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A NEURAL NETWORK FOR WELD PENETRATION cONTROL IN GAS TUNGSTEN ARc WELDING

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Acta Metallurgica Sinica(English Letters) 2006年第1期19卷 27-33页

作者： c.S. Wu j. Q. Gao Y.H. zhao Institute of Materials joining Shandong University Jinan 250061 China

Realizing of weld penetration control in gas tungsten arc welding requires establishment of a model describing the relationship between the front-side geometrical parameters of weld pool and the back-side weld width with sufficient accuracy. A neural network model is developed to attain this aim. Welding experiments are conducted to obtain the training data set （including 973 groups of geometrical parameters of the weld pool and back-side weld width） and the verifying data set （108 groups）. Two data sets are used for training and verifying the neural network, respectively. The testing results show that the model has sufficient accuracy and can meet the requirements of weld penetration control.

关键词： neural network weld penetration control back-side weld width,gas tungsten arc welding

Machine learning guided automatic recognition of crystal boundaries in bainitic/martensitic alloy and relationship between boundary types and ductile-to-brittle transition behavior

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journal of Materials Science & Technology 2021年第25期84卷 49-58页

作者： X.c.Li j.X.zhao j.H.cong R.D.K.Misra X.M.Wang X.L.Wang c.j.Shang collaborative Innovation center of Steel Technology University of Science and Technology BeijingBeijing 100083China Department of Metallurgical Materials and Biomedical EngineeringUniversity of Texas at El Paso500 W.University AvenueEl PasoTX 79968USA

Gradient boosting decision tree(GBDT)machine learning(ML)method was adopted for the first time to automatically recognize and conduct quantitative statistical analysis of boundaries in bainitic microstructure using electron back-scatter diffraction(EBSD)*** spite of lack of large sets of EBSD data,we were successful in achieving the desired accuracy and accomplishing the objective of recognizing the *** with a low model accuracy ofcharacteristic features,the accuracy of the model was significantly enhanced to about 88%when the Euler angle was converted to overall misorientation angle(OMA)and specific misorientation angle(SMA)and considered as important *** this model,the recall score of prior austenite grain(PAG)boundary was~93%,high angle packet boundary(OMA>40°)was~97%,and block boundary was~96%.The derived outcomes of ML were used to obtain insights into the ductile-to-brittle transition(DBTT)***,ML modeling approach suggested that DBTT was not determined by the density of high angle grain boundaries,but significantly influenced by the density of PAG and packet *** study underscores that ML has a great potential in detailed recognition of complex multi-hierarchical microstructure such as bainite and martensite and relates to material performance.

关键词： Machine learning Feature engineering Automatic recognition Lath structure crystallography

Maximizing biomass utilization: An integrated strategy for coproducing multiple chemicals

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journal of Energy chemistry 2025年第1期100卷 180-191页

作者： Byeongchan Ahn Sua jo jonggeol Na j.jay Liu Young-ju Kim Wangyun Won Department of chemical and Biological Engineering Korea University Department of chemical Engineering (Integrated process) Kyung Hee University Department of chemical Engineering and Materials Science Ewha Womans University Department of chemical Engineering Pukyong National University Resources Engineering Plant Research Department Korea Institute of Geoscience and Mineral Resources

Lignocellulosic biomass is one of the viable solutions to alleviate the global warming. However, the limited utilization of biomass majorly focused on cellulose and hemicellulose restricts the economic and environmental feasibilities. To cope with this issue, we proposed an integrated process of co-producing 1,6-hexanediol（1,6-HDO） with tetrahydrofuran and adipic acid from biomass, referred to as Strategy A. To compare the impacts of lignin upgrading and feedstock, Strategy B, which co-produces tetrahydrofuran alone, and Strategy c, which is the traditional route to produce 1,6-HDO from fossil fuels, were used. Heat networks are also designed to reduce operating costs and indirect carbon emissions due to energy consumption, saving 87% and 83% of the heat and cooling requirements, respectively, in Strategy A. The market competitiveness of Strategy A was evaluated by determining the minimum selling price through techno-economic analysis, and sustainability was thoroughly investigated by quantifying the environmental impacts through both midpoint and endpoint life-cycle assessments（LcAs）.Strategy A was found to be the most favorable both economically（USRDScHARDOLLAR3,402/ton） and environmentally（-26.9 kg cO2eq.）. This indicates that lignin valorization is not only economically but also environmentally preferred. Finally, changes in economic and environmental feasibilities depending on economic, process, and environmental parameters were investigated using sensitivity and uncertainty analyses. The results of these analyses provide valuable insight into bio-based chemical production.

关键词： carbon capture and utilization

THEORETIcAL STUDY OF GIANT MAGNETO-IMPEDANcE IN AMORPHOUS FILMS WITH LONGITUDINAL MAGNETIc ANISOTROPY

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Acta Metallurgica Sinica(English Letters) 2000年第4期13卷 995-1000页

作者： Yu, j.Q. Zhou, Y. cai, B.c. zhao, X.L. Shanghai jiaotong Univ Shanghai China

Giant magneto-impedance (MI) effect in thin films with longitudinal magnetic anisotropy was studied theoretically. The effective permeability of films as a function of external magnetic field Ha, anisotropy field and other parameters of films was presented by Landau-Lifshitz-Gilbert theory. The theoretical results agree well with the experimental data, which shows a strong dependence of the impedance on the applied magnetic field.

关键词： Electric currents Magnetic anisotropy Magnetic fields Skin effect

IMPROVING THE SURFAcE PROPERTY OF Tc4 ALLOY BY LASER NITRIDING AND ITS MEcHANISM

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Acta Metallurgica Sinica(English Letters) 2006年第2期19卷 151-156页

作者： Y.L. Yang G.j. zhao D. Zhang c.S. Liu Gollege of Sdence Northeastern University Shenyang 110004 Ghina college of Material and Metallurgy Northeastern University Shenya g 110004 China

The mixing technology of laser and heated nitrogen was applied to improve the surface hardness of titanium alloy （ Tc4 ）. The samples were nitrided with laser power density of 6.S × 10^6SW. cm^-2, the scanning speed varioas from 100 to 500mm ·min^-1. The nitrogen gas was pre-heated to 300℃ to accelerate the nitriding process. Some interested samples were tested with XRD method （X-ray diffraction） to analyze the composition of nitrides, and the surface hardness of HV was measured. The results show that TiN and Ti2N were formed on the surface of Ti alloy with proper nitriding parameters, but TiN is the main composition. The surface hardness increased by three times, which is from the original value of 269to 794kg·mm^-2. The mechanism of the mixing technology is considered mainly of the activation of nitrogen by laser power and the pre-heated process which accelerated the nitriding process. The nitridation process can be considered as six steps given in detail. The result by analyzing the mechanism of improving the surface property of TiAl alloy shows the improvement of surface property due to two factors： the first reason is the result of laser annealing, and the second one is the formation of TiN.

关键词： laser nitridation surface property Ti alloy

INVESTIGATION OF THE LOW-cYcLE FATIGUE AND FATIGUE cRAcK GROWTH BEHAVIORS OF P91 BASE METAL AND WELD jOINTS

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Acta Metallurgica Sinica(English Letters) 2004年第4期17卷 597-600页

作者： H.c.Yang Y.Tu M.M.Yu j.zhao Dongfang Boiler (Group) Ltd Zigong 643001 ChinaDongfang Boiler (Group) Ltd Zigong 643001 ChinaDongfang Boiler (Group) Ltd Zigong 643001 ChinaDepartment of Materials Engineering Dalian University of Technology Dalian 116023 China

Low cycle fatigue tests and crack growth propagations tests on P91 pipe base metal and its weld joints were conducted at three different temperatures: room temperature, 550℃ and 575℃. The strain-life was analyzed, and the changes in fatigue life behavior and fatigue growth rates with increasing temperature were discussed. The different properties of the base metal and its weld joint have been analyzed.

关键词： P91 pipe low-cycle fatigue fatigue crack growth

Leveraging the potential of big genomic and phenotypic data for genome-wide association mapping in wheat

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The crop journal 2024年第3期12卷 803-813页

作者： Moritz Lell Yusheng zhao jochen c.Reif Leibniz Institute of Plant Genetics and crop Plant Research(IPK) Corrensstraße 3D-06466 SeelandGermany

Genome-wide association mapping studies(GWAS)based on Big Data are a potential approach to improve marker-assisted selection in plant *** number of available phenotypic and genomic data sets in which medium-sized populations of several hundred individuals have been studied is rapidly *** these data and using them in GWAS could increase both the power of QTL discovery and the accuracy of estimation of underlying genetic effects,but is hindered by data heterogeneity and lack of *** this study,we used genomic and phenotypic data sets,focusing on central European winter wheat populations evaluated for heading *** explored strategies for integrating these data and subsequently the resulting potential for *** interoperability between data sets was greatly aided by some overlapping genotypes and a linear relationship between the different phenotyping protocols,resulting in high quality integrated phenotypic *** this context,genomic prediction proved to be a suitable tool to study relevance of interactions between genotypes and experimental series,which was low in our *** to expectations,fewer associations between markers and traits were found in the larger combined data than in the individual experimental ***,the predictive power based on the marker-trait associations of the integrated data set was higher across data ***,the results show that the integration of medium-sized to Big Data is an approach to increase the power to detect QTL in *** results encourage further efforts to standardize and share data in the plant breeding community.

关键词： Big Data Genome-wide association study Data integration Genomic prediction Wheat

Impact of carbon-based nutrient enhancement on biofiltration performance for drinking water treatment

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journal of Environmental Sciences 2019年第8期31卷 124-131页

作者： Yu zhao Liz Taylor-Edmonds Robert c.Andrews Department of civil and Mineral Engineering University of Toronto

Incorporation of a carbon-based nutrient enhancementstrategy for drinking water biofiltration is an attractive option, especially for source waters which contain recalcitrant organics. This study compared biofilters that were operated in parallel and individually enhanced with amino acids(including alanine, phenylalanine, and tryptophan), inulin, and sucrose to increase biomass concentration and promote biodegradation of dissolved organic carbon(DOc) in the source water, including disinfection by-product(DBP) precursors. Biomass activity was characterized by measuring adenosine tri-phosphate(ATP), dissolved oxygen(DO) consumption, and through the use of laccase and esterase enzyme assays. Performance was evaluated in terms of headloss,turbidity, p H, DOc, UV254, and DBP formation potential(DBP FP). The introduction of carbonbased nutrients significantly increased biomass activity, where ATP values peaked at 976 ng/g of filter media, 853 ng/g, and 513 ng/g for amino acids, inulin, and sucrose-spiked biofilters,respectively, while a non-spiked control only reached 104 ng/g. DO utilization by the enhanced biofilters was significantly higher than the control, with a strong correlation between ATP and DO uptake observed for all filters(R^2> 0.74). Laccase and esterase enzyme activities of enhanced biofilters were also elevated(p > 0.05), suggesting greater biodegradation potential. Operational parameters such as headloss development and turbidity control were not impaired by carbon supplementation strategies or an increase in biomass concentration and activity. However, the enhancement strategy did not provide improvement in terms of source water carbon removal(DOc and UV254) or DBP FP when treated filters were compared to a control.

关键词： Biological filtration carbon enhancement Biomass Disinfection by-products Dissolved organic carbon

cadmium sulfide cage photocatalysis coupled electroactive biofilm for synergistic promotion of tetracycline degradation and electricity production

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journal of Materials Science & Technology 2023年第35期166卷 86-97页

作者： Z.S.Yuan j.X.Zou X.L.zhao j.Y.Shi c.S.Guo M.Yan School of chemistry and chemical Engineering Harbin Institute of TechnologyHarbin 150001China

Tetracycline(Tc)as a common broad-spectrum antibiotic,has been frequently detected in soil and sur-face *** becomes a great threat to the ecological ***,a device of photocatalysis as-sisted microbial fuel cell(photo-MFc)was constructed for Tc degradation and energy *** this photo-MFc,cadmium sulfide(cdS)cage photocatalysis can degrade most of Tc in a short *** the co_(3)O_(4)@c-cc(carbonization and calcination of the ZIF-67 precursor in-situ grown on the carbon cloth(cc))bioanode degrades the rest of Tc as well as the photocatalytic products,thus improving the *** co-existence of photocatalysis with bioanode changes the microbial community structure of the *** dominant phylum is Geobacter(60.2%)in normal MFc while that in photo-MFc are Pro-teobacteria(43.5%)and Geobacter(33.2%).Therefore,the synergistic effect of photocatalytic degradation and biodegradation achieves a chemical oxygen demand(cOD)removal of 98.6%,which is higher than that of normal MFc(77.6%)or single cdS cage photocatalysis(23.8%).In addition,the photogenerated electrons can be transferred to the cathode,which reduces their combination with holes and increases the electricity generation of MFc,achieving a maximum power density of 3.37 W/m^(2).After degradation,the effluent with 200 mg L^(−1) Tc exhibits no visible ***,electrochemical test,finite-difference time-domain(FDTD),density functional theory(DFT)calculation and the free radical trapping experiments verify the possible mechanisms of photocatalytic degradation in this *** strat-egy paves a new way for low energy consumption removal and energy recovery of organic pollutants.

关键词： Photo-MFc cdS cage Tetracycline degradation Mineralization Electricity production