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Automatic recognition and intelligent analysis of central shrinkage defects of continuous casting billets based on deep learning

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Journal of Iron and Steel Research(International) 2023年第5期30卷 937-948页

作者： Gong-hao Lian Qi-hao Sun Xiao-ming Liu Wei-miao Kong Ming Lv Jian-jun Qi Yong Liu Ben-ming Yuan Qiang Wang Key Laboratory of Electromagnetic Processing of Materials(Ministry of Education) Northeastern UniversityShenyang 110819LiaoningChina State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819LiaoningChina Shandong Iron and Steel Group Co. Ltd.Jinan 271105ShandongChina HBIS Material technology Research Institude Shijiazhuang 050023HebeiChina Special Steel Business Department of Shandong Steel Laiwu Branch Jinan 271105ShandongChina

The internal quality inspection of the continuous casting billets is very important,and mis-inspection will seriously affect the subsequent production *** UNet-VGG16 transfer learning model was used for semantic segmentation of the central shrinkage defects of the continuous casting *** automatic recognition accuracy of the central shrinkage defects of the continuous casting billets reaches more than *** use the minimum circumscribed rectangle to quantify the geometric dimensions such as length,width and area of the central shrinkage defects and use the threshold method to rate the central shrinkage defects of the continuous casting *** results show that all the testing images are rated correctly,and this method achieves the automatic recognition and intelligent analysis of the central shrinkage defects of the continuous casting billets.

关键词： Central shrinkage Deep learning Image segmentation Circumscribed rectangle Automatic recognition

Comparative study on microbial community in intermittently aerated sequencing batch reactors （SBR） and a traditional SBR treating digested piggery wastewater

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Frontiers of Environmental science & Engineering 2017年第3期11卷 97-106页

作者： Xiaolin Sheng Rui Liu Xiaoyan Song Lujun Chen Kawagishi Tomoki Zhejiang Provincial Key Laboratory of Water science and technology Department of Environment in Yangtze Delta Region Institute of Tsinghua University Zhejiang Jiaxing 314006 China School of Environment Tsinghua University Beijing 100084 China Aqua Development Center Mitsubishi Rayon Co. Ltd. Toyohashi 4408601 Japan

A traditional sequencing batch reactor （SBR） and two intermittently aerated sequencing batch reactors （IASBRs） were parallelly operated for treating digested piggery wastewater. Their microbial communities were analyzed, and the nitrogen removal performance was compared during the long term run. IASBRs demonstrated higher removal rates of total nitrogen （TN） and ammonium nitrogen （NH4＋ -N） than the SBR, and also demonstrated higher resistance against TN shock load. It was found that the more switch times between aerobic/anoxic in an IASBR, the higher the removal rates of TN and NH4＋ N. All the reactors were predominated by Thauera, Nitrosomonas and Nitrobacter, which were considered to be species of denitrifiers, ammonium oxidizing bacteria （AOB） and nitrite oxidizing bacteria （NOB）, respectively. However, the abundance and diversity was of great difference. Compared with SBR, IASBRs achieved higher abundance of denitrification related bacteria. IASBR 1# with four aerobic/anoxic switch times was detected with 25.63% of Thauera, higher than that in IASBR 2# with two aerobic/anoxic switch times （l 1.57% of Thauera）, and much higher than that in the SBR （only 6.19% of Thauera）. IASBR 2# had the highest percentage of AOB, while 1ASBR 1# had the lowest percentage. The denitrifiers abundance was significantly positive correlated with the TN removal rate. However, the NH4＋ N removal rate showed no significant correlation with the AOB abundance, but might relate to the AOB activity which was influenced by the average free ammonium （FA） concentration. Nitrobacter was the only NOB genus detectable in all reactors, and were less than 0.03%.

关键词： Digested piggery wastewater Intermittent aeration aeration Microbial community Partial nitrification^lenitrification processSequencing batch reactor (SBR)

Stable Li storage in micron-sized SiO_(x) particles with rigid-flexible coating

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Journal of Energy Chemistry 2022年第1期31卷 309-314,I0009页

作者： Ming-Yan Yan Zhu Liu Zhuo-Ya Lu Lin-Bo Huang Ke-Cheng Jiang Hong-Liang Li Sen Xin Quan Xu Yu-Guo Guo CAS Key Laboratory of Molecular Nanostructure and Nanotechnology CAS Research/Education Center for Excellence in Molecular SciencesBeijing National Laboratory for Molecular Sciences(BNLMS)Institute of ChemistryChinese Academy of Sciences(CAS)Beijing 100190China College of Materials science and Engineering State Key Laboratory of Biopolysaccharide Fiber Forming and Eco-TextileQingdao UniversityQingdao 266071ShandongChina Beijing IAmetal New Energy technology Co. LtdBeijing 100190China Dongguan TAFEL New Energy technology Co. LtdDonggiian 523000.GuangdongChina

Micrometre-sized electrode materials have distinct advantages for battery applications in terms of energy density,processability,safety and *** the silicon monoxide anode that undergoes electrochemical alloying reaction with Li,the Li(de)intercalation by micron-sized active particles usually accompanies with a large volume variation,which pulverizes the particle structure and leads to rapidly faded storage *** this work,we proposed to stabilize the electrochemistry *** of the micron-SiO_(x) anode by forming a rigid-flexible bi-layer coati ng on the particle *** coati ng consists of pyrolysis carbon as the inner layer and polydopamine as the outer *** the inner layer guarantees high structural rigidity at particle surface and provides efficient pathway for electron conduction,the outer layer shows high flexibility for maintaining the integrity of micrometre-sized particles against drastic volume variation,and together they facilitate formation of stable solid electrolyte interface on the SiO_(x) particles.A composite an ode prepared by mixing the coated micron-SiOx with graphite delivered improved Li storage performance,and promised a high-capacity,long-life LiFePO_(4)/SiO_(x)-graphite pouch *** strategy provides a general and feasible solution for building high-energy rechargeable batteries from micrometre-sized electrode materials with significant volume variation.

关键词： Lithium-ion batteries Anodes Micron-SiOx Rigid and flexible coating

Austenite grain growth of medium-carbon alloy steel with aluminum additions during heating process

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International Journal of Minerals,Metallurgy and Materials 2019年第3期26卷 282-290页

作者： Zi-yi Liu Yan-ping Bao Min Wang Xin Li Fan-zheng Zeng State key Laboratory of Advanced Metallurgy University of Science and Technology Beijing Xiangtan Iron & Steel Co. Ltd.of Hunan Valin

In this study, the effects of heating temperature(850–1100°C) and holding time(30–150 min) on the grain growth behavior of austenite in medium-carbon alloy steel were investigated by conducting experiments. The abnormal grain growth and mixed grain structure phenomenon are explained using an equilibrium precipitation phase diagram calculated by Thermo-Calc software package. The Al N particles were observed by field-emission scanning electron microscopy(FESEM), and the amount of AlN precipitations was detected by electron probe microanalysis(EPMA). Based on the research results, it was found that the average grain size of austenite in the test steel increased continuously with the increase of temperature and holding time. Furthermore, the abnormal growth of austenite occurred in the test steel at 950°C, and the heating temperature affected the austenite grain size more significantly. In addition, the decline in the amount of AlN second-phase particle in the test steel, which weakened the "pinning" effect on austenite grain boundaries, resulted in abnormal growth and the development of mixed austenite grain structures. The prediction model for describing the austenite grain growth of medium-carbon alloy steel during heating was established by regression analysis of the experimental data, and the model was verified to be highly accurate.

关键词： alloy steel austenite grain AlN growth model

Numerical and experimental research on different inlet configurations of high speed centrifugal compressor

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science China(Technological sciences) 2012年第1期55卷 174-181页

作者： LI Du YANG Ce ZHOU Mi ZHU ZhiFu WANG Hang School of Mechanical Engineering Beijing Institute of Technology Beijing 100081 China Basic Subject Department Bohai Shipbuilding Vocational College Huludao 125000 China Kangyue technology Co. Ltd. Shouguang 262711 China

Three different inlet configurations,including a original straight pipe and two bend pipes with different axial length,for a high speed low mass flow centrifugal compressor were modeled with whole blade passages and simulated unsteadily by 3D viscous Navier-Stokes *** performance disparities of compressor stage were tested and verified by experiments in which dynamic pressure data acquisition of internal flow field was *** the result shows,the choke point decreases to lower mass flow rate due to the distortion caused by bend-pipe inlet and is aggravated as the rotation speed *** distortion effect spreads circumferentially in impeller and makes the flow structure *** longer axial distance bent inlet leads to larger radial distortion and heavy blockage at mid-span under large mass flow mainly causes compressor choke margin *** pipe distortion brings an impact up to diffuser on unsteady pressure pulsation caused by blades sweep and the impact appears more powerful when it is closer to volute tongue.

关键词：离心的压缩机入口失真数字模拟动态数据获得

Experimental Investigation of Regular or Wavy Two-Phase Flow in a Manifold

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Fluid Dynamics & Materials Processing 2023年第1期19卷 37-50页

作者： Xiaowei Nie Lihui Ma Yiqiu Xu Dong Sun Weibo Zheng Liang Zhou Xiaodong Wang Xiaohan Zhang Weijia Dong Yunfei Li Sionpec Shengli Oilfield Company Dongying257000China Technical Inspection Center Sionpec Shengli Oilfield CompanyDongying257000China Offshore Oil Engineering Co. Ltd.Dongying257000China

An experimental study was conducted to investigate the properties of stratified regular or wavy two-phase flow in two parallel separators located after a manifold.A total of 103 experiments with various gas and liquid velocity combinations in three inlet pipes were conducted,including 77 groups of outlet pipe resistance symmetry and 26 groups of outlet pipe resistance asymmetry *** experimental results have revealed that when the gas-liquid flow rate is low,the degree of uneven splitting is high,and“extreme”conditions are *** the superficial gas velocity is greater than that established in the extreme case,the direction of the liquid-phase displacement is reversed,while that of the gas remains ***,the degree of gas phase bias tends to be mitigated with an increase in the gas velocity,while the uneven splitting degree of liquid approaches 10%.Finally,varying the gas-phase outlet pipe resistance is shown to effectively change the gas-liquid two-phase flow distribution.

关键词： Uneven phase distribution two-phase flow manifold asymmetric resistance

Optimization model coupling both chemical compositions and high-temperature characteristics of sintering materials for sintering burden

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International Journal of Minerals,Metallurgy and Materials 2014年第3期21卷 216-224页

作者： Ke-jiang Li Jian-liang Zhang Zheng-jian Liu Bu-xin Su Ling-tan Kong Tian-jun Yang School of Metallurgical and Ecological Engineering University of Science and Technology Beijing State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing

We developed a mathematical optimization model coupling chemical compositions and high-temperature characteristics of sintering materials, targeting the best quality and lowest cost. The simplex algorithm was adopted to solve this model. Four kinds of imported iron ores, two kinds of Chinese iron ore concentrates, and two kinds of fluxes were selected to verify both the model and the algorithm. The results confirmed the possibility of considering both chemical compositions and high-temperature characteristics of iron ores in the optimization model. This model provides a technical roadmap to obtain a precise mathematical correlation between the lowest cost and the grade of iron in sinters based on the condition of given raw materials, which can provide a reference to adjust the grade of iron in the sintering process for enterprise.

关键词： sintering burden optimization simplex algorithm chemical composition high temperature properies

Volatilization behaviour and volatilization kinetics of CaF2-Na2O-CaOSiO2-Al2O3-MgO-B2O3 synthetic mould flux

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Journal of Iron and Steel Research(International) 2019年第4期26卷 412-421页

作者： Ya-ru Cui Hao-yue Fan Zi-liang Guo Guo-hua Wang Xiao-ming Li Jun-xue Zhao Ze Yang School of Metallurgical Engineering Xi'an University of Architecture and TechnologyXi'an 710055ShaanxiChina Inner Mongolia Xinchuang Resources Recycling Co. Ltd.Ordos 014300Inner MongoliaChina

To reduce the volatilization of the volatile-containing slags and obtain accurate measurement results of slag performance,the volatility degree and deviation mechanism must be ***-isothermal thermogravimetric analysis at different heating rates was used to establish the volatilization kinetic model,and it reveals the volatilization mechanism of CaF2-Na2O-CaO-SiO2-Al2O3-MgO-B2O3 synthetic sodium-containing fluoride mould *** results demonstrated that the evaporation of NaF and SiF4 was the decisive factor that led to the change in composition and deviation of properties of the tested *** most probable kinetic mechanism function for the evaporation of volatile component from sodiumcontaining fluoride mould flux could be expressed by g(α)=[—ln(1-α)]^2/3,with an apparent activation energy of 164.866 kJ mol^-1 and pre-exponential factor of 2.13×10^-4 s^-1,where α is the conversion rate at any time step in the volatilization *** reaction mechanism was random nucleation followed by growth,which was the limiting factor for the volatilization of synthetic sodium-containing fluoride mould *** method of increasing heating rate and adding protection gas in the measurement system will help to obtain more accurate results of slag performance.

关键词： Fluoride Slag performance Volatilization kinetics Thermogravimetric analysis Mechanism function

Mathematical model of slotting manufacture and simulation for cosine gears

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Journal of Central South University 2014年第3期21卷 933-941页

作者：王建罗善明徐攀 School of Mechanical & Automotive Engineering Xiamen University of Technology School of Physics and Mechanical & Electrical Engineering Xiamen University Jianglu Maching and Electronics Group Co. Ltd.

A slotting method for cosine gears was proposed by using the involute cutter based on the conjugate theories of digital surface and gear meshing. The slotting model between the cosine tooth surface represented by discrete points and the cutter figuration determined by analytic function was built for their geometrical relationship and conjugate motion during the machining process. Conjugate points in the cutter section corresponding to the discrete points on the cosine gear tooth surface and the conjugate movements were solved. By using the flexible control of the CNC procedure, the active control of the cutting trace of the slotting cutter was accomplished and the envelop forming of the cosine gear was obtained. Based on the software C++ and Matlab, the computer aided manufacturing(CAM) system of the cosine gear was developed, and the simulation of the slotting process was accomplished. Several examples were provided to illustrate the approach. The result of the simulation demonstrates that the proposed slotting method is feasible.

关键词：计算机辅助制造齿轮啮合数学模型余弦开槽仿真 matlab 主动控制