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Due to the difference in load characteristics and influencing factors in large-scale distribution transformer load forecasting, if all the distribution transformers share a unified model, the prediction accuracy is low, and if the model is built for each distribution transformer, the computational resources will be excessively consumed. An Attention-LSTM short-term forecasting method of distribution load based on multi-dimensional clustering is proposed. The non-parametric kernel method is used to perform probability fitting on the daily load characteristics to form a typical daily load sequence. Improved two-level clustering is applied for load clustering, taking the Euclidean warping distance and influence factors as the similarity evaluation criteria. AP clustering is utilized for obtaining similar time-series, and training sets are formed to train the Attention-LSTM model. Different Attention-LSTM models are obtained by training for different distribution load types and time-series. The effectiveness and practicability of the method proposed are verified by the load data and meteorological data of a municipal distribution network. The accuracy rate is increased by 2.75% and the efficiency is increased by 616.8%.

With the rapid technological advances in hydraulic fracturing, the economic development of ultra-tight gas/oil reservoirs becomes feasible, altering current energy image between demand and supply. The key parameter evaluating the artificial hydraulic fracture is the long-term conductivity, manifesting the transport capacity for reservoir fluids. The majority of previous contributions focused on the impacts of inherent proppant properties on long-term fracture conductivity, while the influence induced by mixture proppants with a wide range of particle size has not received due attention. In particular, as for the realistic field case, multiple types of proppants with diverse particle sizes are utilized to reach desirable conductivity. At the same time, the stress conditions inevitably change within the depressurization development process, leading to the evident enhancement of closing pressure towards artificial fracture, acting as the detrimental role for long-term fracture conductivity. As a result, it is dramatically necessary and urgent to reveal the mutual influence arising from mixture proppants as well as closing pressure. In order to address this issue, series of laboratory experiments are implemented, and comprehensive theoretical analysis in terms of experimental data is performed. Results show that (a) reduction of particle size is observed with increasing closing pressure, the average decreasing rate approaches 19.3%; (b) Closing pressure acts as a detrimental role impairing conductivity, the amplitude is able to reach 42.1% as for the mixture case with a relatively high proportion of mesh-20/40 particles; (c) Mixing proppants uniformly fails to enhance fracture conductivity effectively, and the forward segmentation is demonstrated as the suitable strategy and beneficial for fluid transport capacity. The contribution expects to advance current understanding regarding the impact of mixture proppants on long-term fracture conductivity.

As cache-based side-channel attacks become serious security problems, various defenses have been proposed and deployed in both software and hardware. Consequently, cache-based side-channel attacks on processes co-residing on the same core are becoming extremely difficult. Most of recent attacks then shift their focus to the last-level cache (LLC). Although cache partitioning is currently the most promising defense against the attacks abusing LLC, it is ineffective in thwarting the side-channel attacks that automatically create eviction sets or bypass the user address space layout randomization. In fact, these attacks are largely undefended in current computer systems. We propose Remapped Cache Layout (\textsf{RCL}) -- a pure hardware defense against a broad range of conflict-based side-channel attacks. \textsf{RCL} obfuscates the mapping from address to cache sets; therefore, an attacker cannot accurately infer the location of her data in caches or using a cache set to infer her victim's data. To our best knowledge, it is the first defense to thwart the aforementioned largely undefended side-channel attacks . \textsf{RCL} has been implemented in a superscalar processor and detailed evaluation results show that \textsf{RCL} incurs only small costs in area, frequency and execution time.

Inspection robots are popularized in substations due to the lack of personnel for operation and maintenance. However, these inspection robots remain at the level of perceptual intelligence, rather than cognition intelligence. To enable a robot to automatically detect defects of power equipment, object recognition is a critical step because criteria of infrared diagnosis vary with types of equipment. Since this task is not a big‐sample learning problem, prior knowledge needs to be added to improve existing methods. Here, an object recognition model based on human‐level concept learning is proposed, which utilizes relationship between equipment. The proposed method is composed of three parts: Mask RCNN, Bayesian Context Network and human‐level concept learning. As the backbone network, Mask RCNN, a pixel‐wise segmentation network, gives preliminary recognition results. Then, based on the object relationship graph of Bayesian Context Network, human‐level concept learning corrects the results in sequence by maximizing the conditional probability of an object given its neighbourhood. Experiments show that the accuracy of the proposed method increases 9.7% compared with its backbone network, making industrial application of this technology possible.

Background Sterilization of milk is aimed at killing the microorganisms present. There are three main sterilization methods commonly used in milk processing: high temperature and short time (HTST) pasteurization, ultrahigh pasteurization (UP), and ultrahigh temperature (UHT) sterilization. The Maillard reaction is of special interest in studying the effect of heat treatment on milk quality. Furfural compounds are one of the typical intermediates of the Maillard reaction, which have safety risks related to mutagenic and genotoxic effects. The furfural compounds content is directly related to the heat treatment intensity. Results The furfural compounds content was measured using high-performance liquid chromatography with ultraviolet detection in 12 min. Then, 13 levels of heat treatment intensity (combinations of temperature and time) and three levels of homogenization pressure were selected to study the change of the furfural compounds content after different processing technologies in a pilot plant. The results show a higher temperature treatment can stimulate more Maillard reaction intermediates, such as hydroxymethylfurfural and furfural. A temperature regression evaluation model and content prediction models of hydroxymethylfurfural and furfural were developed to quantify the relationship between the furfural content and heat treatment with the data from the pilot plant. Conclusion Based on the temperature evaluation model, the heating temperature of three milk products was evaluated. The homogenization pressures had little effect on the furfural content in liquid milk. The emergence of the furyl methyl ketone and methylfurfural can be detected after overprocessing of the liquid milk. © 2020 Society of Chemical Industry.

Supplemental material, sj-docx-1-eae-10.1177_0958305X221133263 for Hydrocarbon regulation and lower temperature pyrolysis of balikun oil shale kerogen by Fei Liu, Weiguang Shi, Tianbao Liu, Wei Li, Liang Sun, Xiangbin Liu, Changming Zhao, Benxian Li, Sunhua Deng, Zhaohui Dong, Chengwu Xu, Xiaofei Fu and Xiuling Yan in Energy & Environment

Supplemental material, sj-docx-1-eae-10.1177_0958305X221133263 for Hydrocarbon regulation and lower temperature pyrolysis of balikun oil shale kerogen by Fei Liu, Weiguang Shi, Tianbao Liu, Wei Li, Liang Sun, Xiangbin Liu, Changming Zhao, Benxian Li, Sunhua Deng, Zhaohui Dong, Chengwu Xu, Xiaofei Fu and Xiuling Yan in Energy & Environment

Supplemental material, sj-docx-1-cll-10.1177_09636897221086971 for Nonfreezing Low Temperature Maintains the Viability of Menstrual Blood–Derived Endometrial Stem Cells Under Oxygen–Glucose Deprivation Through the Sustained Release of Autophagy-Produced Energy by Tongtong Chen, Shenghui Zhang, Hongzhang Jin, Xiaofei Fu, Lingrui Shang, Yilin Lu, Yuliang Sun, Badrul Hisham Yahaya, Yanli Liu and Juntang Lin in Cell Transplantation

In this work, particles of activated carbon supported by Fe-N-TiO2 (Fe-N-TiO2/AC) were synthesized and used as the three-dimensional (3D) particle electrode for folic acid wastewater treatment in the 3D electrolysis and photocatalysis coupling process. The structure, morphology, and physical and electrochemical properties of the Fe-N-TiO2/AC particles were characterized, and the results showed that Fe-N-TiO2 was bound on the surface of AC particles by chemical attachment, and the Fe-N-TiO2/AC particles had better capability of adsorption and charge transfer as compared with the TiO2/AC particles. The effects of key operating parameters in the reaction process, including the current density (optimum 0.6 mA/cm2), aeration (optimum 5 L/min), pH value (optimum 5) and the ratio of Fe-N-TiO2/AC particles to cellulose acetate film coating AC particles (optimum 4:1), were optimized regarding the total oxygen carbon (TOC) removal. Under the optimum conditions, TOC removal from folic acid wastewater reached 82.4% during 120 min photoelectrocatalysis. The kinetic analysis and mechanism study showed that the degradation process fitted to the second-order kinetic model better than to the first-order, and the system exhibited synergistic effects in inhibiting photogenic electron–hole recombination and improving electrolytic efficiency. At the same time, this system has the ability to overcome the interference of the strong ionic strength in folic acid wastewater.

A quantitative predictive method was established by utilizing fault throw–distance curve, average throw gradient, and structural amplitude variation gradient, combined with data of water cut and da...

Image fusion has become an active and promising research topic in image processing. It provides an effective way to combine several source images to form a composite image with more detailed information than any one of the source images. An FDST-PCNN framework, which integrates finite discrete shearlet transform (FDST) with pulse-coupled neural network (PCNN), is proposed to possess a higher ability enhance fusion effects. We first propose a structure-based saliency (SBS) map to enhance the clear and important features in one image. The SBS map combines the depth information with the saliency information and could be a good representation of the most essential information of the source images. After multi-scale decomposition by the FDST, the SBS map of the source images and the modified-spatial-frequency of the subbands are both utilized to tune the PCNN neuron response and determine the fused coefficients in each subband. The experimental results on multi-focus and multi-sensor images verify the effectiveness of our proposed fusion method. Compared with other PCNN-based fusion methods, the proposed method achieves significant improvement in preserving detailed edge information and improving overall visual performance.

A novel environmental decalcifying agent was prepared with allylpolyethoxy amino carboxylate (APEAA), hydroxyethyl acrylate (HEA), and maleic anhydride (MA) by means of free-radical polymerization in an aqueous solution. The morphology and structure of the samples were characterized through scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectrometry, and 1H nuclear magnetic resonance (1H NMR) spectra. The molecular-weight distribution of APEAA–HEA–MA was determined by the gel permeation chromatography method. APEAA–HEA–MA was used as a green decalcifying agent to remove calcium from crude petroleum, and the impact of factors such as monomer ratio, copolymerization time, dosages, and desalination temperature was analyzed. It is found that the decalcification rate of APEAA–HEA–MA could reach to its maximum, and the calcium removal efficiency was approximately 97.88% when the monomer molar ratio of APEAA–HEA–MA was 1:2:5, the reaction time of copolymerization was 2 h, the dosage was 100 ppm, and the desalination temperature was 100 °C. This research work can promote the exploration on facile synthesis of a novel terpolymer and its potential application in refinery desalting processes.

Novel Cu1.96S/g-C3N4 0D/2D p-n heterojunctions were successfully synthesized via a facile one-step calcination approach using thiocarbamide as both precursor and sulfur source. The Cu1.96S nanoparticles with sizes of 3–10 nm were closely anchored on the surface of g-C3N4 with good dispersion and the Cu1.96S/g-C3N4 nanocomposites were used as a photocatalyst for photodegradation of ciprofloxacin (CIP) under visible light. The experimental results demonstrated that the visible light photocatalytic activity of the Cu1.96S/g-C3N4 0D/2D p-n heterojunction was significantly enhanced in comparison with pure g-C3N4 and the degradation rate was up to about 3.2 times that of pure g-C3N4. The increased photocatalytic activity of the Cu1.96S/g-C3N4 nanocomposites could be attributed to the formation of the heterojunctions between g-C3N4 and Cu1.96S, which were conducive to avert the aggregation of small Cu1.96S nanoparticles and suppresses the recombination of photoinduced charge. Moreover, the Cu1.96S/g-C3N4 photocatalyst exhibited high stability for CIP degradation even after seven successive cycles.

Potential furfural compounds were detected by reverse phase high performance liquid chromatography (HPLC)-diode array detector (DAD) in milk-based formula (MBF), ultra-high temperature milk (UHT) and pasteurised yoghurt (PY). The content of potential 5-hydroxylmethyl-2-furaldehyde (HMF) and 2-furaldehyde (F) are significantly different in MBF, UHT and PY. 2-Furyl methyl ketone (FMC) and 5-methyl-2-furaldehyde (MF) were not detected in MBF, UHT and PY. Stress testing selected high temperature and high humidity to study the evolution of furfural compounds in MBF, UHT and PY. The contents of potential HMF and F sharply increased under high temperature conditions, while they showed little change under high humidity conditions. Accelerated testing and long-term testing were also conducted. Finally, regression equations of temperature–time-furfural content relationships were derived, by which the contents of furfural compounds in these dairy products stored under certain conditions for a certain time could be predicted.

Mesoporous ceramic functional nanomaterials (MCFN) is a self-assembled environmental adsorbent with a monolayer molecular which is widely used in the treatment of industrial wastewater and contaminated soil. This work aimed to study the relationship between the adsorption behaviour of Cd(II) by MCFN and contact time, initial concentration, MCFN dosage, pH, oscillation rate and temperature through a batch adsorption method. The adsorption kinetic and isotherm behaviours were well described by the pseudo-second-order and Langmuir models. The batch characterization technique revealed that MCFN had several oxygen-containing functional groups. Using Langmuir model, the maximum adsorption capacity of MCFN for Cd(II) was 97.09 mg g−1at pH 6, 25°C, dosage of 0.2 g and contact time of 180 min. Thermodynamic study indicated that the present adsorption process was feasible, spontaneous and exothermic at the temperature range of 25–55°C. The results of this study provide an important enlightenment for Cd removal or preconcentration of porous ceramic nanomaterial adsorbents for environmental applications.

Predictions of fault reactivation and the hydraulic seal of cap rock are integral parts of the seal integrity research programme of the Banzhongbei gas storage facility (BGS) to ensure the safe storage of natural gas in subsurface reservoirs. We attempt to combine the heterogeneity of geomechanical properties, including frictional coefficient and cohesive strength, into a workflow to estimate fault reactivation risk and the maximum sustainable fluid pressure that will not induce failure of trap-bounding faults and cap rock. Based on the Griffith – Coulomb Failure criterion, fault failure modes – including tensile failure, shear failure and hybrid failure – may occur under conditions of the same in situ stress field as a result of the strength heterogeneity of fault rocks, which plays a key role in the estimation of integrity of the entire fault trap. The juxtaposition of the seal on the BQ Fault with high shale gouge ratio (SGR) values makes a significant contribution to the high fluid pressure build-ups during gas injection, and its low strength properties lead to a higher reactivation risk for the Banqiao (BQ) Fault than for the B816 Fault. The increased pore-fluid pressure adjacent to the BQ Fault induced by gas injection should be lower than 9.7 MPa in order to avoid failure. Furthermore, the maximum sustainable fluid pressure of the cap rock is approximately 13.9 MPa at the locations of the injection wells.

Most major oil zones in the Daqing Oilfield have reached a later, high water cut stage, but oil recovery is still only approximately 35 %, and 50 % of reserves remain to be recovered. The remaining oil is primarily distributed at the edge of faults, in poor sand bodies, and in insufficiently injected and produced areas. Therefore, the edge of faults is a major target for remaining oil enrichment and potential tapping. Based on the dynamic change of production from development wells determined by the injection–recovery relationship at the edge of faults, we analyzed the control of structural features of faults on remaining oil enrichment at the edge. Our results show that the macroscopic structural features and their geometric relationship with sand bodies controlled remaining oil enrichment zones like the edges of NNE-striking faults, the footwalls of antithetic faults, the hard linkage segments (two faults had linked together with each other to form a bigger through-going fault), the tips of faults, and the oblique anticlines of soft linkages. Fault edges formed two types of forward micro-amplitude structures: (1) the tilted uplift of footwalls controlled by inverse fault sections and (2) the hanging-wall horizontal anticlines controlled by synthetic fault points. The remaining oil distribution was controlled by micro-amplitude structures. Consequently, such zones as the tilted uplift of the footwall of the NNW-striking antithetic faults with a fault throw larger than 40 m, the hard linkage segments, the tips of faults, and the oblique anticlines of soft linkage were favorable for tapping the remaining oil potential. Multi-target directional drilling was used for remaining oil development at fault edges. Reasonable fault spacing was determined on the basis of fault combinations and width of the shattered zone. Well core and log data revealed that the width of the shattered zone on the side of the fault core was less than 15 m in general; therefore, the distance from a fault to the development target should be larger than 15 m. Vertically segmented growth faults should take the separation of the lateral overlap of faults into account. Therefore, the safe distance of remaining oil well deployment at the fault edge should be larger than the sum of the width of shattered zone in faults and the separation of growth faults by vertical segmentation.

The world’s rapid economic growth has contributed to the ever increasing demand for energy which results in the increase of fossil fuels usage. On the other hand, renewable energies, which are considered environmentally friendly, cannot replace the fossil fuels in the short term. For this, CO2 capture and storage (CCS) technologies could work as transitional technology. To ensure a meaningful underground storage, well integrity is potentially the greatest challenge. On one hand, the injected CO2 may cause severe corrosion to metallic tubulars and cement in the wellbore. Identification, quantification and mitigation of this corrosion are the key to achieve satisfactory well conditions. On the other hand, the mechanical integrity loss due to cyclic and thermal loading in the well life will also occur, so to investigate and evaluate well integrity is of paramount importance to ensure a safe operation and storage. This paper presents a definition of well integrity in the scope of CSEGR as well as the mechanisms of well integrity loss. Overview on corrosion issues of metallic and cement corrosion along with the remedial measures is discussed. Through a thorough literature review, well integrity criteria for new and old wells are introduced to provide a guidance for material selection for the usage in CSEGR. Moreover, in order to evaluate the integrity of operational and abandoned wells, this paper provides a review on the existing monitoring methods, as well as risk based methods such as FEPs analysis, Performance and Risk Management, CO2-PENS, and put forward a new concept of well integrity evaluation.

After the power distribution system (DS) fails, a single power supply recovery method will cause certain loads to fail to recover in time. To improve the reliability of distribution systems with distributed generation, this paper proposes a two-stage network restoration reliability assessment method considering island division and network reconfiguration. In the process of network fault recovery, firstly, distributed generation is used to supply power to the load point of power loss, islanding of the network after fault with the aim of minimizing power loss. Then the residual network is reconstructed and optimized by considering the network loss and voltage quality. Finally, the improved ieee33 node network is simulated based on Monte Carlo simulation method. The results show that this method is superior and can realize real-time load transfer, reduce power loss, improve the reliability of DS and the economy of system operation, Considering the continuous change of the network structure, the running state of the system can be described more accurately.

A study of faults and their control of deep gas accumulations has been made on the basis of dividing fault systems in the Xujiaweizi area. The study indicates two sets of fault systems are developed vertically in the Xujiaweizi area, including a lower fault system and an upper fault system. Formed in the period of the Huoshiling Formation to Yingcheng Formation, the lower fault system consists of five fault systems including Xuxi strike-slip extensional fault system, NE-trending extensional fault system, near-EW-trending regulating fault system, Xuzhong strike-slip fault system and Xudong strike-slip fault system. Formed in the period of Qingshankou Formation to Yaojia Formation, the upper fault system was affected mainly by the boundary conditions of the lower fault system, and thus plenty of multi-directionally distributed dense fault zones were formed in the T2 reflection horizon. The Xuxi fault controlled the formation and distribution of Shahezi coal-measure source rocks, and Xuzhong and Xudong faults controlled the formation and distribution of volcanic reservoirs of Y1 Member and Y3 Member, respectively. In the forming period of the upper fault system, the Xuzhong fault was of successive strong activities and directly connected gas source rock reservoirs and volcanic reservoirs, so it is a strongly-charged direct gas source fault. The volcanic reservoir development zones of good physical properties that may be found near the Xuzhong fault are the favorable target zones for the next exploration of deep gas accumulations in Xujiaweizi area.

An improved photocatalytic microfiltration membrane was successfully prepared by the impregnation method with nitrogen-doped TiO2/graphene oxide (GO) (NTG). By utilizing the unique role of N and GO, the photocatalytic activity of the membrane in UV and sunlight was improved. Compared with the Polyvinylidene Fluoride (PVDF) microfiltration membrane which was modified by TiO2, N-TiO2 (NT) and TiO2-GO (TG), the NTG/PVDF membrane exhibited high photocatalytic efficiency and significantly improved photodegradation power to the methylene blue (MB) solution under ultraviolet light and sunlight, with the photocatalytic efficiency reaching 86.5% and 80.6%, respectively. Scanning electron microscopy (SEM), X-ray diffractometry (XRD) and Fourier transform infrared spectroscopy (FT-IR) were used to analyze the morphology, crystal structure and chemical bonds of the membrane surface. The hydrophilicity of the modified PVDF microfiltration membrane was significantly improved, the flux of the pure water membrane reached 1672 Lm&minus, 2h&minus, 1, the flux of the MB solution was also significantly improved due to photodegradation. Therefore, the nitrogen-doped titanium dioxide graphene oxide PVDF microfiltration membrane (NTG/PVDF membrane) has great development prospects in sustainable water treatment.

Reactive Oxygen Species (ROS) and Reactive Nitrogen Species (RNS) are highly reactive species which play crucial roles in many fundamental physiological processes including cellular signalling pathways. Over-production of these reactive species by various stimuli leads to cellular oxidative stress which is linked to various disease conditions. Therefore, the development of novel detection methods for ROS and RNS is of great interest and indispensable for monitoring the dynamic changes of ROS and RNS in cells and for elucidating their mechanisms of trafficking and connections to diseases. We have been recently developing various fluorescent sensors which can selectively detect metal ions, ROS or RNS species in live cells or animals. Our turn-on profluorescent sensors are capable of imaging oxidative stress promoted by metal and H2O2 (i.e. the Fenton Reaction conditions) in living cells (Chem Commun 2010); our highly selective and sensitive iron sensors can image the endogenous exchangeable iron pools and their dynamic changes with subcellular resolution in living neuronal cells (ChemBioChem 2012 and unpublished data), and so do our superoxide sensors (ChemBioChem 2012 and unpublished data). Moreover, we have recently developed nitric oxide (NO) sensors for molecular imaging of stimulated NO production in live cells with subcellular resolution as well as novel near infra red (NIR) sensors for NO imaging in live animals.