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A process-level hierarchical structural decomposition analysis (SDA) of energy consumption in an integrated steel plant 被引量:3
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作者 刘骁浚 廖胜明 +1 位作者 饶政华 刘刚 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第2期402-412,共11页
A hierarchical structural decomposition analysis(SDA) model has been developed based on process-level input-output(I-O) tables to analyze the drivers of energy consumption changes in an integrated steel plant during 2... A hierarchical structural decomposition analysis(SDA) model has been developed based on process-level input-output(I-O) tables to analyze the drivers of energy consumption changes in an integrated steel plant during 2011-2013. By combining the principle of hierarchical decomposition into D&L method, a hierarchical decomposition model for multilevel SDA is obtained. The developed hierarchical IO-SDA model would provide consistent results and need less computation effort compared with the traditional SDA model. The decomposition results of the steel plant suggest that the technology improvement and reduced steel final demand are two major reasons for declined total energy consumption. The technical improvements of blast furnaces, basic oxygen furnaces, the power plant and the by-products utilization level have contributed mostly in reducing energy consumption. A major retrofit of ancillary process units and solving fuel substitution problem in the sinter plant and blast furnace are important for further energy saving. Besides the empirical results, this work also discussed that why and how hierarchical SDA can be applied in a process-level decomposition analysis of aggregated indicators. 展开更多
关键词 structural decomposition analysis input-output table energy consumption embodied energy integrated steel plant
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Composition analysis and hpyerglycemic activity of the fruit of Phyllanthus emblica L.
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作者 Chun-pengWAN 《中国药理学与毒理学杂志》 CAS CSCD 北大核心 2015年第S1期37-37,共1页
OBJECTIVE To investigate the hpyerglycemic activity and elucidate the active composition of the fruit of Phyllanthus emblica L.,an edible and medicinal plant used for traditional Chinese medicine and Tibetan medicine ... OBJECTIVE To investigate the hpyerglycemic activity and elucidate the active composition of the fruit of Phyllanthus emblica L.,an edible and medicinal plant used for traditional Chinese medicine and Tibetan medicine to cure the blood disease,bacon disease,liver disease,heart disease and hypertension.METHODS The LO2 normal liver cell lines were used to investigate the hpyerglycemic activity,The LO2 cells were treated with 100,200 and 400μg·mL-1 extracts of P.emblica L.;real-Time PCR was used to detect the expression of glucose transporter type 2(GLUT-2)and peroxisome proliferator-activated receptor-γ(PPARγ)mRNA.The PPRE(peroxisome proliferator response element)and NF-κB activities were detected by luciferase method.The chemical compositions were analyzed by HPLC-MS.RESULTS The expression of GLUT-2 and PPARγmRNA were significantly increased treated with 400μg·mL-1 extracts of P.emblica L.(P<0.05)and in a dose-dependant manner;PPRE activity was significantly increased in a dosedependant manner(P<0.05);however,NF-κB activity induced by LPS was inhibited also in a dose-dependant manner(P<0.05).The chemical composition analyzed by HPLC-MS showed that the gallic acid was the major component in P.emblica L.CONCLUSION P.emblica L.showed promising hpyerglycemic activity and the gallic acid was the main constituent. 展开更多
关键词 composition analysis hpyerglycemic ACTIVITY Phylla
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Automated body composition analysis system based on chest CT for evaluating content of muscle and adipose 被引量:2
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作者 YANG Jie LIU Yanli +2 位作者 CHEN Xiaoyan CHEN Tianle LIU Qi 《中国医学影像技术》 CSCD 北大核心 2024年第8期1242-1248,共7页
Objective To establish a body composition analysis system based on chest CT,and to observe its value for evaluating content of chest muscle and adipose.Methods T7—T8 layer CT images of 108 pneumonia patients were col... Objective To establish a body composition analysis system based on chest CT,and to observe its value for evaluating content of chest muscle and adipose.Methods T7—T8 layer CT images of 108 pneumonia patients were collected(segmented dataset),and chest CT data of 984 patients were screened from the COVID 19-CT dataset(10 cases were randomly selected as whole test dataset,the remaining 974 cases were selected as layer selection dataset).T7—T8 layer was classified based on convolutional neural network(CNN)derived networks,including ResNet,ResNeXt,MobileNet,ShuffleNet,DenseNet,EfficientNet and ConvNeXt,then the accuracy,precision,recall and specificity were used to evaluate the performance of layer selection dataset.The skeletal muscle(SM),subcutaneous adipose tissue(SAT),intermuscular adipose tissue(IMAT)and visceral adipose tissue(VAT)were segmented using classical fully CNN(FCN)derived network,including FCN,SegNet,UNet,Attention UNet,UNET++,nnUNet,UNeXt and CMUNeXt,then Dice similarity coefficient(DSC),intersection over union(IoU)and 95 Hausdorff distance(HD)were used to evaluate the performance of segmented dataset.The automatic body composition analysis system was constructed based on optimal layer selection network and segmentation network,the mean absolute error(MAE),root mean squared error(RMSE)and standard deviation(SD)of MAE were used to evaluate the performance of automatic system for testing the whole test dataset.Results The accuracy,precision,recall and specificity of DenseNet network for automatically classifying T7—T8 layer from chest CT images was 95.06%,84.83%,92.27%and 95.78%,respectively,which were all higher than those of the other layer selection networks.In segmentation of SM,SAT,IMAT and overall,DSC and IoU of UNet++network were all higher,while 95HD of UNet++network were all lower than those of the other segmentation networks.Using DenseNet as the layer selection network and UNet++as the segmentation network,MAE of the automatic body composition analysis system for predicting SM,SAT,IMAT,VAT and MAE was 27.09,6.95,6.65 and 3.35 cm 2,respectively.Conclusion The body composition analysis system based on chest CT could be used to assess content of chest muscle and adipose.Among them,the UNet++network had better segmentation performance in adipose tissue than SM. 展开更多
关键词 body composition THORAX muscle skeletal adipose tissue deep learning tomography X-ray computed
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Species Composition and Diversity Analysis of Lava Flow in Different Periods in Wudalianchi Nature Reserve,China
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作者 Huang Qing-yang Zhu Dao-guan +2 位作者 Cao Hong-jie Xie Li-hong Ni Hong-wei 《Journal of Northeast Agricultural University(English Edition)》 CAS 2018年第4期22-28,共7页
The species composition and succession discipline after eruption of volcanoes in Wudalianchi Nature Reserve, China, including new volcanoes, such as Huoshao and Laohei Mountains, and old volcanoes, such as East Jiaode... The species composition and succession discipline after eruption of volcanoes in Wudalianchi Nature Reserve, China, including new volcanoes, such as Huoshao and Laohei Mountains, and old volcanoes, such as East Jiaodebu, Wohu and North Gelaqiu Mountains, in different historical periods were investigated by adopting the concept of space as a substitute for time. The species composition, community characteristics and diversity analysis in the remains of volcanic lava flow at various stages were analyzed. The results showed that 192 types of vascular plants that belonged to 50 families and 126 genera in the survey areas existed in the restoration process of primary succession. At the same time, the agglomeration process of plant community succession and the diversity of dominant community were investigated, and the changes in plant diversity at different succession stages were calculated using Margalef, Simpson, Shannon–Wiener, Pielou, Jaccard and Cody indices. 展开更多
关键词 plant diversity species composition SUCCESSION VOLCANO
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Analysis of Temporal Changes in Botanical Composition of a Long-term Grazing Experiment in Nixinasuno, Japan
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作者 YIRu-han MASAEShiyomi +1 位作者 SHIGEOTakahashi TADAKATSUOkubo 《Journal of Northeast Agricultural University(English Edition)》 CAS 2004年第1期47-51,共5页
In order to understand the temporal changes of botanical composition in grassland ecosystem, and to clarify the relation between these changes and environmental impacts, such as climatic factors and artificial disturb... In order to understand the temporal changes of botanical composition in grassland ecosystem, and to clarify the relation between these changes and environmental impacts, such as climatic factors and artificial disturbance, a grazing trail was carried out during a 21-year period from 1974 at a sown grassland of the National Grassland Research Institute, located in Nishinasuno, the central area of Japan. The data sets of biomass for each mouth(from April to November)of the 21 year period were analyzed in this paper. The botanical composition of aboveground biomass varied greatly with both season and year. The biomass ratio of improved herbage species to invaded native plants gradually decreased each year. This may have been owing to meteorological factors, such as low air-temperature in winter, dry and hot summers, grassland management(including grazing intensity and fertilizer application), and inter-specific competition between native and introduced herbage plants. 展开更多
关键词 botanical composition grazing intensity grazing pasture temporal change nitrogen application
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Non-Isothermal Kinetic Analysis of Thermal Decomposition of the Ca-Bentonite from Santai, China
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作者 ZHANG Xianghui HE Chuan +3 位作者 WANG Ling DENG Miao LIU Jing FENG Qian 《矿物学报》 CAS CSCD 北大核心 2013年第S1期138-138,共1页
The thermal decompositions of Ca-bentonites (CaB) from Santai ,Shichuan Province, China over the temperature rage of 30-1100℃ were investigated by simultaneous thermal analyzer. Non-isothermal Kinetic analysis were e... The thermal decompositions of Ca-bentonites (CaB) from Santai ,Shichuan Province, China over the temperature rage of 30-1100℃ were investigated by simultaneous thermal analyzer. Non-isothermal Kinetic analysis were employed to study the thermal decomposition mechanism by using Netzsch Thermokinetics software. The dependence of the activation energy on conversion degree were evaluated by isoconversional methods. The probably mechanism and the corresponding kinetic parameters were determined by multivariate non-linear regression program. 展开更多
关键词 NON-ISOTHERMAL KINETIC SIMULTANEOUS THERMAL analysis CA-BENTONITE THERMAL d
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Products of multiplication,composition and differentiation on weighted Bergman spaces in the unit ball
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作者 ZHANG Chao QIN Yuehai 《中山大学学报(自然科学版)(中英文)》 北大核心 2025年第2期160-169,共10页
The boundness and compactness of products of multiplication,composition and differentiation on weighted Bergman spaces in the unit ball are studied.We define the differentiation operator on the space of holomorphic fu... The boundness and compactness of products of multiplication,composition and differentiation on weighted Bergman spaces in the unit ball are studied.We define the differentiation operator on the space of holomorphic functions in the unit ball by radial derivative.Then we extend the Sharma's results. 展开更多
关键词 composition operator multiplication operator differentiation operator weighted Bergman space
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Effect of Nitrocellulose-modified HTPB Binder on the Thermal Decomposition Behavior of Ammonium Nitrate/Magnesium Solid Propellant
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作者 Mohammed Jouini Amir Abdelaziz +4 位作者 Ahmed Fouzi Tarchoun Fateh Chalghoum Yash Pal Weiqiang Pang Djalal Trache 《火炸药学报》 北大核心 2025年第4期372-381,I0004,共11页
An energetic binder based on hydroxyl-terminated polybutadiene(HTPB),doped with different ratios of nitrocellulose(NC)(10%,20%,30%,and 50%),was developed to study the effect of NC doping on the thermal decomposition b... An energetic binder based on hydroxyl-terminated polybutadiene(HTPB),doped with different ratios of nitrocellulose(NC)(10%,20%,30%,and 50%),was developed to study the effect of NC doping on the thermal decomposition behavior of a composite propellant(CP)comprising ammonium nitrate(AN)as an oxidizer and magnesium(Mg)as a fuel.Optimization of the propellant formulation was conducted using Chemical Equilibrium with Applications-National Aeronautics and Space Administration(CEA-NASA)software,which demonstrated an increase in specific impulse by 12.09 s when the binder contained 50%NC.Fourier-transform infrared spectroscopy(FTIR)analysis confirmed the excellent compatibility between the components,and density measurements revealed an increase of 6.4%with a higher NC content.Morphological analysis using optical microscopy showed that NC doping improved the uniformity and compactness of the surface,reduced cavities,and achieved a more homogeneous particle distribution.Differential scanning calorimetry(DSC)analysis indicated a decrease in the decomposition temperature of the propellant as the NC content increased,while kinetic studies revealed a 48.68%reduction in the activation energy when 50%NC was incorporated into the binder.These findings suggest that the addition of NC enhances combustion efficiency and improves overall propellant performance.This study highlights the potential of the new HTPB-NC energetic binder as a promising approach for advancing solid propellant technology. 展开更多
关键词 physical chemistry composite propellant HTPB NITROCELLULOSE energetic binder thermal behavior
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Multi-omics Analysis of NUDT19 Across Cancer Types and Its Functional Role in Leukemia
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作者 LI Xiao-Jin FENG Shuai +1 位作者 YUAN Zhong-Tao YANG Tong-Hua 《生物化学与生物物理进展》 北大核心 2025年第10期2627-2649,共23页
Objective Recent studies have highlighted the critical role of NUDT19 in the initiation,progression,and prognosis of specific cancer types.However,its involvement in pan-cancer analysis has not been fully characterize... Objective Recent studies have highlighted the critical role of NUDT19 in the initiation,progression,and prognosis of specific cancer types.However,its involvement in pan-cancer analysis has not been fully characterized.This study aims to systematically explore the expression patterns,clinical significance,and immune-related functions of NUDT19 in various cancer types through multi-omics analysis,further revealing its potential role in cancer,particularly its functional and therapeutic target value in leukemia.Methods To achieve this goal,various bioinformatics approaches were employed to evaluate the expression patterns,clinical significance,and immune-related functions of NUDT19 in tumors and normal tissues.Additionally,we analyzed the mutation characteristics of NUDT19 and its relationship with epigenetic modifications.Using the single-cell analysis tool SingleCellBase,we explored the distribution of NUDT19 across different cell subpopulations in tumors.To validate these findings,qRT-PCR was used to measure NUDT19 expression levels in specific tumor cell lines,and we established acute myeloid leukemia(AML)cell lines(HL-60 and THP-1)to conduct NUDT19 knockdown and overexpression experiments,assessing its effects on leukemia cell proliferation,apoptosis,and invasion.Results Pan-cancer analysis revealed the dysregulated expression of NUDT19 across multiple cancer types,which was closely associated with poor prognosis,clinical staging,and diagnostic markers.Furthermore,NUDT19 was significantly correlated with tumor biomarkers,immune-related genes,and immune cell infiltration in different cancers.Mutation analysis showed that multiple mutations in NUDT19 were significantly associated with epigenetic changes.Single-cell analysis revealed the heterogeneity of NUDT19 expression in cancer cells,suggesting its potentially diverse functional roles in different cell subpopulations.qRT-PCR experiments confirmed the significant upregulation of NUDT19 in various tumor cell lines.In AML cell lines,NUDT19 knockdown led to reduced cell proliferation and invasion,with increased apoptosis,while NUDT19 overexpression significantly enhanced cell proliferation and invasion while reducing apoptosis.Conclusion This study demonstrates the diverse roles of NUDT19 in various cancer types,with a particularly prominent functional role in leukemia.NUDT19 is not only associated with tumor initiation and progression but may also influence cancer progression through the regulation of immune microenvironment and epigenetic mechanisms.Our research highlights the potential of NUDT19 as a therapeutic target,particularly for targeted therapies in malignancies such as leukemia,with significant clinical application prospects. 展开更多
关键词 NUDT19 pan-cancer immunotherapeutic single-cell analysis
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Transcriptomics Analysis of Penicillium expansumΔWSC1 Infection and Defense Mechanism against It in Pear Fruits
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作者 ZHAO Lina HU Yize +4 位作者 SHU Yuling Solairaj DHANASEKARAN ZHANG Xiaoyun YANG Qiya ZHANG Hongyin 《食品科学》 北大核心 2025年第13期75-85,共11页
The WSC proteins produced by Penicillium expansum play a crucial role in causing blue mold on pears.To analyze the role of the WSC1 gene in the pathogenic process of this fungal pathogen,we conducted transcriptomic an... The WSC proteins produced by Penicillium expansum play a crucial role in causing blue mold on pears.To analyze the role of the WSC1 gene in the pathogenic process of this fungal pathogen,we conducted transcriptomic analysis of a WSC1 knockout(ΔWSC1)strain.The knockout of WSC1 significantly altered the gene expression profile in P.expansum,particularly for genes involved in cell wall integrity,signaling,stress response,and toxin production.The differential expression of these genes might make theΔWSC1 strain more vulnerable to environmental stress,while reducing the toxin production capacity,ultimately leading to a decrease in the pathogenicity.The transcriptomic analysis revealed that the expression of genes related to stress response signals,defense mechanisms and oxidative stress management changed when pear fruits were infected with theΔWSC1 strain.These changes may trigger a cascade of responses in pear fruits.In addition,compared with those infected with the wild-type strain,pear fruits infected with theΔWSC1 strain exhibited up-regulated expression of genes related to defense and oxidative stress.This study clarifies how the WSC1 gene influences P.expansum’s ability to infect pear fruits and how pear fruits respond to the infection. 展开更多
关键词 pear fruit Penicillium expansum transcriptomic analysis INFECTION
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Influencing factor of the characterization and restoration of phase aberrations resulting from atmospheric turbulence based on Principal Component Analysis
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作者 WANG Jiang-pu-zhen WANG Zhi-qiang +2 位作者 ZHANG Jing-hui QIAO Chun-hong FAN Cheng-yu 《中国光学(中英文)》 北大核心 2025年第4期899-907,共9页
Restoration of phase aberrations is crucial for addressing atmospheric turbulence in light propagation.Traditional restoration algorithms based on Zernike polynomials(ZPs)often encounter challenges related to high com... Restoration of phase aberrations is crucial for addressing atmospheric turbulence in light propagation.Traditional restoration algorithms based on Zernike polynomials(ZPs)often encounter challenges related to high computational complexity and insufficient capture of high-frequency phase aberration components,so we proposed a Principal-Component-Analysis-based method for representing phase aberrations.This paper discusses the factors influencing the accuracy of restoration,mainly including the sample space size and the sampling interval of D/r_(0),on the basis of characterizing phase aberrations by Principal Components(PCs).The experimental results show that a larger D/r_(0)sampling interval can ensure the generalization ability and robustness of the principal components in the case of a limited amount of original data,which can help to achieve high-precision deployment of the model in practical applications quickly.In the environment with relatively strong turbulence in the test set of D/r_(0)=24,the use of 34 terms of PCs can improve the corrected Strehl ratio(SR)from 0.007 to 0.1585,while the Strehl ratio of the light spot after restoration using 34 terms of ZPs is only 0.0215,demonstrating almost no correction effect.The results indicate that PCs can serve as a better alternative in representing and restoring the characteristics of atmospheric turbulence induced phase aberrations.These findings pave the way to use PCs of phase aberrations with fewer terms than traditional ZPs to achieve data dimensionality reduction,and offer a reference to accelerate and stabilize the model and deep learning based adaptive optics correction. 展开更多
关键词 phase aberration atmospheric turbulence principal component analysis Zernike polynomials
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Error Analysis of MSAV Scheme for Two Phase Magnetohydrodynamic Diffuse Interface Model
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作者 HU Kun WANG Danxia +1 位作者 ZHANG Jianwen JIA Hongen 《应用数学》 北大核心 2025年第2期348-371,共24页
In this paper,we develop a multi-scalar auxiliary variables(MSAV)scheme for the Cahn-Hilliard Magnetohydrodynamics system by introducing two scalar auxiliary variables(SAV).This scheme is linear,fully decoupled and un... In this paper,we develop a multi-scalar auxiliary variables(MSAV)scheme for the Cahn-Hilliard Magnetohydrodynamics system by introducing two scalar auxiliary variables(SAV).This scheme is linear,fully decoupled and unconditionally stable in energy.Subsequently,we provide a detailed implementation procedure for full decoupling.Thus,at each time step,only a series of linear differential equations with constant coefficients need to be solved.To validate the effectiveness of our approach,we conduct an error analysis for this first-order scheme.Finally,some numerical experiments are provided to verify the energy dissipation of the system and the convergence of the proposed approach. 展开更多
关键词 Cahn-Hilliard Magnetohydrodynamics system Fully decoupled Stability in energy Error analysis
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Simulation and Experimental Analysis of Mechanical Properties of a Bidirectional Adjustable Magnetorheological Fluid Damper
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作者 YANG Zhi−rong YE Zhong−min +2 位作者 LIU Jin−liang RAO Zhu−shi XIAO Wang−qiang 《船舶力学》 北大核心 2025年第6期1000-1012,共13页
The aim of this study is to address the issues associated with traditional magnetorheological fluid(MRF)dampers,such as insufficient damping force after power failure and susceptibility to settlement.In order to achie... The aim of this study is to address the issues associated with traditional magnetorheological fluid(MRF)dampers,such as insufficient damping force after power failure and susceptibility to settlement.In order to achieve this,a bidirectional adjustable MRF damper was designed and developed.Magnetic field simulation analysis was conducted on the damper,along with simulation analysis on its dynamic characteristics.The dynamic characteristics were ultimately validated through experimental testing on the material testing machine,thereby corroborating the theoretical simulation results.Concurrently,this process generated valuable test data for subsequent implementation of the semi-active vibration control system.The simulation and test results demonstrate that the integrated permanent magnet effectively accomplishes bidirectional regulation.The magnetic induction intensity of the damping channel is 0.2 T in the absence of current,increases to 0.5 T when a maximum forward current of 4 A is applied,and becomes 0 T when a maximum reverse current of 3.8 A is applied.When the excitation amplitude is 8 mm and the frequency is 2 Hz,with the applied currents varying,the maximum damping force reaches 8 kN,while the minimum damping force measures at 511 N.Additionally,at zero current,the damping force stands at 2 kN,which aligns closely with simulation results.The present paper can serve as a valuable reference for the design and research of semi-active MRF dampers. 展开更多
关键词 magnetorheological fluid(MRF) DAMPER permanent magnet finite element analysis test of mechanical properties
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Research on structural design and mechanical properties of precision electroplating machinery for automobiles based on finite element analysis
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作者 Wang Jie Jiang Xiaobei 《电镀与精饰》 北大核心 2025年第11期10-21,共12页
Design a precision electroplating mechanical structure for automobiles based on finite element analysis method and analyze its mechanical properties.Taking the automobile steering knuckle as the research object,ABAQUS... Design a precision electroplating mechanical structure for automobiles based on finite element analysis method and analyze its mechanical properties.Taking the automobile steering knuckle as the research object,ABAQUS parametric modeling technology is used to construct its three-dimensional geometric model,and geometric simplification is carried out.Two surface treatment processes,HK-35 zinc nickel alloy electroplating and pure zinc electroplating,were designed,and the influence of different coatings on the mechanical properties of steering knuckles was compared and analyzed through numerical simulation.At the same time,standard specimens were prepared for salt spray corrosion testing and scratch method combined strength testing to verify the numerical simulation results.The results showed that under emergency braking and composite working conditions,the peak Von Mises stress of the zinc nickel alloy coating was 119.85 MPa,which was lower than that of the pure zinc coating and the alkaline electroplated zinc layer.Its equivalent strain value was 652×10^(-6),which was lower than that of the pure zinc coating and the alkaline electroplated zinc layer.Experimental data confirms that zinc nickel alloy coatings exhibit significant advantages in stress distribution uniformity,strain performance,and load-bearing capacity in high stress zones.The salt spray corrosion test further indicates that the coating has superior corrosion resistance and coating substrate interface bonding strength,which can significantly improve the mechanical stability and long-term reliability of automotive precision electroplating mechanical structures. 展开更多
关键词 finite element analysis electroplating machinery structure mechanical properties electroplating process salt spray corrosion bonding strength
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High-precision quantitative analysis of 3-nitro-1,2,4-triazol-5-one(NTO)concentration based on ATR-FTIR spectroscopy and machine learning
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作者 Zhe Zhang Zhuowei Sun +4 位作者 Haoming Zou Xijuan Lv Ziyang Guo Shuai Zhao Qinghai Shu 《Defence Technology(防务技术)》 2025年第10期131-141,共11页
3-Nitro-1,2,4-triazol-5-one(NTO)is a typical high-energy,low-sensitivity explosive,and accurate concentration monitoring is critical for crystallization process control.In this study,a high-precision quantitative anal... 3-Nitro-1,2,4-triazol-5-one(NTO)is a typical high-energy,low-sensitivity explosive,and accurate concentration monitoring is critical for crystallization process control.In this study,a high-precision quantitative analytical model for NTO concentration in ethanol solutions was developed by integrating real-time ATR-FTIR spectroscopy with chemometric and machine learning techniques.Dynamic spectral data were obtained by designing multi-concentration gradient heating-cooling cycle experiments,abnormal samples were eliminated using the isolation forest algorithm,and the effects of various preprocessing methods on model performance were systematically evaluated.The results show that partial least squares regression(PLSR)exhibits superior generalization ability compared to other models.Vibrational bands corresponding to C=O and–NO_(2)were identified as key predictors for concentration estimation.This work provides an efficient and reliable solution for real-time concentration monitoring during NTO crystallization and holds significant potential for process analytical applications in energetic material manufacturing. 展开更多
关键词 ATR-FTIR spectroscopy Machine learning Quantitative analysis
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Phylogenetic Analysis of Response of Sagittaria trifolia Linn.var.trifolia Genotypes of Northeast China to an Acetohydroxy Acid Synthase Inhibiting Herbicide
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作者 Sun Zhonghua Zhu He +5 位作者 Zou Yize Cao Shihan Wang Xingya He Fuli Ji Mingshan Han Yujun 《Journal of Northeast Agricultural University(English Edition)》 2025年第3期1-13,共13页
Sagittaria trifolia L.is a perennial aquatic herb that primarily reproduces clonally and through generative propagation.In recent years,S.trifolia has evolved a drastic resistance to acetohydroxy acid synthase(AHAS)-i... Sagittaria trifolia L.is a perennial aquatic herb that primarily reproduces clonally and through generative propagation.In recent years,S.trifolia has evolved a drastic resistance to acetohydroxy acid synthase(AHAS)-inhibiting herbicides in Northeast China.The phylogeographic patterns of S.trifolia with 31 purified resistance genotypes and five sensitive genotypes using chloroplast DNA(cpDNA)atpB-rbcL intergenic spacers were studied.Five haplotypes were characterized,and two of them were widely distributed in 36 genotypes.The dose response to bensulfuron-methyl showed that the GR50 ranged from 2.07 g a.i.·hm^(-2) to 220.15 g a.i.·hm^(-2).Sequencing of the AHAS gene indicated that 17 genotypes with the Pro197 mutation were distributed in haplotype 1,six genotypes with the Trp574 mutation were distributed in haplotype 3,and 13 genotypes with the wild AHAS gene were distributed in haplotypes 2,4 and 5.In the minimum-spanning network,the ancestral haplotypes 1 and 2 were widely distributed.Two primary clades were separated in the Bayes tree,and the result was consistent with the maximum likelihood tree. 展开更多
关键词 Sagittaria trifolia L. phylogeographic analysis HAPLOTYPE bensulfuron-methyl resistance
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Novel grey variation relational analysis model for panel data and its application
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作者 WU Honghua QU Zhongfeng 《Journal of Systems Engineering and Electronics》 2025年第2期483-493,共11页
Based on the variation of discrete surface,a new grey relational analysis model,called the grey variation relational ana-lysis(GVRA)model,is proposed in this paper.Meanwhile,the proposed model avoids the inconsistent ... Based on the variation of discrete surface,a new grey relational analysis model,called the grey variation relational ana-lysis(GVRA)model,is proposed in this paper.Meanwhile,the proposed model avoids the inconsistent results caused by diffe-rent construction of discrete surface of panel data or the change in the order of indicators or objects in existing grey relational analysis models.Firstly,the submatrix of the sample matrix is given according to the permutation and combination theory.Secondly,the amplitude of the submatrix is calculated and the variation of discrete surface is obtained.Then,a grey relational coefficient is presented by variation difference,and the GVRA model is established.Furthermore,the properties of the pro-posed model,such as normality,symmetry,reflexivity,transla-tion invariant,and number multiplication invariant,are also veri-fied.Finally,the proposed model is used to identify the driving factors of haze in the cities along the Yellow River in Shandong Province,China.The result reveals that the proposed model can effectively measure the relationship between panel data. 展开更多
关键词 grey relational analysis grey system theory varia-tion discrete surface.
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Reliability analysis of modular charge swinging-loading positioning accuracy under new failure criterion based on spatial geometric relationship
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作者 Zihan Wang Linfang Qian +3 位作者 Liu Yang Taisu Liu Weiwei Chen Haolin Zhang 《Defence Technology(防务技术)》 2025年第6期115-130,共16页
The swinging-loading process is essential for automatic artillery loading systems.This study focuses on the problems of reliability analysis that affect swinging-loading positioning accuracy.A dynamic model for a mult... The swinging-loading process is essential for automatic artillery loading systems.This study focuses on the problems of reliability analysis that affect swinging-loading positioning accuracy.A dynamic model for a multi degree-of-freedom swinging-loading-integrated rigid-flexible coupling system is established.This model is based on the identification of key parameters and platform experiments.Based on the spatial geometric relationship between the breech and loader during modular charge transfer and the possible maximum interference depth of the modular charge,a new failure criterion for estimating the reliability of swinging-loading positioning accuracy is proposed.Considering the uncertainties in the operation of the pendulum loader,the direct probability integration method is introduced to analyze the reliability of the swinging-loading positioning accuracy under three different charge numbers.The results indicate that under two and four charges,the swinging-loading process shows outstanding reliability.However,an unstable stage appears when the swinging motion occurred under six charges,with a maximum positioning failure probability of 0.0712.A comparison between the results obtained under the conventional and proposed criteria further reveals the effectiveness and necessity of the proposed criterion. 展开更多
关键词 Artillery loading system Pendulum loader Dynamic model Failure criterion Reliability analysis
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Analysis of auxiliary antenna array effect on performance of wideband noncooperative interference cancellation
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作者 LI Zheyu LI Yaxing +3 位作者 WANG Ze LIANG Jiaqi HE Fangmin MENG Jin 《Journal of Systems Engineering and Electronics》 2025年第5期1188-1201,共14页
In wideband noncooperative interference cancellation,the reference signals obtained through auxiliary antennas are weighted to cancel with the interference signal.The correlation between the reference signal and the i... In wideband noncooperative interference cancellation,the reference signals obtained through auxiliary antennas are weighted to cancel with the interference signal.The correlation between the reference signal and the interference signal determines interference cancellation performance,while the auxiliary antenna array affects the correlation by influencing the amplitude and phase of the reference signals.This paper analyzes the effect of auxiliary antenna array on multiple performances of wideband noncooperative interference cancellation.Firstly,the array received signal model of wideband interference is established,and the weight vector coupled with the auxiliary antennas array manifold is solved by spectral analysis and eigen-subspace decomposition.Then,multiple performances which include cancellation resolution,grating null,wideband interference cancellation ratio(ICR),and convergence rate are quantitatively characterized with the auxiliary antenna array.It is obtained through analysis that the performances mutually restrict the auxiliary antenna array.Higher cancellation resolution requires larger array aperture,but when the number of auxiliary antennas is fixed,larger array aperture results in more grating nulls.When the auxiliary antennas are closer to the main antenna,the wideband ICR is improved,but the convergence rate is reduced.The conclusions are verified through simulation of one-dimensional uniform array and two-dimensional nonuniform array.The experiments of three arrays are compared,and the results conform well with simulation and support the theoretical analysis. 展开更多
关键词 auxiliary antenna array noncooperative interference cancellation wideband interference performance analysis
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Micromechanical analysis of particle corner effect on bearing and deformation behaviors of coral sand slope foundation under a strip footing
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作者 PENG Yu LUO Zhao-gang +2 位作者 HE Shao-heng QU Li-ming DING Xuan-ming 《Journal of Central South University》 2025年第2期624-642,共19页
To understand the specific behaviors of coastal coral sand slope foundations,discrete element method(DEM)was employed to examine the effect of breakable particle corners on the performance of coral sand slope foundati... To understand the specific behaviors of coastal coral sand slope foundations,discrete element method(DEM)was employed to examine the effect of breakable particle corners on the performance of coral sand slope foundations under a strip footing,from macro to micro scales.The results demonstrate that the bearing characteristics of coral sand slope foundations can be successfully modeled by utilizing breakable corner particles in simulations.The dual effects of interlocking and breakage of corners well explained the specific shallower load transmission and narrower shear stress zones in breakable corner particle slopes.Additionally,the study revealed the significant influence of breakable corners on soil behaviors on slopes.Furthermore,progressive corner breakage within slip bands was successfully identified as the underling mechanism in determining the unique bearing characteristics and the distinct failure patterns of breakable corner particle slopes.This study provides a new perspective to clarify the behaviors of slope foundations composed of breakable corner particle materials. 展开更多
关键词 micromechanical analysis coral sand slope foundation particle corner breakage corner interlock
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