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Residual Attention-BiConvLSTM:一种新的全球电离层TEC map预测模型
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作者 王浩然 刘海军 +5 位作者 袁静 乐会军 李良超 陈羿 单维锋 袁国铭 《地球物理学报》 北大核心 2025年第2期413-430,共18页
电离层总电子含量(TEC)预测对提高全球卫星导航系统(GNSS)的精度具有重要意义.现有的TEC map预测模型主要通过顺序堆叠时空特征提取单元来实现.这种模型搭建方法会因多个卷积层顺序堆叠而损失细粒度的TEC map的空间特征,导致模型精度不... 电离层总电子含量(TEC)预测对提高全球卫星导航系统(GNSS)的精度具有重要意义.现有的TEC map预测模型主要通过顺序堆叠时空特征提取单元来实现.这种模型搭建方法会因多个卷积层顺序堆叠而损失细粒度的TEC map的空间特征,导致模型精度不够;还会由于多层堆叠导致梯度消失或梯度爆炸问题.本文借鉴残差注意力(Residual Attention)的思想,在TEC map预测模型中增加了残差注意力模块,提出了Residual Attention-BiConvLSTM模型.该模型中的残差注意力模块能同时提取粗、细粒度空间特征,并对其进行加权.本文在全球TEC map数据上与ConvLSTM、ConvGRU、ED-ConvLSTM和C1PG进行了对比实验.实验结果表明,本文所提出的Residual Attention-BiConvLSTM模型的RMSE、MAE、MAPE和R^(2)在太阳活动高年和年均优于对比模型.本文还在一次磁暴事件中对比了5种模型的预测效果.实验结果表明,大磁暴发生时,本文模型与C1PG相近,优于其他3种对比模型.本文的研究工作为电离层map预测模型搭建提供一个新思路. 展开更多
关键词 电离层TEC map预测 残差注意力模块 Residual Attention-BiConvLSTM 时空预测模型
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Study on Color Difference of Color Reproduction of 3D Objects
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作者 GU Chong DENG Yi-qiang 《印刷与数字媒体技术研究》 北大核心 2025年第4期33-38,69,共7页
To investigate the applicability of four commonly used color difference formulas(CIELAB,CIE94,CMC(1:1),and CIEDE2000)in the printing field on 3D objects,as well as the impact of four standard light sources(D65,D50,A,a... To investigate the applicability of four commonly used color difference formulas(CIELAB,CIE94,CMC(1:1),and CIEDE2000)in the printing field on 3D objects,as well as the impact of four standard light sources(D65,D50,A,and TL84)on 3D color difference evaluations,50 glossy spheres with a diameter of 2cm based on the Sailner J4003D color printing device were created.These spheres were centered around the five recommended colors(gray,red,yellow,green,and blue)by CIE.Color difference was calculated according to the four formulas,and 111 pairs of experimental samples meeting the CIELAB gray scale color difference requirements(1.0-14.0)were selected.Ten observers,aged between 22 and 27 with normal color vision,were participated in this study,using the gray scale method from psychophysical experiments to conduct color difference evaluations under the four light sources,with repeated experiments for each observer.The results indicated that the overall effect of the D65 light source on 3D objects color difference was minimal.In contrast,D50 and A light sources had a significant impact within the small color difference range,while the TL84 light source influenced both large and small color difference considerably.Among the four color difference formulas,CIEDE2000 demonstrated the best predictive performance for color difference in 3D objects,followed by CMC(1:1),CIE94,and CIELAB. 展开更多
关键词 Color difference formula 3D objects Light source Gray scale Normalized residual sum of squares
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Infrared small target detection algorithm via partial sum of the tensor nuclear norm and direction residual weighting
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作者 SUN Bin XIA Xing-Ling +1 位作者 FU Rong-Guo SHI Liang 《红外与毫米波学报》 北大核心 2025年第2期277-288,共12页
Aiming at the problem that infrared small target detection faces low contrast between the background and the target and insufficient noise suppression ability under the complex cloud background,an infrared small targe... Aiming at the problem that infrared small target detection faces low contrast between the background and the target and insufficient noise suppression ability under the complex cloud background,an infrared small target detection method based on the tensor nuclear norm and direction residual weighting was proposed.Based on converting the infrared image into an infrared patch tensor model,from the perspective of the low-rank nature of the background tensor,and taking advantage of the difference in contrast between the background and the target in different directions,we designed a double-neighborhood local contrast based on direction residual weighting method(DNLCDRW)combined with the partial sum of tensor nuclear norm(PSTNN)to achieve effective background suppression and recovery of infrared small targets.Experiments show that the algorithm is effective in suppressing the background and improving the detection ability of the target. 展开更多
关键词 infrared small target detection infrared patch tensor model partial sum of the tensor nuclear norm direction residual weighting
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A cohesion loss model for determining residual strength of deep bedded sandstone
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作者 SONG Zhi-xiang ZHANG Jun-wen +12 位作者 ZHANG Yu-jie WU Shao-kang BAI Xu-yang ZHANG Li-chao ZHANG Sui-lin ZHANG Xu-wen FAN Guang-chen LI Wen-jun ZENG Ban-quan WANG Shi-ji SUN Xiao-yan SANG Pei-miao LI Ning 《Journal of Central South University》 2025年第7期2593-2618,共26页
Rock residual strength,as an important input parameter,plays an indispensable role in proposing the reasonable and scientific scheme about stope design,underground tunnel excavation and stability evaluation of deep ch... Rock residual strength,as an important input parameter,plays an indispensable role in proposing the reasonable and scientific scheme about stope design,underground tunnel excavation and stability evaluation of deep chambers.Therefore,previous residual strength models of rocks established were reviewed.And corresponding related problems were stated.Subsequently,starting from the effects of bedding and whole life-cycle evolution process,series of triaxial mechanical tests of deep bedded sandstone with five bedding angles were conducted under different confining pressures.Then,six residual strength models considering the effects of bedding and whole life-cycle evolution process were established and evaluated.Finally,a cohesion loss model for determining residual strength of deep bedded sandstone was verified.The results showed that the effects of bedding and whole life-cycle evolution process had both significant influences on the evolution characteristic of residual strength of deep bedded sandstone.Additionally,residual strength parameters:residual cohesion and residual internal friction angle of deep bedded sandstone were not constant,which both significantly changed with increasing bedding angle.Besides,the cohesion loss model was the most suitable for determining and estimating the residual strength of bedded rocks,which could provide more accurate theoretical guidance for the stability control of deep chambers. 展开更多
关键词 residual strength deep bedded sandstone whole life-cycle evolution process cohesion loss model rock mechanics
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Effects of residual solvent dimethyl formamide on the solid phase ripening of ultrafine explosive 2,2',4,4',6,6'-hexanitrostilbene
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作者 Jincan Zhu Xinfeng Wang +5 位作者 Gang Li Bing Huang Bo Jin Yu Liu Shichun Li Haobin Zhang 《Defence Technology(防务技术)》 2025年第7期128-136,共9页
Nowadays, ultrafine explosives are widely used in military fields. Ultrafine 2,2',4,4',6,6'-hexanitrostilbene(HNS) has emerged as an optimal primer for explosion foil initiators due to its excellent therma... Nowadays, ultrafine explosives are widely used in military fields. Ultrafine 2,2',4,4',6,6'-hexanitrostilbene(HNS) has emerged as an optimal primer for explosion foil initiators due to its excellent thermal stability and high-voltage short-pulse initiation performance. However, the solid phase ripening of ultrafine HNS leads to a degradation in its impact detonation performance. Previous studies have indicated that residual dimethyl formamide(DMF), which is present in ultrafine HNS prepared using the recrystallization method, affects ultrafine HNS ripening. The mechanism of residual solvent effects on solid phase ripening of ultrafine HNS is unclear. In this work, the specific surface area(SSA) derived from small angle X-ray scattering(SAXS) was utilized for kinetic fitting analysis to explore the mechanism by which residual solvents enhance the solid phase ripening of ultrafine HNS. The results of the SSA measured by insitu SAXS under conditions of 150℃ for 40 h revealed that the sample with 0.2% residual DMF exhibited a 21.51% decrease in SSA, whereas the sample with only 0.04% residual DMF showed a decrease of 15.66%.Furthermore, the higher amounts of residual DMF accelerated the reduction in SSA with time. Kinetic fitting analysis demonstrated that reducing residual DMF would lower both the activation energy and the pre-exponential factor, consequently decreasing the rate constant of solid phase ripening. The mechanism was speculated that it primarily facilitated the Ostwald ripening(OR). Additionally, contrast variation small angle X-ray scattering(CV-SAXS) confirmed that coating of ultrafine HNS particles is an effective method for inhibiting ripening, significantly reducing both the rate and extent of ripening of ultrafine HNS. This study predicts how residual solvents impact the solid phase ripening process of ultrafine HNS and proposes strategies for enhancing the long-term stability of ultrafine explosives. 展开更多
关键词 Ultrafine HNS Residual solvent Solid phase ripening Small angle X-ray scattering
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Recovery of molybdenum from residues by simultaneous ultrafine milling and alkali leaching 被引量:1
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作者 杨华明 胡岳华 邱冠周 《Journal of Central South University of Technology》 2002年第2期87-90,共4页
A new technology of treating molybdenum residues by simultaneous ultrafine milling and alkali leaching was put forward to recover molybdenum from metallurgical residues. The effects of residue size, milling time, soli... A new technology of treating molybdenum residues by simultaneous ultrafine milling and alkali leaching was put forward to recover molybdenum from metallurgical residues. The effects of residue size, milling time, solid content, n (Na 2CO 3)/ n (Mo) and slurry pH value on molybdenum leaching rate were investigated. The results indicate that a simpler process, lower slurry temperature, 50% shorter treating time, 60% decrease of Na 2CO 3 content and 15% increase of molybdenum leaching rate can be obtained by the new technology compared with the traditional process. The leaching kinetic equation was determined, and calculation of active energy ( E =56.2 kJ/mol) shows that the leaching process of molybdenum residues by simultaneous ultrafine milling and alkali leaching is controlled by chemical reaction. Potential exists for the new process to form the basis for an economically viable, environmentally friendly process to recover valuable elements from residues. 展开更多
关键词 molybdenum residue ultrafine milling alkali leaching mechanochemical effect kinetic behavior
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Simultaneous production of hydrogen and volatile fatty acids from anaerobic digestion of Macrocystis pyrifera biomass residues
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作者 ZHAO Xiao-xian FAN Xiao-lei +4 位作者 XUE Zhi-xin YANG Zhi-man YUAN Xian-zheng QIU Yan-ling GUO Rong-bo 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第6期1281-1287,共7页
The Macrocystis pyrifera biomass residues(MPBRs) after extraction of algin could be applied in anaerobic fermentation. The effects of different pretreatment conditions, substrate concentrations and initial pH values o... The Macrocystis pyrifera biomass residues(MPBRs) after extraction of algin could be applied in anaerobic fermentation. The effects of different pretreatment conditions, substrate concentrations and initial pH values on hydrogen and volatile fatty acid(VFA) production during the anaerobic fermentation of MPBRs were evaluated. The optimal pretreatment conditions, substrate concentration, initial pH values were determined as thermo-alkaline pretreatment at 100 °C with 0.1 mol/L NaOH, 40 g/L and 7.0, respectively. Under these conditions, the maximum hydrogen production was 11.38 mL/g(volatile solids, VS), which was approximately 23 times higher than that of untreated MPBRs. Furthermore, the maximum total volatile fatty acid(TVFA) yield was found to be 0.055 g/g(VS) and the VFA mainly consisted of acetic and butyric acids. The results indicate that the yield of TVFA is positively correlated with hydrogen production, and the MPBRs could produce hydrogen and TVFA simultaneously. In addition, thermo-alkaline pretreatment is proven to be the best method for hydrogen and VFA production. 展开更多
关键词 Macrocystis pyrifera BIOMASS residues PRETREATMENT FERMENTATION HYDROGEN
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Minerals of Bauxites and Residues: Problems of Processing and Enrichment (Russia)
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作者 Olga Kotova Galina Gasaleeva Aleksandr Vakhrushev 《矿物学报》 CAS CSCD 北大核心 2013年第S1期70-70,共1页
The complex of mineralogical methods was developed to obtain reliable data about mineral composition of bauxites and new crystal-chemical information (the whole cycle of used chemical elements, methods of residue util... The complex of mineralogical methods was developed to obtain reliable data about mineral composition of bauxites and new crystal-chemical information (the whole cycle of used chemical elements, methods of residue utilization, position of residue tails in dump pits). Natural and technogenic structures were studied as sources of necessary chemical elements and useful properties. 展开更多
关键词 MINERAL bauxites MINERAL residues PROCESSING and ENRICHMENT of bauxites and residues
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Determination of Residues and Safety Analysis of Metal Impurities in Platinum-based Antitumor Drugs
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作者 PENG Juan PU Shaoping +3 位作者 LI Guangli HE Jian ZHANG Zhirong LIAO Yunxing 《贵金属》 CAS CSCD 北大核心 2012年第A01期258-262,共5页
The residual metal impurities in cisplatin, carboplatin and oxaliplatin were determined by ICP-AES. The samples were ignited and dissolved with HCl:HNO 3 (3:1). The method is simple and accurate. By the determination ... The residual metal impurities in cisplatin, carboplatin and oxaliplatin were determined by ICP-AES. The samples were ignited and dissolved with HCl:HNO 3 (3:1). The method is simple and accurate. By the determination of the metal residues in the samples, the calculated actual daily exposure and concentration of the metal Pd, Ir, Rh, Ru, Mo, Ni, Cr, V, Cu, Mn, Fe and Zn that were less than the permitted daily exposures (PDE) and the limited concentration permitted in the EMEA guideline on the specification limits for residues of metal catalysts or metal reagents [1] . The metal residues can de adequately removed from the active pharmaceutical ingredients and the corresponding drugs. The trace metal residues will not affect human health and lead to the safety hazard by the intravenous injection. 展开更多
关键词 ICP-AES platinum-based antitumor drug metal reagent residue safety
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Study on ELISA for detection of sulfamethazine residues
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作者 LI Jichang HE Liang XU Shiwen HUO Guicheng DING Liangjun LIU Ning 《Journal of Northeast Agricultural University(English Edition)》 CAS 2007年第3期224-228,共5页
In this study, various factors of ELISA for detection of sulfamethazine residues were explored, the coating antigen was diluted to 1:400, the best coating condition was at 4℃ overnight, the working concentration of ... In this study, various factors of ELISA for detection of sulfamethazine residues were explored, the coating antigen was diluted to 1:400, the best coating condition was at 4℃ overnight, the working concentration of HRP-IgG enzyme conjugate was 1 : 7 000. The pre-incubation time and incubation time was 30 min and 120 min, respectively, the substrate solution working time was 20 min. Two moL · L^-1 H2SO4 was used to stop the reaction and checked. A standard curve of direct competitive ELISA had been established to detect the sulfamethazine residues in milk. The detection limit of this method was 1.97 ng · mL^-1. The mean concentration of sulfamethazine required to inhibit 30% antibody was 7.1 ng · mL^-1. The linear range of the detection was 5-200 ng · mL^-1. The recovery ratio was between 73.20% and 91.16%. The CV% of within array and between arrays was less than 10%. 展开更多
关键词 SULFAMETHAZINE monoclonal antibody ELISA residue detection
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Residues important to the allosteric regulation on ligand binding affinity in β3 integrins
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作者 Jizhong Lou1,Wei Chen2,Mei-Yin Chou3,Cheng Zhu1,2,3,4(1Parker H.Petit Institute for Bioengineering and Bioscience,2Woodruff School of Mechanical Engineering,and 3School of Physics,4Coulter Department of Biomedical Engineering,,Georgia Institute of Technology,GA,USA) 《医用生物力学》 EI CAS CSCD 2009年第S1期20-20,共1页
Integrins are heterodimers that mediate cell adhesion and transduce signals bidirectionally across the cell membrane.Integrins often exist in low affinity(or inactive) states for
关键词 residues important to the allosteric regulation on ligand binding affinity in
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基于GRU-DRSN的双通道人体活动识别 被引量:1
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作者 邵小强 原泽文 +3 位作者 杨永德 刘士博 李鑫 韩泽辉 《科学技术与工程》 北大核心 2024年第2期676-683,共8页
人体活动识别(human activity recognizition, HAR)在医疗、军工、智能家居等领域有很大的应用空间。传统机器学习方法特征提取难度较大且精度不高。针对上述问题并结合传感器时序特性,提出了一种融合CBAM(convolutional block attentio... 人体活动识别(human activity recognizition, HAR)在医疗、军工、智能家居等领域有很大的应用空间。传统机器学习方法特征提取难度较大且精度不高。针对上述问题并结合传感器时序特性,提出了一种融合CBAM(convolutional block attention module)注意力机制的GRU-DRSN双通道并行模型,有效避免了传统串行模型因网络深度加深引起梯度爆炸和消失问题。同时并行结构使得两条支路具有相同的优先级,使用深度残差收缩网络(deep residual shrinkage network, DRSN)提取数据的深层空间特征,同时使用门控循环结构(gated recurrent unit, GRU)学习活动样本在时间序列上的特征,同时进行提取样本不同维度的特征,并通过CBAM模块进行特征的权重分配,最后通过Softmax层进行识别,实现了端对端的人体活动识别。使用公开数据集(wireless sensor data mining, WISDM)进行验证,模型平均精度达到了97.6%,与传统机器学习模型和前人所提神经网络模型相比,有更好的识别效果。 展开更多
关键词 人体活动识别(human activity recognizition HAR) 门控循环结构(gated recurrent unit GRU) 深度残差收缩网络(deep residual shrinkage network DRSN) CBAM 双通道并行
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改进注意力机制嵌入PR-Net模型的水稻病害识别仿真
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作者 路阳 刘鹏飞 +3 位作者 许思源 刘启旺 顾福谦 王鹏 《系统仿真学报》 CAS CSCD 北大核心 2024年第6期1322-1333,共12页
针对现有的CNN模型在水稻叶部病害的识别中准确率较低的问题,提出了一种结合并行结构和残差结构的混合卷积神经网络模型PRC-Net(parallel residual with coordinate attention network)。引入并行结构,提高卷积的感受野;结合残差结构,... 针对现有的CNN模型在水稻叶部病害的识别中准确率较低的问题,提出了一种结合并行结构和残差结构的混合卷积神经网络模型PRC-Net(parallel residual with coordinate attention network)。引入并行结构,提高卷积的感受野;结合残差结构,使特征信息完整的连续传递;在骨干模型PR-Net中嵌入改进的空间注意力机制,增强对不同尺度病斑特征信息的凝聚程度;为进一步提升病害识别的准确率,并减少模型的训练时间和推理时间,通过改变加权方式对模型结构进行优化。仿真结果表明:与InceptionResNetV2等分类模型相比,PRC-Net具有更少的训练参数、更短的训练时间和更高的识别精度,性能优于其他作物病害识别模型。 展开更多
关键词 水稻叶部病害 PRC-Net(parallel residual with coordinate attention network) 卷积神经网络 注意力机制 图像识别
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Determination of Herbicide Chlorsulfuron Residual Kinbetic and Accumulated Residues in Soil by Gas Chromatography
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作者 Xiang Wensheng, Su Shaoquan, Wang Jing, Zhang Ying (Northeast Agricultural University, Harbin 150030, P R China) 《Journal of Northeast Agricultural University(English Edition)》 CAS 1997年第2期131-136,共6页
In this paper, residual kinetic and accumulated residues of chlorsulfuron in soil was studied by Gas chromatograhy. The result identify, chlorsulfuron was applied to winter wheat at rates of 15 g aiha -1 ; 30 g ai... In this paper, residual kinetic and accumulated residues of chlorsulfuron in soil was studied by Gas chromatograhy. The result identify, chlorsulfuron was applied to winter wheat at rates of 15 g aiha -1 ; 30 g ai·ha -1 , degradation on of Half-life in soil were 43.2 days; 36.9 days, respectively, and one year later, the residues in soil were 0.34 ng·g -1 ; 0.43 ng·g -1 , respectively. Chlorsulfuron was applied continuously several years, the residues in soil was accumulated. 展开更多
关键词 CHLORSULFURON residual kinetic accumulated residues.
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Corrosion behavior of co-gasification slag of furfural residue and coal on alumina-silica refractories
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作者 MA Xiaotong WANG Zhigang +8 位作者 LU Hao LIU Wei WANG Yanxia ZHAO Jiangshan SUN Lingmin YAN Jingchong ZHUANG Shujuan LI Huaizhu KONG Lingxue 《燃料化学学报(中英文)》 EI CAS CSCD 北大核心 2024年第10期1387-1397,共11页
Gasification of furfural residue with coal can realize its efficient and clean utilization.But the high alkali metal content in furfural slag is easy to cause the corrosion of gasifier refractory.Two gasification coal... Gasification of furfural residue with coal can realize its efficient and clean utilization.But the high alkali metal content in furfural slag is easy to cause the corrosion of gasifier refractory.Two gasification coals with different silica alumina ratio and a furfural residue were selected in the study.The effects of furfural residue additions on corrosion of silica brick,corundum brick,high alumina brick and mullite brick were investigated by using XRD,SEM-EDS and Factsage Software,and the corrosion mechanism was analyzed.With increasing furfural residue addition,the permeability of the slags to high-aluminium-bearing refractories first decreases and then increases,while the permeability on silica brick shows a slight decrease trend.Leucite(KAlSi_(2)O_(6))with high-melting temperature is generated from the reaction of K_(2)O and SiO_(2)in slag with Al_(2)O_(3)in refractories after furfural residue is added,which hinders the infiltration of slag in refractories.Kaliophilite(KAlSiO_(4))of low-melting point is formed when K_(2)O content increases,and this contributes to the infiltration of slag in refractories.The acid-base reaction between slag and silica brick is distinctly occurred,more slag reacts with SiO_(2)in the silicon brick,resulting in a decrease in the amount of slag infiltrating into the silicon brick as furfural residue is added.The corrosion of silica brick is mainly caused by the acid-base reaction,while the corrosion of three alumina based refractory bricks of corundum,mullite and high alumina brick is determined by slag infiltration.A linear correlation between the percolation rate and slag viscosity is established,the slag permeability increases with decreasing viscosity,resulting in stronger permeability for the high Si/Al ratio slag with lower viscosity. 展开更多
关键词 furfural residue CO-GASIFICATION SLAG REFRACTORY corrosion
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Innovative Research Group of Hunan Province
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《Journal of Central South University》 SCIE EI CAS CSCD 2024年第4期1383-1384,共2页
Team Profile Focusing on the major needs of national ecological civilization construction and soil environmentalprotection,the team systematically carried out researches on mining&metallurgy sites remediation,and ... Team Profile Focusing on the major needs of national ecological civilization construction and soil environmentalprotection,the team systematically carried out researches on mining&metallurgy sites remediation,and the soilformation of bauxite residue.A new model of physical-chemical-biological based ecological disposal for bauxiteresidue was proposed,and a replicable and popularized soil-groundwater collaborative remediation technologyfor smelting sites was formed,with the demonstration projects of 250000 m^(2). 展开更多
关键词 SOIL HUNAN RESIDUE
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Effect of quenching cooling rate on residual stress and microstructure evolution of 6061 aluminum alloy
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作者 HUANG Ke YI You-ping +4 位作者 HUANG Shi-quan HE Hai-lin LIU Jie HUA Hong-en TANG Yun-jian 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第7期2167-2180,共14页
In this study,the cooling rate was manipulated by quenching with water of different temperatures(30,60 and 100℃).Surface and internal residual stresses in the quenched 6061 aluminum alloy samples were measured using ... In this study,the cooling rate was manipulated by quenching with water of different temperatures(30,60 and 100℃).Surface and internal residual stresses in the quenched 6061 aluminum alloy samples were measured using hole-drilling and crack compliance methods,respectively.Then,the processability of the quenched samples was evaluated at cryogenic temperatures.The mechanical properties of the as-aged samples were assessed,and microstructure evolution was analyzed.The surface residual stresses of samples W30℃,W60℃and W100℃is−178.7,−161.7 and−117.2 MPa,respectively along x-direction,respectively;and−191.2,−172.1 and−126.2 MPa,respectively along y-direction.The sample quenched in boiling water displaying the lowest residual stress(~34%and~60%reduction in the surface and core).The generation and distribution of quenching residual stress could be attributed to the lattice distortion gradient.Desirable plasticity was also exhibited in the samples with relatively low quenching cooling rates at cryogenic temperatures.The strengthes of the as-aged samples are 291.2 to 270.1 MPa as the quenching water temperature increase from 30℃to 100℃.Fine and homogeneous β"phases were observed in the as-aged sample quenched with boiling water due to the clusters and Guinier-Preston zones(GP zones)premature precipitated during quenching process. 展开更多
关键词 6061 aluminum alloy residual stress cooling rate cryogenic cooling mechanical properties microstructure evolution
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Analysis model for damage of reinforced bars in RC beams under contact explosion
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作者 Chaozhi Yang Zhengxiang Huang +2 位作者 Xin Jia Wei Shang Jian Zhang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第11期104-118,共15页
The load-bearing capacity of reinforced concrete(RC) beams primarily relies on internal reinforced bars.However, limited research has been conducted on the dynamic response of these bars. To address this gap, this stu... The load-bearing capacity of reinforced concrete(RC) beams primarily relies on internal reinforced bars.However, limited research has been conducted on the dynamic response of these bars. To address this gap, this study has established an analytical model using dimensional analysis for calculating the deformation of reinforced bars within RC beams subjected to contact explosion. Comparison with experimental data reveals that the model has a relative error of 5.22%, effectively reflecting the deformation of reinforced bars. Additionally, based on this model, the study found that while concrete does influence the deformation of reinforced bars, this influence can be disregarded in comparison to the material properties of the bars themselves. The findings of this study have implications for calculating the residual load-bearing capacity of damaged RC beams, evaluating the extent of damage to RC beams after blast loading, and providing guidance for the blast-resistant design of RC structures. 展开更多
关键词 Reinforced concrete beam Contact explosion Reinforced bar Damage analysis Residual load-bearing capacity
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Automatic modulation recognition of radiation source signals based on two-dimensional data matrix and improved residual neural network
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作者 Guanghua Yi Xinhong Hao +3 位作者 Xiaopeng Yan Jian Dai Yangtian Liu Yanwen Han 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期364-373,共10页
Automatic modulation recognition(AMR)of radiation source signals is a research focus in the field of cognitive radio.However,the AMR of radiation source signals at low SNRs still faces a great challenge.Therefore,the ... Automatic modulation recognition(AMR)of radiation source signals is a research focus in the field of cognitive radio.However,the AMR of radiation source signals at low SNRs still faces a great challenge.Therefore,the AMR method of radiation source signals based on two-dimensional data matrix and improved residual neural network is proposed in this paper.First,the time series of the radiation source signals are reconstructed into two-dimensional data matrix,which greatly simplifies the signal preprocessing process.Second,the depthwise convolution and large-size convolutional kernels based residual neural network(DLRNet)is proposed to improve the feature extraction capability of the AMR model.Finally,the model performs feature extraction and classification on the two-dimensional data matrix to obtain the recognition vector that represents the signal modulation type.Theoretical analysis and simulation results show that the AMR method based on two-dimensional data matrix and improved residual network can significantly improve the accuracy of the AMR method.The recognition accuracy of the proposed method maintains a high level greater than 90% even at -14 dB SNR. 展开更多
关键词 Automatic modulation recognition Radiation source signals Two-dimensional data matrix Residual neural network Depthwise convolution
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Impact of correlated private signals on continuous-time insider trading
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作者 ZHOU Yonghui XIAO Kai 《运筹学学报(中英文)》 CSCD 北大核心 2024年第3期97-107,共11页
A model of continuous-time insider trading in which a risk-neutral in-sider possesses two imperfect correlated signals of a risky asset is studied.By conditional expectation theory and filtering theory,we first establ... A model of continuous-time insider trading in which a risk-neutral in-sider possesses two imperfect correlated signals of a risky asset is studied.By conditional expectation theory and filtering theory,we first establish three lemmas:normal corre-lation,equivalent pricing and equivalent profit,which can guarantee to turn our model into a model with insider knowing full information.Then we investigate the impact of the two correlated signals on the market equilibrium consisting of optimal insider trading strategy and semi-strong pricing rule.It shows that in the equilibrium,(1)the market depth is constant over time;(2)if the two noisy signals are not linerly correlated,then all private information of the insider is incorporated into prices in the end while the whole information on the asset value can not incorporated into prices in the end;(3)if the two noisy signals are linear correlated such that the insider can infer the whole information of the asset value,then our model turns into a model with insider knowing full information;(4)if the two noisy signals are the same then the total ex ant profit of the insider is increasing with the noise decreasing,while down to O as the noise going up to infinity;(5)if the two noisy signals are not linear correlated then with one noisy signal fixed,the total ex ante profit of the insider is single-peaked with a unique minimum with respect to the other noisy signal value,and furthermore as the noisy value going to O it gets its maximum,the profit in the case that the real value is observed. 展开更多
关键词 continuous-time insider trading risk neutral private correlated signals linear bayesian equilibrium market depth residual information
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