetic resonance hydrogen (1H NMR) spectroscopy and Attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy. Furthermore, ATR-FTIR spectroscopy showed that the higher the side chain content, the higher the crosslinking degree of the membranes. X-ray photoelectron spectroscopy (XPS) was employed to characterize the effects of aqueous and acidic environments on QPAB membranes. The performance disparities between QPAB-x membranes in acidic and aqueous environments were examined separately. Subsequently, the influence of crosslinking degree on the acid-blocking capability of the membranes was thoroughly investigated by conducting ED acid-concentration experiments to monitor the hydrogen ions concentration process and determine the current efficiency and energy consumption of the QPAB-x membranes. Our experimental results demonstrated that QPAB-x membranes with higher cross-linking degrees have lower water content, especially the QPAB-10 membrane with an IEC of approximately 1.5 mmol g-1 and a remarkably low water content of around 10%. This leads to a reduced H+ transfer number and excellent acid-blocking properties. Additionally, compared to commercial membrane A2, using the QPAB-10 membrane in the ED process resulted in a higher final H+ concentration in the concentrated chamber. Consequently, these synthesized membranes exhibit considerable promis
Isosorbide is a novel bio-based material derived as a secondary dehydration product of *** work focuses on the kinetics of sulfuric acid-catalyzed dehydration of sorbitol under conditions of nonconstant ***,the effect...
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Isosorbide is a novel bio-based material derived as a secondary dehydration product of *** work focuses on the kinetics of sulfuric acid-catalyzed dehydration of sorbitol under conditions of nonconstant ***,the effects of stirring rate,catalyst dosage,reaction temperature,and reaction time on the dehydration reaction of sorbitol were *** yield of isosorbide up to 77.13%was obtained after 1.5 h of reaction time under conditions of 2 kPa,1.0%(mass)catalyst dosage,and 413.15 *** on the sorbitol dehydration reaction mechanism and a simplified reaction network,a kinetic model was developed in this work.A good agreement was accomplished between kinetic modeling and experiments between 393.15 and 423.15 *** fitting results indicate that side reactions with higher activation energies are more affected by reaction temperatures,and the main side reaction that influences the selectivity of isosorbide is the oligomerization reaction among the primary dehydration products of *** model fitting of the catalyst amounts effect shows that the effective concentration of sulfuric acid would be reduced with the increase of dosage due to the molecular agglomeration ***,the kinetic experiments and modeling results obtained in this work will be helpful to the design and optimization of the industrial sorbitol dehydration process.
The attitude tracking control with unwinding-free performance for rigid spacecraft is studied in this article. A full-state feedback control law based on a hyperbolic sine function is developed such that the resulted ...
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Additive manufacturing of aluminum alloys has received significant attention in the aerospace industry;however,achieving sufficient high strength,especially at elevated temperatures,remains ***,a crack-free and near-f...
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Additive manufacturing of aluminum alloys has received significant attention in the aerospace industry;however,achieving sufficient high strength,especially at elevated temperatures,remains ***,a crack-free and near-full dense Al-1Fe-0.6Cu-1.3Zr alloy was fabricated by the laser powder bed fusion(LPBF)*** Al-Fe-Cu-Zr alloy exhibits heterogeneous microstructures with two distinct *** is the so-called coarse-grain zones(CGZs)with an average grain size of 0.95μm,where(Al,Cu)Fe_(3) nanoparticles precipitate in the Al matrix and Fe and Cu cosegregate at the grain boundaries(GBs).The other is fine-grain zones(FGZs)with an average grain size of 0.45μm,where an Al 3 Zr nanoparti-cle precipitates in each of theα-Al grains(serves as the nuclei),and Fe-rich nanoprecipitates and Fe/Cu cosegregation appear at the *** a result,the LPBF Al-Fe-Cu-Zr alloy,with these unique heteroge-neous structures,displays high strength at both room temperature and elevated temperatures,e.g.,with high yield strengths of 500 MPa at room temperature,and 163 MPa at 573 K,both are higher than those of additive manufactured Al-based alloys reported thus *** is suggested that the high strength over a wide temperature range of the current LPBF Al alloy is mainly attributed to the combination of the precipitation strengthening mechanism and grain-boundary strengthening mechanism.
Thermal energy storage(TES)using phase change materials(PCMs)is a powerful solution to the improvement of energy *** application of Ammonium alum(A-alum,NH4Al(SO_(4))_(2)·12H_(2)O)in the latent thermal energy sto...
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Thermal energy storage(TES)using phase change materials(PCMs)is a powerful solution to the improvement of energy *** application of Ammonium alum(A-alum,NH4Al(SO_(4))_(2)·12H_(2)O)in the latent thermal energy storage(LTES)systems is hampered due to its high supercooling and low thermal *** this work,modified A-alum(M-PCM)containing different nucleating agents was prepared and further adsorbed in expanded graphite(EG)to obtain composite phase change material(CPCM)to overcome the disadvantages of *** properties,thermal cycle stability,microstructure and chemical compatibility of CPCM were characterized by differential scanning calorimetry,thermal constant analysis,scanning electron microscopy,X-ray diffraction and Fourier transform infrared *** cold rewarming phenomenon of CPCM was established and *** showed that the latent heat and melting point of CPCM were 187.22 J/g and 91.54℃,*** supercooling of CPCM decreased by 9.61℃,and thermal conductivity increased by 27 times compared with pure *** storage and release tests indicated that 2 wt%calcium chloride dihydrate(CCD,CaCl_(2)·2H_(2)O)was the optimum nucleating agent for *** result of TG and 30 thermal cycles revealed that CPCM exhibited favorable thermal stability and reliability during the operating *** prepared modified A-alum/EG CPCM has a promising application prospect for LTES.
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