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The existence of related faults between components brings great difficulties to the analysis of the importance of system components. How to quantify the influence of related faults and evaluate the importance of components is one of the hot issues in current research. In this paper, under the assumption that the fault propagation obeys the Markov process, the PageRank algorithm is integrated into the decision-making trial and evaluation laboratory (DEMATEL). On the basis, the calculation of influencing degree and influenced degree between components is studied to quantify the influence of related faults, and the problem of subjective evaluation of weight coefficient in traditional DEMATEL is solved. The rationality is verified through the method of combining the Interpretative Structural Modeling Method (ISM) and direct relation matrix. The importance of system related faults is identified accurately based on the calculation of center degree and cause degree, and the central-related faults of CNC machine tools are analyzed as an example to verify the effectiveness of the proposed method.

Art design is a method of conveying human feelings and emotions, particularly via the use of visual structures such as paintings or sketches. Every element of our life, including arts and crafts, has been positively affected by the introduction of novel technologies such as artificial intelligence (AI) and machine learning (ML). In today's modern environment, these technologies have altered the techniques of art creation, consumption, and distribution. In today's environment, ML and human emotions are the two most important aspects for interactive and high‐quality art design. Whereas traditional learning systems can be extremely effective in the teaching and learning process of art‐related subjects, AI and ML can be very effective in the teaching and learning process of art‐related subjects for the advancement of learners' artistic skills. The productive and active role of AI and ML in the developments and advancements of art design has been given a very comprehensive and detailed overview in this study. Following a detailed examination of the existing techniques, distinct characteristics have been identified. Six of the most widely utilized features were chosen from the literature to execute the analytical hierarchy process (AHP). For ranking the options based on the weights derived by AHP, the TOPSIS algorithm is used. The option with the best performance came in first, whereas the one with the worst performance came in last. [ABSTRACT FROM AUTHOR]

Peanut oil body emulsion occurs during the process of aqueous enzymatic extraction (AEE). The free oil is difficult to release and extract because its structure is stable and not easily destroyed. Demulsification can release free oil in an oil body emulsion, so various fatty acids were selected for the demulsification. Changes in the amount of heptanoic acid added, solid–liquid ratio, reaction temperature, and reaction time were adopted to investigate demulsification, and the technological conditions of demulsification were optimized. While the optimal conditions were the addition of 1.26% of heptanoic acid, solid–liquid ratio of 1:3.25, reaction temperature of 72.7 °C, and reaction time of 55 min, the maximum free oil yield was (95.84 ± 0.19)%. The analysis of the fatty acid composition and physicochemical characterization of peanut oils extracted using four methods were studied during the AEE process. Compared with the amount of oil extracted via other methods, the unsaturated fatty acids of oils extracted from demulsification with heptanoic acid contained 78.81%, which was significantly higher than the other three methods. The results of physicochemical characterization indicated that the oil obtained by demulsification with heptanoic acid had a higher quality. According to the analysis of the amino acid composition, the protein obtained using AEE was similar to that of commercial peanut protein powder (CPPP). However, the essential amino acid content of proteins extracted via AEE was significantly higher than that of CPPP. The capacity of water (oil) holding, emulsifying activity, and foaming properties of protein obtained via AEE were better than those for CPPP. Overall, heptanoic acid demulsification is a potential demulsification method, thus, this work provides a new idea for the industrial application of simultaneous separation of oil and proteins via AEE. [ABSTRACT FROM AUTHOR]

The structure, characteristics and working principle of extrinsic F-P sensor were introduced in details, and application of the extrinsic F-P sensor in gas detection system was expounded. The sensor takes hollow core photonic crystal fiber as isotopic carrier, is not affected by environmental temperature, which has characteristics such as high sensitivity, strong anti-jamming capability and low transmission loss, and can significantly improve accuracy and precision of gas concentration detection.

With the acceleration of industrialization, the removal of refractory organic dyes from water and how to promote its practical application remains a challenge. Herein, we synthesized an FeCo-LDH/LI-NDG composite electrode material by a simple laser-induced technique on polyimide films, which could electrocatalytically activate peroxymonosulfate (PMS) to completely degrade MB in about 6 min. The reaction rate constant (kobs) was 0.461 min−1. It was faster than most of the currently reported electrocatalysts. The reaction system demonstrated good interference resistance and catalytic effectiveness in the pH range of 3 to 9. According to the chemical quenching and electron paramagnetic resonance (EPR) experiments, the non-radical pathway of 1O2 and the radical pathways of SO4·−, ·OH and O2·− were involved in the reaction synergistically, with 1O2 playing the dominant role. 1O2 was produced through the dual pathway of PMS electron loss at the anode and O2·− intermediate transformation at the cathode. The two activation methods of electro-activation and catalytic activation of PMS had synergistic effects to achieve high efficiency in the whole process of production, reaction and recovery, providing new ideas to advance practical applications. [ABSTRACT FROM AUTHOR]

Rational design of composite nanostructured photocatalytic systems with good sunlight absorption capacity and efficient charge separation and transfer ability is an urgent problem to be solved in photocatalysis research. Here, a ZnMn2O4 decorated three-dimensional carbon nitride with O, C co-doping, and nitrogen defect composite photocatalytic system was prepared using a simple hydrothermal method and subsequent calcination method. For the photocatalytic reactions, the presence of heterostructures, C, O co-doping, and nitrogen defects greatly promotes the separation and transfer of charges at the semiconductor/semiconductor interface under the local electric field, thereby extending its service life. The photocatalytic degradation efficiency of sulfamethoxazole in water is as high as 94.3% under the synergistic effects, which is also suitable for the complex water environment. In addition, the synthesized photocatalyst has good chemical stability and recyclability. This study provides a new opportunity to solve the problem of environmental pollution. [ABSTRACT FROM AUTHOR]

Fracture-vuggy oil reservoirs contain micrometer-sized dissolved secondary pores, fractures, and meter-sized karst caves. Generally, the researches on the flow mechanism of fractured-vuggy reservoirs are based on the assumption of karst cave-fracture-matrix triple medium that gives a partial differential equation which the pressure satisfies. This triple medium flow equation lays the basics for the well testing theory of fractured-vuggy reservoirs. However, the triple medium equation cannot reflect the actual existence of the karst cave volume in geology. Recently, we proposed a theory of fracture-cave seepage flow coupled with vug pressure wave which takes the vug size into consideration and thus can better describe the fracture-vuggy reservoirs. On the basis of this theory, this work combines the change of formation pressure with time, Duhamel's theorem, and well testing theory to obtain the mathematical expression of time-varied bottom hole pressure and flow rate in Laplace space. Then, the dynamic inflow performance relationship (IPR) curve of fractured-vuggy reservoir is obtained by inverse Laplace transformations. This dynamic IPR curve can predict the productivity for fractured-vuggy reservoirs using parameters from well test interpretations of pressure recovery. The correctness of this productivity prediction method is verified by filed fractured-vuggy oil well. This productivity prediction method not only utilizes and expands the application of well test interpretation data but also shortens the test time and reduces test costs, which is important for oil development. [ABSTRACT FROM AUTHOR]

Sea temperature structures are important for water stratification and marine ecosystems. In the coastal water of Muping, China, stationary measurements of sea temperature captured temporal temperature changes during two summer storm events. The north component of the wind during the two storms was opposite. The temperature responded differently to wind directions in the two storm events. A well-validated numerical ocean model was used to investigate the mechanism of sea temperature variation of the coast of Muping. The model revealed that the southerly and easterly wind was upwelling-favorable in the study area. They generated the shoreward transport of bottom cold water, which induced bottom water cooling, enhanced stratification, and weakened vertical mixing. On the other hand, the northerly and westerly wind was downwelling-favorable and enhanced turbulent mixing. The alongshore upwelling-favorable wind caused more cross-shore transport than cross-shore upwelling-favorable wind, which resulted in stronger bottom cooling. Similarly, alongshore downwelling-favorable wind generated lower temperature than cross-shore wind. A surface cold-water band was formed in the second storm. Although it was formed during upwelling-favorable wind, the temperature balance analysis indicated that vertical mixing and westward horizontal advection were the two dominant processes compared to upwelling. [ABSTRACT FROM AUTHOR]

The bead-on-a-string structure has been widely observed in many fractured vuggy carbonate reservoirs, especially in Shunbei oilfield, northwestern China. To date, there are still no appropriate well test methods for analyzing these reservoirs with the vertical bead-on-a-string structure. This paper proposes a new theoretical well test model, which considers the gravity effect and the natural fractures connecting the vuggs, to analyze this kind of reservoirs. First, we establish the mathematical model of fractured vuggy reservoirs with the vertical bead-on-a-string structure. With the different outer boundary conditions, Laplace transform and inversion are employed to solve the well test model. Then, the type curves for the well test model are plotted and discussed. It is found that the gravity effect can be equivalent to a type of constant pressure boundary condition. Take the three-region-two-cave as an example, type curves can be divided into nine distinct flow regimes, including wellbore storage, skin, linear flow I and II, transition flow I and II, vug storage I and II, and boundary flow. The transition flow and vug storage period are named as the vug storage effect. Subsequently, the effects of relevant parameters are studied. It is concluded that the depth of the drop during vug storage effect increases with increasing dimensionless vug storage constant C vD and dimensionless vug height z D 2 - z D 1 ; the greater dimensionless gravity effect coefficient G D leads to the smaller equivalent boundary distance of the constant pressure boundary condition; the smaller the mobility ratio M 12 , the earlier the appearance of the second linear flow regime; the larger the storage ratio ω 12 , the more distinct the vug storage effect. Finally, two field case studies are carried out by using the proposed method. The locations and volumes of the caves are estimated, which shows that the proposed theoretical well test model has a great potential of obtaining the formation and cave parameters accurately. However, there is not available data that enable an accurate description of the locations and volumes of the caves by now, the proposed model still needs further field verifications. • A new mathematical model of fractured vuggy carbonate reservoirs considering the gravity effect is established. • It is found that the gravity effect can be equivalent to a type of constant pressure boundary condition. • Two filed cases show the great potential of the proposed method to the fractured vuggy carbonate reservoirs. [ABSTRACT FROM AUTHOR]