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Methods for separating the noise produced by the wheels and track during a train pass‑by
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作者 David Thompson Dong Zhao +4 位作者 Giacomo Squicciarini Martin Toward Ester Cierco Erwin Jansen Michael Dittrich 《Railway Engineering Science》 2025年第3期342-358,共17页
Rolling noise is produced by vibration of the wheels and track,induced by their combined surface roughness.It is important to know the relative contributions of the different sources,as this affects noise control stra... Rolling noise is produced by vibration of the wheels and track,induced by their combined surface roughness.It is important to know the relative contributions of the different sources,as this affects noise control strategies as well as acceptance testing of new rolling stock.Three different techniques are described that aim to use pass-by measurements to separate the wheel and track components of rolling noise.One is based on the TWINS model,which is tuned to measured track vibration.The second is based on the advanced transfer path analysis method,which provides an entirely experimental assessment.The third is based on the pass-by analysis method in combination with static vibroacoustic transfer functions which are obtained using a reciprocity method.The development of these methods is described and comparisons between them are presented using the results from three experimental measurement campaigns.These covered a metro train,a regional train and a high-speed train at a range of speeds.The various methods agree reasonably well in terms of overall trends,with moderate agreement in the mid-frequency region,and less consistent results at low and high frequency. 展开更多
关键词 Railway noise Rolling noise Source separation Pass-by tests
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A new method for separating complex touching equiaxed and lamellar alpha phases in microstructure of titanium alloy 被引量:1
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作者 吉喆 杨合 +1 位作者 李宏伟 樊晓光 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第8期2265-2269,共5页
A new method for separating complex touching equiaxed and lamellar alpha phases in the optical micrograph of titanium alloy was proposed for quantitative characterization. This new method involves three steps. First, ... A new method for separating complex touching equiaxed and lamellar alpha phases in the optical micrograph of titanium alloy was proposed for quantitative characterization. This new method involves three steps. First, concave points of the microstructural feature are identified with a threshold of the concaveness of the comer points which are extracted from the binarized image. Secondly, concave points pairs are selected from the concave points group established by means of marker circle or distance. Third, whether a candidate separation line which connects two concave points within a pair can be accepted or not is determined by the proposed four rules. The obtained results show that this method is effective on separating complex touching microstructural features. 展开更多
关键词 titanium alloy microstructural feature separation method
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Comparison of coal separation characteristics based on different separating approaches in dry coal beneficiation flowsheet 被引量:2
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作者 贺靖峰 赵跃民 +2 位作者 何亚群 骆振福 段晨龙 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第5期1651-1659,共9页
The separation characteristic of raw coal from Luoyang mining area, China, was investigated by applying a dry coal beneficiation flowsheet with the dense medium gas-solid fluidized bed as main separating equipment. Th... The separation characteristic of raw coal from Luoyang mining area, China, was investigated by applying a dry coal beneficiation flowsheet with the dense medium gas-solid fluidized bed as main separating equipment. The experimental and simulation results indicate that the dense medium gas-solid fluidized bed can provide uniform distribution and stable fluctuation of bed densities at various heights. Two types of different separating approaches were compared using the dry coal beneficiation flowsheet. Compared with obtaining cleaning coal in the first stage of the flowsheet, a higher yield of the cleaning coal and better separation efficiency can be achieved when discharging gangue in the first stage. Finally, the results indicate that 64.86% pure cleaning coal with an ash content of 11.77% and 13.53% middlings were obtained, and 21.61% gangue was removed in two successive separation stages with the probable errors of 0.05 and 0.07 g/cm3, respectively. 展开更多
关键词 separation characteristic dense medium gas-solid fluidized bed separating approach numerical simulation density stability
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Failure analysis of wear of main clutch separating ring of heavy vehicles 被引量:1
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作者 孙晓龙 李晓延 +1 位作者 朱有利 徐滨士 《Journal of Central South University》 SCIE EI CAS 2005年第S2期124-128,共5页
The severe wear of separating ring is considered to be a main reason which leads to the improper declutch of the main clutch of heavy vehicles. The wear mechanism of the separating ring is not well understood. Scannin... The severe wear of separating ring is considered to be a main reason which leads to the improper declutch of the main clutch of heavy vehicles. The wear mechanism of the separating ring is not well understood. Scanning electron microscopy and transmission electron microscopy were employed to analyze the surface features and dislocation characteristics of the separating ring. The typical features of furrows and rolled tongue-like metal were found on the surface of separating ring by scanning electron microscopy observation, which can be considered as a major indication of the grain-abrasion. A zone of high density dislocation was noted on the subsurface of the separating ring by transmission electron microscopy observation, which implies the contribution of the severe impact on the surface of the separating ring in the wear process. The influences of the structure of the separating ring, the service condition and the in-service stress distribution on the wear behavior, were also analyzed. The results show that the failure of separating ring results from the impact wear and grain-abrasion together with the plastic deformation. 展开更多
关键词 separating RING FAILURE analysis ABRASIVE WEAR IMPACT WEAR
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Three-dimensional numerical simulation of flow and splash behavior in an oxygen coal combustion melting and separating furnace 被引量:1
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作者 Kai Zhao Yao-zong Shen +6 位作者 Zheng Kong Qiao-rong Zhang Yu-zhu Zhang Yan Shi Chang-liang Zhen Xue-feng Shi Xing-hua Zhang 《Journal of Iron and Steel Research International》 SCIE EI CSCD 2021年第8期965-977,共13页
The change of bubbles and the position of the tuyere in an oxygen coal combustion melting and separating furnace affect the flow and splash behavior of the molten pool.To analyze this problem further,a three-dimension... The change of bubbles and the position of the tuyere in an oxygen coal combustion melting and separating furnace affect the flow and splash behavior of the molten pool.To analyze this problem further,a three-dimensional numerical simulation method was used to explore the behavior and change of the flow field inside the molten pool during double-row tuyere injection.In addition,the arrangement of the tuyere was changed for a more detailed understanding of the internal phase distribution and splashing in a molten pool.The results indicated that under three-dimensional numerical simulation conditions,bubbles rise after leaving the tuyere and break on the surface of the molten pool,which results in certain fluctuations in the nearby melt.During the injection process of the tuyere,the meteorological accumulation in the middle part of the molten pool formed part of the foam slag because of the influence of surface tension.When the layout of the upper and lower exhaust tuyeres was changed from staggered to symmetrical,or when the spacing of the upper and lower exhaust tuyeres changed,it had an effect on the phase distribution and splash behavior. 展开更多
关键词 Oxygen coal combustion melting and separating furnace Exhaust tuyere Phase distribution SPLASH Numerical simulation
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A new combination process of distillation with salt extraction for separating organic solvent-water azeotropes
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作者 潘晓梅 肖国民 杨志才 《Journal of Southeast University(English Edition)》 EI CAS 2004年第2期226-228,共3页
A novel process which can purify the organic solvents from their azeotropes with water is proposed. In this process,water can be drained off both from bottom and overhead of tower at the same time,and the organic solv... A novel process which can purify the organic solvents from their azeotropes with water is proposed. In this process,water can be drained off both from bottom and overhead of tower at the same time,and the organic solvent is concentrated in the tower and accumulated in the middle vessel at last. So the progress is time-shortened and energy-saving. The product purity is 99. 8% and the product yield is more than 99.5%. Simulation of liquid-liquid equilibrium (LLE) and the equipment operation data agree well with the experiment. 展开更多
关键词 AZEOTROPE SEPARATION bath distillation salt extraction
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SEPARATING BROWN AND BLACK BEARS IN NORTHEAST CHINA USING TOOTH MEASUREMENTS
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作者 姜兆文 郑红 +1 位作者 王玉玺 张淑云 《Journal of Northeast Forestry University》 SCIE CAS CSCD 1995年第2期58-60,共3页
An expeditious method for ascertaining species between black bear (Selenarctos thibetanus G. cuiver) and brown bear (Ursus arctos Linnaeus) was developed using tooth measurements from previously identified specimens. ... An expeditious method for ascertaining species between black bear (Selenarctos thibetanus G. cuiver) and brown bear (Ursus arctos Linnaeus) was developed using tooth measurements from previously identified specimens. The measurement and analysis on 18 tooth measurement indexes (i.e. T1. Length of Pm1-Pm4, T2. L. of M1-M3, T3. M1L., T4. M1 width, T5. M2L., T6. M2W., T7.M3L., T8. M3W., T9. L. of C1 alveolus, T10. W. of C1 alveolus, T11. L. of C1-M2, T12. L. of Pm4 M2,T13.M1L., T14. M1W., T15. M2L., T16. M2W., T17.L. of C1 alveolus, T18. W. of C1 alveolus) of 59 skulls (black bears 25, brown bears 34) indicates that there are significant or the most significant difference between two species in every indexes, however T1, T9, T10, T17 and T18 are not suitable for species discriminator because of their high percent of overlap. The efficient species discriminators and standards (mm) are as follows T2(63.0), T3(22.0), T4(10.2), T5(23.8), T6(13.6), T7(18.0), T8(13.5), T11(110.0),T12(66.0), T13(20. 1), T14(15.8), T15(33.0) and T16(17.3). Those who are less than or equal to standard are classified to black bear, the others are brown bear. The method is very convenient and useful with high reliability. Their lowest accuracy percent are 95.0%, most of them over 97%. Different indexes will be chosen refer to the degree of specimen destroyed. 展开更多
关键词 BLACK BEAR (Selenarctos thibetanus) BROWN BEAR (Ursus arctos) TOOTH measurement separating
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Study on influencing factors of adapters separating with the underwater missile
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作者 傅德彬 牛青林 +1 位作者 刘小军 李霞 《Journal of Beijing Institute of Technology》 EI CAS 2015年第2期158-163,共6页
To analyze main factors affecting the separation reliability between a missile and adapters for the launching process, a six DOF underwater dynamic model for the missile and adapters is utilized to simulate the separa... To analyze main factors affecting the separation reliability between a missile and adapters for the launching process, a six DOF underwater dynamic model for the missile and adapters is utilized to simulate the separation process, considering elastic forces of separating springs, hydrodynamic forces, gravity and buoyancy. Moreover, a criterion based on the maximum separating distance is put forward to determine whether adapters separate with the missile reliably. The results show that the magnitude and position of elastic force, the wedge angle and mass of the adapter significantly affect the separating process. The local sensitivity analysis for the reference status of design parameters demonstrates that the wedge angle of adapters has the maximum influence about 70. 4% on the separating distance. 展开更多
关键词 ADAPTER hydrodynamic force separating spring reliability criterion
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SUPPORTING AND SEPARATING SUBSETS FOR INVEX BODIES
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作者 H.K.El-Sayied 《Acta Mathematica Scientia》 SCIE CSCD 2008年第4期818-822,共5页
Invex bodies represent an important class of bodies which are considered as a generalization of convex bodies.In this article,the author studies the supporting for this class of bodies as well as the separating subset... Invex bodies represent an important class of bodies which are considered as a generalization of convex bodies.In this article,the author studies the supporting for this class of bodies as well as the separating subsets of two bodies. 展开更多
关键词 Invex bodies focal points-supporting separating
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Some discussions about method for solving the variable separating nonlinear models
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作者 阮航宇 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第5期17-24,共8页
Through analysing the exact solution of some nonlinear models, the role of the variable separating method in solving nonlinear equations is discussed. We find that rich solution structures of some special fields of th... Through analysing the exact solution of some nonlinear models, the role of the variable separating method in solving nonlinear equations is discussed. We find that rich solution structures of some special fields of these equations come from the nonzero seed solution. However, these nonzero seed solutions is likely to result in the divergent phenomena for the other field component of the same equation. The convergence and the signification of all field components should be discussed when someone solves the nonlinear equation using the variable separating method. 展开更多
关键词 variable separating method nonzero seed solution nonlinear equation
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Application of the Separating Theorem
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作者 王治国 《Chinese Quarterly Journal of Mathematics》 CSCD 1999年第3期103-104, ,共2页
This thesis discusses the theory of nonlinear programming (NLP) including the maths solution to a type of inequality of convex function by utilizing the separating Theorem.
关键词 separating Theorem APPLICATION
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Separating trash and solid materials from the wastewater ammonia stripping tower UASB biological oxidation pond processes for the treatment of the swine factory's wastewater
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作者 LU Xiu-guo ZHANG Pan RAO Ting LIU Yan 《Journal of Environmental Science and Engineering》 2009年第3期12-16,共5页
By making the use of the processes which includes separating trash and solid materials from the wastewater-ammonia stripping tower-UASB-biological oxidation pond, we have treated the wastewater which comes from the sw... By making the use of the processes which includes separating trash and solid materials from the wastewater-ammonia stripping tower-UASB-biological oxidation pond, we have treated the wastewater which comes from the swine factory. The treated wastewater can meet the primary standard of The People's Republic of China based on sewage discharge standards and the wastewater treatment project design contract (GBl8596-2001), and the effluent will be used as irrigation-water. We introduce this project including the quality of influent and effluent and the flow scheme, the statement of every part, the investment and the effect, etc. The operation indicated that this process has many merits such as the stability in operation-effect and the convenience in management. So it will provide some help for the similar wastewater treatment. 展开更多
关键词 separating trash and solid materials from wastewater ammonia stripping UASB biological oxidation pond the swine factory's wastewater
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Research on Separating Overlapped Explosion Recordings
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作者 Yang Xuanhui, Shen Ping, and Dong TingCenter for Seismic Data and Information, CSB, Beijing 100045, China Institute of Geophysics, CSB, Beijing 100081, China 《Earthquake Research in China》 1999年第1期27-34,共8页
By using wavelet analysis and the co-deduct method, under the condition that two explosions are supposed to have the same mechanism and strength, we separated the overlapped recordings successfully.
关键词 WAVELET analysis separating Overlapped RECORDING Co-deduct method.
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Equivalent Separating Curves on Surfaces and Its Applications to Haken Spheres
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作者 沈广艳 雷逢春 廖公夫 《Northeastern Mathematical Journal》 CSCD 2005年第1期1-4,共4页
1 Introduction Let A be a collection of n pairwise disjoint simple closed curves on an orientable closed surface F of genus n ≥2. We say that A is a complete system of F if the surface obtained by cutting F along A i... 1 Introduction Let A be a collection of n pairwise disjoint simple closed curves on an orientable closed surface F of genus n ≥2. We say that A is a complete system of F if the surface obtained by cutting F along A is a 2n-punctured sphere. Let A1, A2 be two non-empty subsets of A. We say that (A1,A2) is a partition of A if A1 ∩A2 = (?) and A1 ∪A2 = A. Let (A1, A2) be a partition of A on F, and C a simple closed curve on F. We say that C is separating with respect to (A1, A2) if it is disjoint from A and it cuts F into two pieces F1,F2 with A1(?) F1,A2 (?) F2. 展开更多
关键词 separating curve with respect to a partition Haken sphere weakly equivalent Haken sphere
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Equivalent Separating Curves on Closed Surface of Genus 2
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作者 沈广艳 雷逢春 《Northeastern Mathematical Journal》 CSCD 2006年第2期193-198,共6页
Let {A, B} be a complete system of the closed orientable surface F of genus 2. A simple closed curve C on F is separating with respect to (A, B) if it is disjoint from A U B and it cuts F into two once-punctured tor... Let {A, B} be a complete system of the closed orientable surface F of genus 2. A simple closed curve C on F is separating with respect to (A, B) if it is disjoint from A U B and it cuts F into two once-punctured tori X, Y with A belong X, B belong Y. Let γ be a simple closed curve on F which is disjoint from A ∪ B and intersects C essentially in two points. In this paper, we show that up to isotopy, {hγ^n(C) : n ∈ Z} is the set containing all the simple closed curves on F which is separating with respect to (A, B), where hγ is the Dehn twist along γ on F. This also shows how two simple closed curves on F which are separating with respect to (A, B) are related. The result can be applied to yield all Haken spheres of a Heegaard splitting V∪F W which are weakly equivalent to a given Heken sphere of the splitting. 展开更多
关键词 separating curve with respect to a partition Dehn twist Haken sphere 1991 MR subject classification 57M
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First membrane unit for separating CO_2 from natural gas operational
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《Bulletin of the Chinese Academy of Sciences》 2007年第1期57-57,共1页
After a more-than-two-week trial operation, a new membrane unit based on the technology developed by researchers from the CAS Dalian Institute of
关键词 CO First membrane unit for separating CO2 from natural gas operational
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Development course of separating rare earths with acid phosphorus extractants: A critical review 被引量:28
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作者 Deqian Li 《Journal of Rare Earths》 SCIE EI CAS CSCD 2019年第5期468-486,共19页
This paper reviews the development course of separating rare earths with acid phosphorus extractants,including extraction chemistry(thermodynamics and kinetics), separation process and industrial application, the loss... This paper reviews the development course of separating rare earths with acid phosphorus extractants,including extraction chemistry(thermodynamics and kinetics), separation process and industrial application, the loss/degradation of extractants, etc. 展开更多
关键词 RARE earths ACID PHOSPHORUS EXTRACTANTS Extraction chemistry Separation process Loss/Degradation of EXTRACTANTS
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Numerical Simulation of Separating Gas Mixtures via Hydrate Formation in Bubble Column 被引量:7
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作者 罗艳托 朱建华 陈光进 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第3期345-352,共8页
To develop a new technique for separating gas mixtures via hydrate formation,a set of medium-sized experimental bubble column reactor equipment was constructed.On the basis of the structure parameters of the ex- perim... To develop a new technique for separating gas mixtures via hydrate formation,a set of medium-sized experimental bubble column reactor equipment was constructed.On the basis of the structure parameters of the ex- perimental bubble column reactor,assuming that the liquid phase was in the axial dispersion regime and the gas phase was in the plug flow regime,in the presence of hydrate promoter tetrahydrofuran(THF),the rate of hydrogen enrichment for CH4+H2 gas mixtures at different operational conditions(such as temperature,pressure,concentra- tion of gas components,gas flow rate,liquid flow rate)were simulated.The heat product of the hydrate reaction and its axial distribution under different operational conditions were also calculated.The results would be helpful not only to setting and optimizing operation conditions and design of multi-refrigeration equipment,but also to hydrate separation technique industrialization. 展开更多
关键词 HYDRATE KINETICS SEPARATION bubble column numerical simulation
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Separating and imaging diffractions in dip domain on the basis of slope analysis 被引量:3
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作者 Kong Xue Wang De-Ying +2 位作者 Li Zhen-Chun Zhang Rui-Xiang Hu Qiu-Yuan 《Applied Geophysics》 SCIE CSCD 2020年第1期103-110,169,共9页
Fracture-cave reservoirs in carbonate rocks are characterized by a large difference in fracture and cavity size,and a sharp variation in lithology and velocity,thereby resulting in complex diffraction responses.Some s... Fracture-cave reservoirs in carbonate rocks are characterized by a large difference in fracture and cavity size,and a sharp variation in lithology and velocity,thereby resulting in complex diffraction responses.Some small-scale fractures and caves cause weak diffraction energy and would be obscured by the continuous reflection layer in the imaging section,thereby making them difficult to identify.This paper develops a diffraction wave imaging method in the dip domain,which can improve the resolution of small-scale diffractors in the imaging section.Common imaging gathers(CIGs)in the dip domain are extracted by Gaussian beam migration.In accordance with the geometric differences of the diffraction being quasilinear and the reflection being quasiparabolic in the dip-domain CIGs,we use slope analysis technique to filter waves and use Hanning window function to improve the diffraction wave separation level.The diffraction dip-domain CIGs are stacked horizontally to obtain diffraction imaging results.Wavefield separation analysis and numerical modeling results show that the slope analysis method,together with Hanning window filtering,can better suppress noise to obtain the diffraction dip-domain CIGs,thereby improving the clarity of the diffractors in the diffraction imaging section. 展开更多
关键词 dip domain wavefield separation diffraction imaging
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Flotation Separating Rutile from Calcium and Silicon Gangue Minerals 被引量:1
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作者 Hao Ding1, HaiLin 2 1) Beijing Academy of Building Materials, Beijing 100041, China 2) University of Science and Technology Beijing, Beijing 100083, China 《Rare Metals》 SCIE EI CAS CSCD 2001年第4期205-208,共4页
Rutile separation from calcite, apatite and quartz by flotation was investigated. The results show that the rutile separation from calcium and silicon gangue minerals can be realized with alkyl-imino-bismethylene phos... Rutile separation from calcite, apatite and quartz by flotation was investigated. The results show that the rutile separation from calcium and silicon gangue minerals can be realized with alkyl-imino-bismethylene phosphoric acid (TF112) as a collector and sodium hexametaphosphate (SH) as a regulator. 展开更多
关键词 RUTILE calcium and silicon gangue minerals FLOTATION separate alkyl-imino-bismethylene phosphoric acid sodium hexametaphosphate
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