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行-混合随机变量阵列加权和的完全收敛性(英文) 被引量:1
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作者 冯凤香 王定成 《应用数学》 CSCD 北大核心 2016年第3期503-513,共11页
本文研究随机变量阵列加权和的完全收敛性问题,我们获得行-混合随机变量阵列加权和的一个完全收敛性定理.通过这个定理可以获得一系列结果.我们所得结果推广了Baum和Katz(1965),Peligrad和Gut(1999)所得的结果.
关键词 完全收敛性 加权和 -混合随机变量
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-混合序列的强大数律和收敛速度
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作者 王建楷 杨文志 庞飞 《合肥学院学报(自然科学版)》 2010年第1期15-17,共3页
对于正相协和负相协随机变量序列,许多学者都进行了研究,并给出相关结果.受前人研究成果的启发,利用一般方法证明了-混合序列的强大数定律,并且得到了它的收敛速度和上确界的可积性.
关键词 -混合序列 强大数律 收敛速度
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-混合样本下线性模型误差分布的相合核估计
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作者 李玥 张增 《常州工学院学报》 2011年第1期42-46,共5页
对于有公共的未知分布密度f(x)的一个线性模型的误差序列,首先利用收敛系统原理证明了回归系数β的最小二乘估计的相合性,然后由-混合序列的矩不等式,得到了f(x)的核估计■n(x)的逐点弱相合性。
关键词 线性模型 -混合样本 最小二乘估计 核估计 相合性
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_-混合序列的几乎处处收敛性
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作者 张园园 魏永利 +1 位作者 王学军 胡舒合 《合肥学院学报(自然科学版)》 2010年第1期12-14,共3页
文章讨论了ρ-混合序列的几乎处处收敛性,把独立同分布随机变量序列的相应结果较好地推广到同分布ρ-混合序列,从而得到了若干个关于五一混合序列的几乎处处收敛定理.
关键词 -混合序列 几乎处处收敛 独立同分布
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Enhancing rock fragmentation prediction in mining operations:A hybrid GWO-RF model with SHAP interpretability 被引量:1
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作者 ZHANG Yu-lin QIU Yin-gui +2 位作者 ARMAGHANI Danial Jahed MONJEZI Masoud ZHOU Jian 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第8期2916-2929,共14页
In the mining industry,precise forecasting of rock fragmentation is critical for optimising blasting processes.In this study,we address the challenge of enhancing rock fragmentation assessment by developing a novel hy... In the mining industry,precise forecasting of rock fragmentation is critical for optimising blasting processes.In this study,we address the challenge of enhancing rock fragmentation assessment by developing a novel hybrid predictive model named GWO-RF.This model combines the grey wolf optimization(GWO)algorithm with the random forest(RF)technique to predict the D_(80)value,a critical parameter in evaluating rock fragmentation quality.The study is conducted using a dataset from Sarcheshmeh Copper Mine,employing six different swarm sizes for the GWO-RF hybrid model construction.The GWO-RF model’s hyperparameters are systematically optimized within established bounds,and its performance is rigorously evaluated using multiple evaluation metrics.The results show that the GWO-RF hybrid model has higher predictive skills,exceeding traditional models in terms of accuracy.Furthermore,the interpretability of the GWO-RF model is enhanced through the utilization of SHapley Additive exPlanations(SHAP)values.The insights gained from this research contribute to optimizing blasting operations and rock fragmentation outcomes in the mining industry. 展开更多
关键词 BLASTING rock fragmentation random forest grey wolf optimization hybrid tree-based technique
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Metal-organic framework-derived porous carbon for the advanced aqueous zinc-ion hybrid capacitor
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作者 LIU Wei-fang HU Zi-han ZHANG Qi 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第7期2268-2279,共12页
Aqueous zinc ion hybrid capacitors(ZIHCs)are considered one of the most promising electrochemical energy storage systems due to their high safety,environmental friendliness,low cost,and high power density.However,the ... Aqueous zinc ion hybrid capacitors(ZIHCs)are considered one of the most promising electrochemical energy storage systems due to their high safety,environmental friendliness,low cost,and high power density.However,the low energy density and the lack of sustainable design strategies for the cathodes hinder the practical application of ZIHCs.Herein,we design the N and O co-doped porous carbon cathode by annealing metal-organic framework(ZIF-8).ZIF-8 retains the original dodecahedral structure with a high specific surface(2814.67 m^(2)/g)and I_(G)/I_(D) ratio of 1.0 during carbonization and achieves self-doping of N and O heteroatoms.Abundant defect sites are introduced into the porous carbon to provide additional active sites for ion adsorption after the activation of carbonized ZIF-8 by KOH treatment.The ZIHCs assembled with modified ZIF-8 as the cathode and commercial zinc foil as the anode show an energy density of 125 W∙h/kg and a power density of 79 W/kg.In addition,this ZIHCs device achieves capacity retention of 77.8%after 9000 electrochemical cycles,which is attributed to the diverse pore structure and plentiful defect sites of ZIF-8-800(KOH).The proposed strategy may be useful in developing high-performance metal-ion hybrid capacitors for large-scale energy storage. 展开更多
关键词 zinc ion hybrid capacitor CATHODE metal-organic framework(ZIF-8) KOH activation
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混合动力汽车能效优化与控制策略研究 被引量:1
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作者 付强 《时代汽车》 2024年第5期94-97,共4页
随着环境问题和能源危机的日益严重,混合动力汽车作为一种节能环保的交通工具,得到了广泛关注。能效优化和控制策略是混合动力汽车研究的重要方向,对于提高汽车性能、降低能耗、减少排放具有重要意义。本文旨在探讨混合动力汽车的能效... 随着环境问题和能源危机的日益严重,混合动力汽车作为一种节能环保的交通工具,得到了广泛关注。能效优化和控制策略是混合动力汽车研究的重要方向,对于提高汽车性能、降低能耗、减少排放具有重要意义。本文旨在探讨混合动力汽车的能效优化和控制策略,以提高汽车的整体性能和燃油经济性。 展开更多
关键词 混合动力汽车 能效优化 控制策略 节能环保
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A Hybrid Compensation Scheme for the Input Rate-Dependent Hysteresis of the Piezoelectric Ceramic Actuators
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作者 DONG Ruili TAN Yonghong +1 位作者 HOU Jiajia ZHENG Bangsheng 《Journal of Donghua University(English Edition)》 CAS 2024年第4期436-446,共11页
A hybrid compensation scheme for piezoelectric ceramic actuators(PEAs)is proposed.In the hybrid compensation scheme,the input rate-dependent hysteresis characteristics of the PEAs are compensated.The feedforward contr... A hybrid compensation scheme for piezoelectric ceramic actuators(PEAs)is proposed.In the hybrid compensation scheme,the input rate-dependent hysteresis characteristics of the PEAs are compensated.The feedforward controller is a novel input rate-dependent neural network hysteresis inverse model,while the feedback controller is a proportion integration differentiation(PID)controller.In the proposed inverse model,an input ratedependent auxiliary inverse operator(RAIO)and output of the hysteresis construct the expanded input space(EIS)of the inverse model which transforms the hysteresis inverse with multi-valued mapping into single-valued mapping,and the wiping-out,rate-dependent and continuous properties of the RAIO are analyzed in theories.Based on the EIS method,a hysteresis neural network inverse model,namely the dynamic back propagation neural network(DBPNN)model,is established.Moreover,a hybrid compensation scheme for the PEAs is designed to compensate for the hysteresis.Finally,the proposed method,the conventional PID controller and the hybrid controller with the modified input rate-dependent Prandtl-Ishlinskii(MRPI)model are all applied in the experimental platform.Experimental results show that the proposed method has obvious superiorities in the performance of the system. 展开更多
关键词 hybrid control input rate-dependent hysteresis inverse model neural network piezoelectric ceramic actuator
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混合误差下回归权函数估计的强相合性
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作者 潘丽静 郭鹏江 白美利 《西北大学学报(自然科学版)》 CAS CSCD 北大核心 2010年第5期756-759,共4页
目的研究混合误差下回归权函数估计的强相合性。方法讨论了-混合序列加权和的强收敛性。结果在适当的条件下,得到了混合误差下回归函数估计的强相合性。结论获得了权函数估计的大样本性质。
关键词 -混合 权函数估计 强相合
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关于—混合序列的若干强极限定理 被引量:3
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作者 唐健 汪忠志 《安徽工业大学学报(自然科学版)》 CAS 2009年第3期313-317,共5页
运用截尾的方法和三级数定理,在一定条件下研究了—混合随机变量序列的强大数定理。
关键词 -混合随机变量序列 三级数定理 强大数定理
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Experimental and CFD studies of solid-liquid slurry tank stirred with an improved Intermig impeller 被引量:12
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作者 赵洪亮 张子木 +3 位作者 张廷安 刘燕 顾松青 张超 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第8期2650-2659,共10页
The improved Intermig impeller has been used in the seed precipitation tank in China, which could enhance the mixing and suspension of Al(OH)3 particles and the power consumption declined largely. The flow field, soli... The improved Intermig impeller has been used in the seed precipitation tank in China, which could enhance the mixing and suspension of Al(OH)3 particles and the power consumption declined largely. The flow field, solids hold-up, cloud height, just off-bottom speed and power consumptions were investigated in solid-liquid mixing system with this new type of impeller by CFD and water experiment methods. Compared with the standard Intermig impeller, the improved one coupled with specially sloped baffles could promote the fluid circulation, create better solids suspension and consume less power. Besides lower impeller off-bottom clearance is good for solid suspension and distribution. The just-off-bottom speed was also determined by a power number criterion. Meanwhile, the predicted results were in good agreement with the experimental data. 展开更多
关键词 CFD stirred tank solids suspension mixing improved Intermig impeller
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Formation condition of solid solution type high-entropy alloy 被引量:22
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作者 任明星 李邦盛 傅恒志 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第4期991-995,共5页
Formation condition of high-entropy alloys with solid solution structure was investigated. Seventeen kinds of the high-entropy alloys with different components were prepared, the influencing factors (the comprehensiv... Formation condition of high-entropy alloys with solid solution structure was investigated. Seventeen kinds of the high-entropy alloys with different components were prepared, the influencing factors (the comprehensive atomic radius difference δ, the mixing enthalpy AH and the mixing entropy AS) of phase composition of the alloys were calculated, and the microstructure and phase compositions of alloys were analyzed by using SEM and XRD. The result shows that only the systems with δ≤2.77 and △H≥-8.8 kJ/mol will form high entropy alloy with simple solid solution. Otherwise, intermetallic compounds will exist in the alloys. So, selection of the type of element has important effects on microstructure and properties of high entropy alloys. 展开更多
关键词 high entropy alloy solid solution comprehensive atomic radius difference mixing enthalpy formation condition
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Experimental study of pavement performance of basalt fiber-modified asphalt mixture 被引量:17
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作者 范文孝 康海贵 郑元勋 《Journal of Southeast University(English Edition)》 EI CAS 2010年第4期614-617,共4页
To discuss the pavement performance of basalt fiber-modified asphalt mixtures,the optimum dosages of asphalt and fibers are studied by the Marshall test and the rutting test.The results demonstrate that the optimum do... To discuss the pavement performance of basalt fiber-modified asphalt mixtures,the optimum dosages of asphalt and fibers are studied by the Marshall test and the rutting test.The results demonstrate that the optimum dosages of asphalt and fibers are 4.63% and 0.3%,respectively.Then the pavement performances of basalt(polyester,xylogen)fiber-modified asphalt mixtures are investigated through high temperature stability tests,water stability tests and low temperature crack resistance tests.It indicates that the pavement performances of the fiber-modified asphalt mixtures such as rutting dynamic stability,freezing splitting tensile strength,low temperature crack resistance and so on are improved compared with control asphalt mixture.The results show that the pavement performances of asphalt mixtures can be improved by fiber-modifiers.Besides,the improvement effects of basalt fiber are superior to polyester fiber and xylogen fiber. 展开更多
关键词 asphalt mixture basalt fiber Marshall test high temperature stability test pavement performance
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ZnO Films Synthesized by Solid-Source Chemical Vapor Deposition with c-Axis Parallel to Substrate 被引量:7
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作者 吕建国 叶志镇 +2 位作者 张银珠 黄靖云 赵炳辉 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2003年第1期1-5,共5页
ZnO films with c -axis parallel to the substrate are reported.ZnO films are synthesized by solid-source chemical vapor deposition,a novel CVD technique,using zinc acetate dihydrate (solid) as the source material.The p... ZnO films with c -axis parallel to the substrate are reported.ZnO films are synthesized by solid-source chemical vapor deposition,a novel CVD technique,using zinc acetate dihydrate (solid) as the source material.The properties are characterized by X-ray diffraction,atomic force microscopy and transmission spectra.The parallel oriented ZnO films with mixed orientation for (100) and (110) planes are achieved on glass at the substrate temperature of 200℃ and the source temperature of 280℃,and a qualitative explanation is given for the forming of the mixed orientation.AFM images show that the surface is somewhat rough for the parallel oriented ZnO films.The transmission spectrum exhibits a high transmittance of about 85% in the visible region and shows an optical band gap about 3.25eV at room temperature. 展开更多
关键词 ZnO films SS-CVD mixed orientation c -axis parallel to the substrate
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Hot corrosion behavior of Ni–16Cr–xAl based alloys in mixture of Na_2SO_4-NaCl at 600 ℃ 被引量:4
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作者 李维杰 刘咏 +2 位作者 王岩 韩朝 汤慧萍 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第12期2617-2625,共9页
The hot corrosion behaviors of Ni–16Cr–xAl(x=4.5%, 6.8%, 9.0%, mass fraction) based alloys in Na2SO4–25% NaCl molten salts at 600 °C were investigated. The effects of pre-oxidation and Al content on the resi... The hot corrosion behaviors of Ni–16Cr–xAl(x=4.5%, 6.8%, 9.0%, mass fraction) based alloys in Na2SO4–25% NaCl molten salts at 600 °C were investigated. The effects of pre-oxidation and Al content on the resistance to hot corrosion were examined. The hot corrosion resistance of Ni–16Cr–xAl based alloy with Al addition from 4.5% to 9.0% increases with increasing Al content. The alloy with Al content of 9.0% shows the highest hot corrosion resistance among the examined alloys because more β–NiAl phases are obtained to sustain the Al2O3 scale repaired during hot corrosion. Pre-oxidized specimens have a superior hot corrosion resistance compared with the as-cast specimens, due to a protective oxide scale formed after pre-treatment. 展开更多
关键词 Ni–16Cr–xAl based alloys PRE-OXIDATION Na2SO4–25% NaCl mixed salt hot-corrosion mechanism
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Radial mixing and segregation of granular bed bi-dispersed both in particle size and density within horizontal rotating drum 被引量:3
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作者 陈辉 赵先琼 +2 位作者 肖友刚 刘义伦 刘颖 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第2期527-535,共9页
Taking simultaneous variations in both particle volume and density into account, the radial mixing and segregation of binary granular bed in a rotating drum half loaded were investigated by a 3D discrete element metho... Taking simultaneous variations in both particle volume and density into account, the radial mixing and segregation of binary granular bed in a rotating drum half loaded were investigated by a 3D discrete element method. Then, based on the competition theory of condensation and percolation, radial segregation due to differences in particle volume and/or density was analyzed. The results show that if either percolation effect induced by volume difference or condensation effect induced by density difference dominates in the active layer of moving bed, separation will occur. Controlling the volume ratio or density ratio of the two types of particles can achieve an equilibrium state between percolation and condensation, and then homogenous mixture can be obtained. When the percolation balances with the condensation, the relationship between volume ratioand density ratiopresents nearly a power function. Scaling up a rotating drum will not affect the mixing degree of the granular bed so long as the volume ratio and density ratio are predefined. 展开更多
关键词 binary granular bed rotating drum solid particle radial mixing SEGREGATION discrete element method
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16-Channel 0.35μm CMOS/VCSEL Transmission Modules 被引量:3
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作者 陈弘达 申荣铉 +9 位作者 毛陆虹 唐君 梁琨 杜云 黄永箴 吴荣汉 冯军 柯锡明 刘欢艳 王志功 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2003年第3期245-249,共5页
The vertical cavity surface emitting laser (VCSEL) arrays and VCSEL-based optical transmission modules are investigated.It includes the VCSEL's spectral characteristic,modulation characteristic,high frequency char... The vertical cavity surface emitting laser (VCSEL) arrays and VCSEL-based optical transmission modules are investigated.It includes the VCSEL's spectral characteristic,modulation characteristic,high frequency characteristic,and compatibility with microelectronic circuit.The module consists of 1×16 VCSEL array and 16-channel lasers driver with 0.35μm CMOS circuit by hybrid integration.During the test process,the module operates well at more than 2GHz in -3dB frequency bandwidth. 展开更多
关键词 VCSEL CMOS optoelectronic integration optical interconnects
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SO_2 emission characteristics from co-firing of petroleum coke and coal in circulating fluidized bed 被引量:2
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作者 赵长遂 王文选 +2 位作者 王凤君 陈传敏 韩松 《Journal of Southeast University(English Edition)》 EI CAS 2005年第1期48-52,共5页
Combustion and sulfur retention experiments of mixed fuel of petroleum cokeand coal were conducted on a pilot-scale circulating fluidized bed (CFB) combustor with the thermalinput of 0. 6 MW. The effects of several pa... Combustion and sulfur retention experiments of mixed fuel of petroleum cokeand coal were conducted on a pilot-scale circulating fluidized bed (CFB) combustor with the thermalinput of 0. 6 MW. The effects of several parameters, such as the primary air percentage, excess aircoefficient, bed temperature, Ca/S molar ratio and mass ratio of petroleum coke to coal on SO_2emission were verified. Experimental results show that when the ratio of petroleum coke to coal inthe mixed fuel increases, the SO_2emission increases. The maximum SO_2 emission appears when purecoke burns. The SO_2 concentration in flue gas reduces with the increase in the primary airpercentage, excess air coefficient and Ca/S molar ratio for all kinds of fuel mixtures. Therangebetween 830 t and 850 t is the optimal temperature for sulfur retention during co-firing ofpetroleum coke and coal with the mass ratio R of 1 and 3 in CFB. 展开更多
关键词 circulating fluidized bed petroleum coke COAL CO-FIRING DESULFURIZATION
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Axle-equivalent method of steel-deck pavement 被引量:3
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作者 张磊 钱振东 +1 位作者 程刚 刘振清 《Journal of Southeast University(English Edition)》 EI CAS 2006年第1期96-100,共5页
An index system of steel deck pavement design is proposed according to the study and classification of failure types. Furthermore the axle-equivalent equation is presented according to the fatigue principle of pavemen... An index system of steel deck pavement design is proposed according to the study and classification of failure types. Furthermore the axle-equivalent equation is presented according to the fatigue principle of pavement structures. Based on indoor experiments and theoretical analysis, this paper studies the stress characteristics of three different axle types which are corresponding with the other three typical pavement structures, and also presents the parameters of each axle's equivalent formula. The three axle types include single-axle single-wheel, single-axle double-wheel and double-axle double-wheel. According to analyses of influential factors such as climate, environment, traffic and stress condition, the developed axle equivalent formula and the parameters modified by the field test data can be applied in the design of a new bridge deck pavement and the assessment of an existing bridge deck pavement. 展开更多
关键词 steel bridge asphalt mixture PAVEMENT fatigue-equivalent principle axle-equivalent method INDEX
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Identification and Pathogen Characteristics Analysis of a Co-infection with CSFV,PRRSV and PCV2 被引量:2
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作者 吴锦艳 田宏 +6 位作者 尚佑军 王光祥 靳野 尹双辉 陈研 何建辉 刘湘涛 《Agricultural Science & Technology》 CAS 2010年第2期19-22,108,共5页
[Objective] The aim of this study was to identify swine diseases caused by CSFV,PRRSV and PCV2 and thus to analyze its pathogeny chracteristics.[Method] The tissues and viscera of the diseased swine were collected fro... [Objective] The aim of this study was to identify swine diseases caused by CSFV,PRRSV and PCV2 and thus to analyze its pathogeny chracteristics.[Method] The tissues and viscera of the diseased swine were collected from Xiangtan of Hunan(Code of HN/XT)to extract DNA and RNA for PCR amplification and sequencing.Meanwhile,the virulent strains were isolated and identified by cell separation technology.[Result] The sequencing analysis results showed that the amino acid homology between CSFV,PRRSV,PCV2 and sequen... 展开更多
关键词 Xiangtan of Hunan Porcine disease CO-INFECTION IDENTIFICATION Pathogeny characteristics
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