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Alarms generated by a wind turbine alarm system indicate the need for emergency action by operators to protect the turbine from running into risky conditions. However, it can be challenging for operators to identify the fault types that trigger alarms, particularly with few labeled fault samples. This paper proposes a novel fault diagnosis method for wind turbines with alarms that collaboratively uses labeled and unlabeled alarms to improve diagnosis accuracy. First, the proposed method distinguishes different alarm sequences using a designed Siamese convolutional neural network with an embedding layer (S-ECNN) model. Then, the fault category of an unknown alarm sequence is diagnosed based on similarity scores. Specifically, the Skip-gram model is used to mine potential relationships among alarms in unlabeled alarm sequences, and pretrained alarm vectors are obtained. In the S-ECNN model, the pretrained alarm vectors are further optimized and trained using labeled alarm sequences. The similarity scores are calculated based on the distance between the extracted discriminative features of alarm sequences. The effectiveness of the proposed method is validated using actual alarm data from a wind farm.

The transient tribological phenomenon and premature lubricant breakdown have been widely observed in metal forming, leading to excessive friction at the contact interfaces. In this research, the transient tribological behaviour of a two-phase lubricant were studied under complex loading conditions, featuring abrupt interfacial temperature, contact load, and sliding speed changes, thus representing the severe interfacial conditions observed in warm/hot metal forming applications. The strong experimental evidence indicates that the evolution of friction was attributed to the physical diminution and chemical decomposition effects. As such, a visco-mechanochemical interactive friction model was developed to accurately predict the transient tribological behaviour of the two-phase lubricant under complex loading conditions. The new friction model exhibited close agreements between the modelling and experimental results.

By using drilling, high-precision 3D seismic data, data of geochemistry, logging and testing, the reservoir characteristics and accumulation conditions of the KL6-1 lithologic oilfield in the Laibei Low Uplift in the Bohai Sea are examined comprehensively. The study shows that: KL6-1 oilfield is a monolithic, high-quality, large-scale Neogene lithologic oilfield featuring shallow reservoir depth, high productivity, concentrated oil-bearing intervals, large oil-bearing area, and high reserve abundance; hydrocarbon source supply from two directions provides a sufficient material basis for the formation of large oil field; two types of “inherited structural ridge” developed under the effect of block rotation, late active faults formed by Neotectonic movement, and widely distributed contiguous sand bodies provide an efficient oil and gas transportation system for the large-scale accumulation of oil and gas; contiguous channel and lacustrine lowstand system sand bodies developed in low accommodation condition provide the basic condition for the formation of large-scale lithologic traps; deep formations structural ridge, faults (dominant migration pathways) and large-scale superimposed contiguous sand bodies constitute a “vine type” oil and gas migration and accumulation system in the Laibei Low Uplift, which is conducive to the formation of large-scale and high-abundance lithologic reservoir in this area. The successful discovery of KL6-1, 100 million ton reserve order lithologic oil field, has revealed the exploration potential of Neogene large lithologic reservoirs in Bohai Sea, expanded the exploration field, and also has certain reference significance for the exploration of large lithologic reservoirs in similar areas.

While the chemistry of gold clusters has been developed rapidly, the knowledge of trinuclear gold clusters with low-valent gold remains scarce. Herein, we report the synthesis, structural characterization, and density functional theory (DFT) calculations of trinuclear anionic gold clusters 3a and 3b ligated by dialkylsilylene (1a) and dialkylgermylene (1b), respectively.

It has been considered as a great challenge to identify the blending ratio of polyester/cotton yarn in the field of textile industry. A new digital cross-sectional image processing method based on geometrical shape analysis is proposed to improve the measurement accuracy of polyester/cotton blend ratio. A self-developed microscope image capturing system is established to digitalise the cross-sectional images of polyester/cotton blended yarn. One set of image preprocessing algorithm is developed to conduct greyscale inversion, median filtering denoising and binarisation. The specially designed edge detection algorithm is used to identify the continuous profile of fibres. Finally, the roundness value of the cross-sectional fibre is calculated based on the proposed roundness algorithm, it can be used to identify the polyester/cotton fibres and calculate the blending ratio of them. Our experimental results show that the new digital analysis method proposed in this paper is feasible for the measurement of polyester/cotton blended ratio; therefore, it has a good application prospect in the field of textile quality control, including the development of new equipment, methods and standards.

A cyclic (R2 SnAu)3 anion (3- , R2 Sn=2,2,5,5-tetrakis(trimethylsilyl)-1-stannacyclopentane-1,1-diyl) has been synthesized as a stable blue salt with K+ (THF)6 through the reaction of stable dialkylstannylene 1 with R'3 PAuCl (R'=Et, Ph) followed by the reduction with KC8 . Crystallographic and NMR analysis shows that the six-membered (SnAu)3 ring of 3- is planar and highly symmetric with an equal distance of six Au-Sn bonds. A UV/Vis spectrum of 3- in hexane reveals an intense absorption maximum at 598 nm. While cyclic Au3 - with four valence electrons is known as unstable anti-aromatic anion, 3- with three divalent tin ligands is stable σ aromatic anion with an unprecedented Mobius orbital array as predicted by the perturbation MO and CCSD analysis of 3- .

Review A Review of Renewable Energy and Storage Technologies for Automotive Applications Xiangnan Yu 1, Yuhai Jin 1, Heli Liu 1, Arnav Rai 1, Michelle Kostin 1, Dimitrios Chantzis 1, Denis J. Politis 2, and Liliang Wang 1,* 1 Department of Mechanical Engineering, Imperial College London, London SW7 2AZ, UK 2 Department of Mechanical and Manufacturing Engineering, University of Cyprus, Nicosia, 1678, Cyprus * Correspondence: liliang.wang@imperial.ac.uk Received: 29 September 2022 Accepted: 9 November 2022 Published: 25 December 2022 Abstract: Transportation, as the backbone of the modern economy, continues to be a significant contributing factor to environmental pollution and poor air quality. Whilst numerous efforts have been made to address energy consumption and emissions through the manufacturing and end use stages, the use of fossil fuels continues to grow at an exponential rate. A key target area to assist with fuel consumption reduction targets is the implementation of renewable energy combined with energy storage technologies. The aim of this review is to investigate various means of production for renewable energy and energy storage technologies with the specific focus on the automotive industry.

Review Industry 4.0 in Metal Forming Industry Towards Automotive Applications: A Review Heli Liu 1,2, Saksham Dhawan 1,2, Merrill Shen 1, Kangan Chen 1, Vincent Wu 3, and Liliang Wang 1,2,* 1 Department of Mechanical Engineering, Imperial College London, London, SW7 2AZ, UK 2 SmartForming Research Base, Imperial College London, London, SW7 2AZ, UK 3 School of Informatics, The University of Edinburgh, Edinburgh, EH8 9LE, UK * Correspondence: liliang.wang@imperial.ac.uk Received: 23 September 2022 Accepted: 18 November 2022 Published: 18 December 2022 Abstract: Industry 4.0 is shaping the metal forming industry. The ongoing key Industry 4.0 technologies, including the industrial cyber-physical system (I-CPS), industrial internet of things (I-IoT), digital twin (DT), big data (BD) and cloud computing (CC), are expected to improve every stage during the metal forming processes, including the supply chains, raw material provision, tool design and manufacture, forming operations, energy consumption, cost, quality control and customer services. Here, we review the development and implementations of these key Industry 4.0 technologies in the metal forming industry. Based on the discussion of the opportunities and challenges of Industry 4.0 technologies in metal forming, this review provides some perspectives of future metal forming research directions towards automotive applications.

Tunneling magnetoresistive (TMR) sensors have broad application prospects because of their high sensitivity and small volume. However, the inherent hysteresis characteristics of TMR affect its applications in high accuracy scenarios. It is essential to build a model to describe the attributes of hysteresis of TMR accurately. Preisach model is one of the popular models to describe the behavior of inherent hysteresis for TMR, whereas it presents low accuracy in high-order hysteresis reversal curves. Furthermore, the traditional Preisach model has strict congruence constraints, and the amount of data seriously affects the accuracy. This paper proposes a hysteresis model from a probability perspective. This model has the same computational complexity as the classic Preisach model while presenting higher accuracy, especially in high-order hysteresis reversal curves. When measuring a small amount of data, the error of this method is significantly reduced compared with the classical Preisach model. Besides, the proposed model’s congruence in this paper only needs equal vertical chords.

Digoldgermanes with a gold coordinated by a dialkylgermylene ligand, R’2Ge(AuPR3)(AuGeR’2) (3a; R = Me, 3b; R = Et), were synthesized as green solids through the reactions of stable dialkylgermylene 1 with R3PAuCl followed by the reduction with KC8 at ambient temperatures. The structural characteristics of 3a and 3b were elucidated using NMR spectroscopy, X-ray crystallography, and DFT calculations. An intense absorption maximum was observed at 590 nm in the UV-vis spectrum of 3a in hexane. A pendular motion of AuPR3 group between Ge(IV) and Ge(II) of 3a and 3b occurring in the NMR time scale was found by the dynamic 1H NMR analysis, suggesting that the Ge(II) ligand has an enhanced electrophilicity to be attacked by the nucleophilic gold atom which closes to ‒1 oxidation state. DFT calculations of 3a revealed the existence of high-lying σ(Ge-Au) type HOMO and low-lying LUMO with germylene pπ nature. We show the bond formation and activation alternatively at Au or Ge atom, a methylation of digoldgermane 3a with MeOTf affords methylgermane 5. Moreover, the digoldgermane 3a reacts with Cl− ion of Ph4PCl and CH3C(O)Cl smoothly to form the corresponding chloride-addition product 7 and chlorogoldgermane 9, respectively. Cyclic trimerization reactions of aromatic isocyanates were high-efficiently catalyzed by 3a giving the corresponding 1,3,5-triaryl isocyanurates.

The bonding between gold and main-group metallic elements (M) featuring Auδ−−Mδ+ polarity, has been studied recently. The gold in the bonds is expected to have the oxidation number of −1, and hence, nucleophilic. However, the knowledge of the reactivity of the gold-metal bonds remains limited. Here, we report digold-substituted germanes of the form of R’2Ge(AuPR3)(AuGeR’2) (3a; R = Me, 3b; R = Et), featuring two Au-Ge(IV) and one Au-Ge(II) bonds. DFT calculations of 3a revealed the existence of high-lying σ(Ge-Au) type HOMO and low-lying LUMO with germylene pπ nature. A pendular motion of AuPR3 group between Ge(IV) and Ge(II) of 3 occurs in the NMR time scale, suggesting that the Ge(II) center has an enhanced electrophilicity to be attacked by the nucleophilic gold (−I) atom. 3a reacts with nucleophilic Cl− and electrophilic MeOTf reagents at Ge(II) and Ge(IV) centers, respectively.

Fluoro(dialkyl)stannylenoid 2 exhibits unique reactivity towards ethynes with acetylenic hydrogen and those with trimethylsilyl groups, though the corresponding free dialkylstannylene 1 is inactive against those ethynes. Stannylenoid 2 reacts smoothly with gaseous ethyne and phenylethyne at room temperature, giving the corresponding diethynylstannanes, di(phenylethynyl)stannane 3 and diethynylstannane 6, respectively, in good yields with the concomitant evolution of H2. Trimethylsilyl-substituted ethynes such as 1-trimethylsilyl-(2-phenyl)ethyne and 1,2-bis(trimethylsilyl)ethyne react similarly to give 3 and bis(trimethylsilylethynyl)stannane 8, respectively. Rather unexpectedly, the reaction of 2 with (trimethylsilyl)ethyne affords 1,2-bis(ethenylstannyl)ethyne 7 in a good yield. The reactions of 2 with methyl and ethyl propynoates give the same products 4 and 5 as those obtained during the reaction of dialkylstannylene 1 without CsF. Pathways involving the nucleophilic attack of cesium acetylide to an ethyne-complexed stannylene were proposed, while the detailed mechanisms remain unknown. The structure of 7 was studied by single crystal X-ray diffraction analysis.

This paper discusses adaptive synchronization control for complex networks interacted in an undirected weighted graph, and aims to provide a novel and general approach for the design of distributed update laws for adaptively adjusting coupling weights. The proposed updating laws are very general in the sense that they encompass most weight update laws reported in the literature as special cases, and also provide new insights in the analysis of network system evolution and graph weight convergence. We show a rigorous proof for the synchronization stability of the overall complex network to a synchronized state, and demonstrate the convergence of adaptive weights for each edge to some bounded constants. A detailed comparison with available results is provided to elaborate the new features and advantages of the proposed adaptive strategies as compared with conventional adaptive laws. The effectiveness of the proposed approach is also validated by several typical simulations.

The interfacial heat transfer coefficient (IHTC) is an essential parameter in hot stamping for determining the optimal process parameters necessary to achieve the critical cooling rate and thus the desired post-form strength in a formed component. Aluminium chromium nitride, chromium nitride and titanium nitride are currently being widely studied in the hot stamping industry as tool coatings due to their excellent wear performance, although their effects on the IHTC have yet to be determined. In practical hot stamping processes, the contact pressure may also change over extremely short periods of time, leading to abrupt changes in the IHTC and consequently the temperature evolutions of the workpiece. These abrupt changes in contact pressure and their effects on the IHTC have yet to be studied either. In this paper, to address those challenges, the IHTCs between an AA7075 aluminium alloy and different coated tools with a 3-stage evolutionary variable contact pressure were quantitatively determined, and a mechanism-based model developed to accurately predict their values.

A borane B(C6 F5 )3 -catalyzed metathesis reaction between the Si-C bond in the cyclic (alkyl)(amino)germylene (CAAGe) 1 and the Si-H bond in a silane (R3 SiH; 2) is reported. Mechanistic studies propose that the initial step of the reaction involves Si-H bond activation to furnish an ionic species [1-SiR3 ]+ [HB(C6 F5 )3 ]- , from which [Me3 Si]+ [HB(C6 F5 )3 ]- and an azagermole intermediate are generated. The former yields Me3 SiH concomitant with the regeneration of B(C6 F5 )3 whereas the latter undergoes isomerization to afford CAAGes bearing various silyl groups on the carbon atom next to the germylene center. This strategy allows the straightforward synthesis of eight new CAAGes starting from 1. Ministry of Education (MOE) Nanyang Technological University Accepted version We are grateful to the Nanyang Technological University (NTU) and Ministry of Education, Singapore (MOE2015-T1-001-029:RG9/15) for financial support. We also like to thank Dr. Li Yongxin (NTU) for assistance in X-ray crystallographic analysis.

FAST (Fast light Alloys Stamping Technology) has recently been developed to efficiently and economically manufacture lightweight, high strength structural components from aluminium alloys sheet. Post-form strength prediction of 6xxx series aluminium alloy (AA6xxx) after FAST and multiple stage heat treatments has been a challenge. This is due to the effect of pre-existing dislocations induced via high temperature plastic deformation in the forming process. In the present research, a new PFS (post-form strength) model has been proposed to predict the age-hardening response of AA6xxx alloys undergoing FAST and subsequent thermal cycles. The model incorporates two sub-models, for simulating viscoplastic flow and predicting strength evolution respectively. The first sub-model incorporates a set of constitutive equations, developed to model the stress-strain curve of AA6xxx during FAST. The second sub-model employs precipitation-hardening and dislocation-hardening theories to simulate the evolution of microstructure and, as a consequence, strength of alloys undergoing artificial ageing cycles. This is calculated by considering the intrinsic resistance of the alloy to dislocation movement due to solute atoms and precipitates. The strength was computed accurately via the internal state variables method, in which dislocation density, volume fraction of precipitates, solute concentration and radii of precipitates were correlated. Furthermore, the model was validated by comparing results with transmission electron microscope (TEM) images as well as hardness measurements. Hence, the model performs as a powerful and comprehensive tool to simulate post-form strength of 6xxx series aluminium alloys that undergo complicated thermomechanical processes including high temperature deformation and post-form heat treatment, with less than 5% deviation between measured and predicted values.

The galling process remains one of the least understood phenomena in metal forming. The transfer of material from a work-piece onto the tool surface can cause an evolutionary increase in friction coefficient (COF) and thus the use of a constant COF in finite element (FE) simulations leads to progressively inaccurate results. For an aluminium work-piece, material transfer, which has history and pressure dependency, is determined by a dynamic balance between the generation and ejection of wear particles acting as a ‘third body’ abrasive element at the contact interface. To address this dynamic interactive phenomenon, pin-on-disc tests between AA6082 and G3500 were performed under step load change conditions. The COF evolutions, morphologies of the transfer layer and its cross-section were studied. It has been found that contact load change will disequilibrate and rebuild the dynamic balance and high load will increase the generation and ejection rate of third body and vice versa. Moreover, based on the experimental results, an interactive model was developed and presented to simulate the dynamic formation process of the aluminium third body layer under load change conditions, enabling multi-cycle simulations to model the galling distribution and friction variation.

The lubricant behaviour at elevated temperatures was investigated by conducting pin-on-disc tests between P20 tool steel and AA7075 aluminium alloy. The effects of temperature, initial lubricant volume, contact pressure and sliding speed on the lubricant behaviour (i.e. evolutions of the coefficient of friction (COF) and the breakdown phenomenon) were experimentally studied. The evolutions of COF at elevated temperatures consisted of three distinct stages with different friction mechanisms. The first stage (stage I) occurred with low friction when the boundary lubrication was present. The second stage (stage II) was the transition process in which the COF rapidly increased as the lubricant film thickness decreased to a critical value. In the final plateau stage (stage III), lubricant breakdown occurred and intimate contact at the interface led to high friction values. At the low friction stage (stage I), the value of COF increased with increasing temperature. The increase in temperature, contact pressure and sliding speed as well as the decrease in initial lubricant volume accelerated the lubricant breakdown.

The lubricant behaviours under varying contact conditions were investigated by conducting pin-on-strip tests between P20 tool steel and AA7075 aluminium alloy using an automated testing system, Tribo-Mate. The effects of temperature changes, and rapid load and speed changes on the coefficient of friction (COF) and lubricant breakdown phenomenon were experimentally studied. The evolutions of COF showed three distinct stages, indicating the transformation from boundary lubrication condition to dry sliding condition. The value of COF at the initial stage was found to increase with increasing temperature. The increase of temperature, contact load and sliding speed caused an earlier breakdown of the lubricant. An interactive friction model was developed to predict friction evolutions at varying contact conditions. A close agreement with errors less than 6.8% were achieved between the model predictions and experimental results.

Background Manure application and sewage irrigation release many intestinal pathogens into the soil. After being introduced into the soil matrix, pathogens are commonly found to attach to soil minerals. Although the survival of mineral-associated Escherichia coli O157:H7 has been studied, a comprehensive understanding of the attachment process and physiological properties after attachment is still lacking. Results In this study, planktonic and attached Escherichia coli O157:H7 cells on quartz were investigated using RNA sequencing (RNA-seq) and the isobaric tagging for relative and absolute quantitation (iTRAQ) proteomic method. Based on the transcriptomic and proteomic analyses and gene knockouts, functional two-component system pathways were required for efficient attachment; chemotaxis and the Rcs system were identified to play determinant roles in E. coli O157:H7 attachment on quartz. After attachment, the pyruvate catabolic pathway shifted from the tricarboxylic acid (TCA) cycle toward the fermentative route. The survival rate of attached E. coli O157:H7 increased more than 10-fold under penicillin and vancomycin stress and doubled under alkaline pH and ferric iron stress. Conclusions These results contribute to the understanding of the roles of chemotaxis and the Rcs system in the attachment process of pathogens and indicate that the attachment of pathogens to minerals significantly elevates their resistance to antibiotics and environmental stress, which may pose a potential threat to public health.