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Semi-Automatic Modeling Technique of Torque Converter Flow Passage 被引量:3
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作者 Shiping Liu Shujuan Zheng 《Modern Mechanical Engineering》 2013年第2期59-68,共10页
The modeling technique of hydrodynamic torque converter flow passage was investigated. The semi-automatic modeling technique of torque converter flow passage was proposed. The flow passage model of each converter whee... The modeling technique of hydrodynamic torque converter flow passage was investigated. The semi-automatic modeling technique of torque converter flow passage was proposed. The flow passage model of each converter wheel is considered as a revolution entity sliced by two curved surfaces. In order to generate the revolution entity, a new approximation method, condition optimum arc approximation, was proposed. The method was used to approximate the meridional streamlines of the inner and outer wall. As a result, the three-dimensional revolution entity can be conveniently generated. In order to create slice surfaces, the central stream surface of flow passage was approximated with a quadric surface. The normal vector of the quadric surface and the thickness/thickness-function of bade were used to calculate the discrete point coordinates of blade surfaces. Via the rotation transformation to the coordinates, the discrete point coordinates of slice surfaces were obtained. A parameterized program code used for the hydrodynamic torque converter design and semi-automatic modeling was developed. Modeling errors were calculated and analyzed. The flow passage model was generated in several minutes with the help of the program code, Auto CAD and Solidworks software. Finally, the model was inputted into Gambit, and the pre-processing task used for the numerical simulation of torque converter flow field was successfully completed. The investigation results show that the semi-automatic modeling not only can ensure the accuracy of modeling, but also librates the research and design workers of torque converter from the time-consuming modeling work, which paves the way for the numerical simulation of the complex flow field of the hydrodynamic torque converter. 展开更多
关键词 HYDRODYNAMIC TORQUE Converter Flow Field Simulation semi-automatic Modeling QUADRIC Surface Condition OPTIMUM APPROXIMATION
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Soil Mapping of a Small Watershed in a Brazilian Savanna Biome: A Semi-Automatic Approach
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作者 Larissa Ane de Sousa Lima Adriana Reatto Henrique Llacer Roig 《Journal of Geographic Information System》 2014年第2期79-87,共9页
The objective of this work is to propose a semi-automatic methodology for the creation of a semidetailed to detailed watershed’s soil map. This methodological proposal is based on the traditional method (field work a... The objective of this work is to propose a semi-automatic methodology for the creation of a semidetailed to detailed watershed’s soil map. This methodological proposal is based on the traditional method (field work and photo interpretation) and on morphometric variables analysis, using data originated from the Digital Elevation Model (DEM) of the Shuttle Radar Topography Mission (SRTM) program. The steps taken through this methodological proposal were the identification of the hydromorphic areas boundaries through interpretation of aerial orthophotographs;the compartmentalization of the relief through color composition techniques using the morphometric variables—slope, altimetry and horizontal curvature;the development of a pedological database based on data gathered in the field;the elaboration of a preliminary soil map based on the compartmentalized relief and on the dataset of the soils sampled in the field;the elaboration and adjustment of the final soil map according to the interpretation of aerial photographs and also the physical and chemical analyses of the soils. This semi-automatic methodology demonstrated improved efficiency in defining the soil units, reducing operation time and subjectivity of the process, thereby contributing to the systematization of soil mapping at watershed level in scale 1:50,000, as well as, promoting better knowledge between the relation of the geomorphic and soil variables in the Brazilian Savanna Cerrado. 展开更多
关键词 semi-automatic MAPPING SRTM MORPHOMETRIC Pedological MAPS
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Integration of User-system View for Cyber Crime Analysis: A Semi-automatic Approach
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作者 K.P. Chow Erica S.L. Ho +5 位作者 Lucas C.K. Hui S.M. Yiu Tom Y.M. Lai R.S. Xu Y Mai Xiaoxi Fan 《中国司法鉴定》 2012年第5期50-58,共9页
There is a rapid rise in cybercrime cases. There does not exist any effective forensic methods to deal with these eybercrime cases. Investigators are required to study the details of a large amount of tedious source i... There is a rapid rise in cybercrime cases. There does not exist any effective forensic methods to deal with these eybercrime cases. Investigators are required to study the details of a large amount of tedious source in order to understand the crime model and dig out the evidence. This requires a lot of effort and may result in human errors. In order to overcome these potential errors that may cause by the investigators, we propose a semi-automatic approach that integrates the user view (based on a high level study of the forensic investigator) and the system view (based on the automatic analysis of the source codes) to assist investigators in refining the scope of the investigation. The approach has been verified using a real cybercrime case and the method has been shown to be effective in assisting the investigators in refining the scope of investigation and understanding the crime model. The semi-automatic approach has improved the efficiency and reliability of the digital forensic analysis of cybercrime cases involving large volume of digital evidence from multiple sources. 展开更多
关键词 CYBERCRIME ANALYSIS forensic methodology semi-automatic APPROACH
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A Semi-automatic Method Based on Statistic for Mandarin Semantic Structures Extraction in Specific Domains 被引量:1
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作者 熊英 朱杰 孙静 《Journal of Shanghai Jiaotong university(Science)》 EI 2004年第4期25-29,共5页
This paper proposed a new method of semi-automatic extraction for semantic structures from unlabelled corpora in specific domains. The approach is statistical in nature. The extracted structures can be used for shallo... This paper proposed a new method of semi-automatic extraction for semantic structures from unlabelled corpora in specific domains. The approach is statistical in nature. The extracted structures can be used for shallow parsing and semantic labeling. By iteratively extracting new words and clustering words, we get an inital semantic lexicon that groups words of the same semantic meaning together as a class. After that, a bootstrapping algorithm is adopted to extract semantic structures. Then the semantic structures are used to extract new 展开更多
关键词 and augment the semantic lexicon. The resultant semantic structures are interpreted by persons and are amenable to hand-editing for refinement. In this experiment the semi-automatically extracted structures S SA provide recall rate of 84.
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An Analysis of the Orthogonal Crank-rocking Lever Spatial Mechanism for the Weft Insertion in Rapier Looms 被引量:6
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作者 Li Kerang(李克让) +1 位作者 Chen Ming(陈明) 《Journal of Donghua University(English Edition)》 EI CAS 2001年第1期27-31,共5页
On the basis of the analysis of typical orthogonal crankrocking lever spatial mechanism for the weft insertion in rapier looms, the rules of the outputting lever motion and the mechanism pressure-angle variety are stu... On the basis of the analysis of typical orthogonal crankrocking lever spatial mechanism for the weft insertion in rapier looms, the rules of the outputting lever motion and the mechanism pressure-angle variety are studied when the maximum swing angle of rocking lever and the length of outputting lever have different values, and the optimum parameters suitable for motion transmission can be chosen. At the same time some existing shortpoints of the mechanism are also pointed out. 展开更多
关键词 RAPIER loom WEFT INSERTION mechanism motion transmission performance.
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CONJUGATE CAM WITH FIVE-BAR LINKAGE MECHANISM FOR RAPIER DRIVE OF FLEXIBLE RAPIER LOOMS 被引量:2
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作者 张建 毕丽蕴 《Journal of China Textile University(English Edition)》 EI CAS 1997年第4期71-75,共5页
A new type of rapier drive for flexible rapier loom through conjugate cams with five-bar linkage mechanism is raised and analyzed. Two designs suitable for the conversion of 1515-190.5 shuttle looms are given as examp... A new type of rapier drive for flexible rapier loom through conjugate cams with five-bar linkage mechanism is raised and analyzed. Two designs suitable for the conversion of 1515-190.5 shuttle looms are given as examples. This mechanism can be applied to traditional shuttle looms as well as to new flexible rapier loom design. 展开更多
关键词 RAPIER loom CONJUGATE CAM LINKAGE mechanism
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Air Velocity Fluctuation in Reed Groove of Air-Jet Loom 被引量:2
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作者 魏孟媛 薛文良 +2 位作者 陆维民 陈革 祝章琛 《Journal of Donghua University(English Edition)》 EI CAS 2011年第2期170-176,共7页
The airflow in the reed groove of the air jet loom for the weft insertion includes the jet stream from the relay nozzle, the back leak stream from the reed, and the diffusion stream from the open side. The air velocit... The airflow in the reed groove of the air jet loom for the weft insertion includes the jet stream from the relay nozzle, the back leak stream from the reed, and the diffusion stream from the open side. The air velocity in the reed groove can be measured to analyze the influence of process parameters during the weft insertion. The relation between the air velocity and the relay nozzle distance, the jet angle or the supply pressure of the relay nozzle can be studied. In this paper, the pitot tube is applied to measure the air velocity in reed groove by the instrument designed. And the results indicate that the air velocity fluctuation in the reed groove is strong, and can drop from 150 m·s-1 to 80 m·s-1 drastically. 展开更多
关键词 air-jet loom reed groove airflow state relay nozzle weft insertion
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MODIFIED MOTION PATTERN OF LOOM RAPIER
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作者 道德锟 《Journal of China Textile University(English Edition)》 EI CAS 1993年第2期20-28,共9页
A modified trapezoid acceleration pattern with a constant speed part is introduced for loomrapier motion driven by cam.The pattern can meet the time requirement of rapier on entering andleaving the shed,and can satisf... A modified trapezoid acceleration pattern with a constant speed part is introduced for loomrapier motion driven by cam.The pattern can meet the time requirement of rapier on entering andleaving the shed,and can satisfy the condition when the period duration of inserting is not equal tothat of withdrawing.Meanwhile,the pattern can also reduce the maximum acceleration of rapierand make the derivatives of rapier acceleration change continuously without any abruptness ofjerks. 展开更多
关键词 cam looms RAPIER loom CONSTANT speed MODIFIED TRAPEZOID ACCELERATION
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RECONSTRUCTION OF AXLE-TREADLE LOOM IN HAN DYNASTY
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作者 赵丰 《Journal of China Textile University(English Edition)》 EI CAS 1997年第4期60-65,共6页
The axle-treadle mechanism of Han loom consists of a set of components, including two pedals controlling one shaft via a central axle. Based on the new archaeological finds, especially the pottery loom model, the coll... The axle-treadle mechanism of Han loom consists of a set of components, including two pedals controlling one shaft via a central axle. Based on the new archaeological finds, especially the pottery loom model, the collection of Krishna Riboud, and the historical document, a kind of axle treadle loom with oblique warp frame was reconstructed by author. It might be applied in the central China at that time, especially in Shandong and Jiangsu areas, and it was not later than the Warring State period for the oblique axle treadle loom to come into being and reach a peak in the Han Dynasty. After that time, it was used with the vertical frame but lost the importance gradually. 展开更多
关键词 HISTORY of TEXTILE loom treadle
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Review and Prospect of the Shuttleless Loom Development
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作者 陈明 陈革 《Journal of China Textile University(English Edition)》 EI CAS 1999年第1期56-58,共3页
In this paper, a review of the shuttleless looms’ development shows that three types of shuttleless looms: rapier, Jet and gripper projectile, are now equally matchable with each other. A prospect of the shuttleless ... In this paper, a review of the shuttleless looms’ development shows that three types of shuttleless looms: rapier, Jet and gripper projectile, are now equally matchable with each other. A prospect of the shuttleless loom’s development is also dealt with. It can be predicted that both rapier and Jet looms will be developed further and the future development of a new type of modern weaving looms will be prosperous in the coming 21st century. 展开更多
关键词 thuttleleu loom RAPIER JET GRIPPER PROJECTILE .
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THE POTENTIALITY OF ENERGY-SAVING IN SHUTTLE LOOMS
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作者 叶晓峰 胡企贤 《Journal of Donghua University(English Edition)》 EI CAS 1989年第Z1期62-71,共10页
In this paper,the effects of loom speed fluctuation on the mean speed and on the power ofdriving motor were investigated and the expressions for these effects were derived.Based on theenergy relationships,a new index ... In this paper,the effects of loom speed fluctuation on the mean speed and on the power ofdriving motor were investigated and the expressions for these effects were derived.Based on theenergy relationships,a new index of equivalent fluctuation was introduced,the connection be-tween this equivalent fluctuation and the energy of speed function on frequency domain was thenfound.In addition to the above theme,the residual kinetic energy of the shuttle and pickingmechanism,taken as a considerable part in the potentiality of loom energy-saving was also ana-lysed.According to the results of theoretical analyses,the ways of energy-saving in looms weresuggested.Finally,taking the loom of 1511 type as a practical example,the potentiality ofenergy-saving was calculated. 展开更多
关键词 loom frequency DOMAINS SHUTTLE PICKING motion ENERGY-SAVING fluctuation
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KINETO-ELASTODYNAMICS OF A FLEXIBLE RAPIER LOOM
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作者 王生泽 陈明 夏金国 《Journal of China Textile University(English Edition)》 EI CAS 1994年第2期41-46,共6页
For a complicated high speed reciprocating machine to meet the requirements of precise motion of its mechanisms, a study of its kineto-elastodynamies is necessary. Here is an example to find out the cause of the misen... For a complicated high speed reciprocating machine to meet the requirements of precise motion of its mechanisms, a study of its kineto-elastodynamies is necessary. Here is an example to find out the cause of the misengagement of flexible rapiers, by means of kineto-elastodynamic analysis, so as to meet the requirements of flexible rapier loom′s design, with beat-up and weft insertion mechanisms operating at high speed. 展开更多
关键词 KINETO-ELASTODYNAMICS FLEXIBLE RAPIER loom WEFT insertion.
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Dynamics of Water Jet in Water Jet Looms
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作者 Li Kerang(李克让) +1 位作者 Chen Ming(陈明) 《Journal of Donghua University(English Edition)》 EI CAS 2001年第3期33-37,共5页
On the base of the study on dynamics of water jet in water jet looms, the parameters of water jet mechanism which affect the speed of water jet are analyzed and optimized. So the stability of the water jet can be impr... On the base of the study on dynamics of water jet in water jet looms, the parameters of water jet mechanism which affect the speed of water jet are analyzed and optimized. So the stability of the water jet can be improved to raise the speed of water jet as well as weft insertion rate and to enlarge the width of woven fabrics a lot. At the same time it also points out that to increase water jet speed and to prolong its affective jet time depend mainly on the accretion of spring rate (constant)of stiffness and the diminution of plunger's cross sectional area respectively. 展开更多
关键词 WATER JET WEFT insertion dynamics WATER JET looms
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A THEORETICAL ANALYSIS OF WORKING CHARACTER OF WEFT TENSION COMPENSATOR IN NEEDLE LOOMS
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作者 江志安 《Journal of China Textile University(English Edition)》 EI CAS 1995年第1期36-42,共7页
Based on the analysis, according to the principle of vibration, of the working character of weft tension compensator in needle looms, the paper studied the principle of tension compensation and introduced the idea of ... Based on the analysis, according to the principle of vibration, of the working character of weft tension compensator in needle looms, the paper studied the principle of tension compensation and introduced the idea of compensating coefficient. The paper also discussed some factors affecting the effect of tension compensation. 展开更多
关键词 NEEDLE looms WEFT tension tension compensation tension COMPENSATOR working CHARACTER compensating coefficient.
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A STUDY ON THE DYNAMIC RESPONSE OF CAM BEAT-UP MOTIONS FOR RAPIER LOOMS
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作者 施雷飚 陈明 《Journal of China Textile University(English Edition)》 EI CAS 1996年第2期48-55,共8页
Based on the requirements of the two-phase rapier loom’s beat-up system characteristics, the dynamic responses of its beat-up system to three different types of cam input motion are studied in this paper. Also, their... Based on the requirements of the two-phase rapier loom’s beat-up system characteristics, the dynamic responses of its beat-up system to three different types of cam input motion are studied in this paper. Also, their corresponding analytical comparisons are made. At the end of the paper, the authors put forward a proposal of new type cam beat-up motion for future practice. 展开更多
关键词 BEAT up motion dynamic response RAPIER loom simple HARMONIC double HARMONIC cycloidal TRIPLE HARMONIC
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Design of Electronic Weft-Insertion System for Three-Dimensional Loom
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作者 钱永明 闫红霞 +1 位作者 王永兴 陈革 《Journal of Donghua University(English Edition)》 EI CAS 2015年第3期466-469,共4页
The motion laws for rapier weft insertion mechanism are analyzed. According to the special requirements on rapier loom's weft-insertion system for weaving three-dimensional( 3-D) fabric,a new rapier electronic wef... The motion laws for rapier weft insertion mechanism are analyzed. According to the special requirements on rapier loom's weft-insertion system for weaving three-dimensional( 3-D) fabric,a new rapier electronic weft-insertion system is presented. The design principle for 3-D loom's weft insertion system is introduced,including the design of the motion law of electronic weft-insertion system,the driving system's hardware configure,and its software's controlling principle. The weft insertion system is computer-controlled and servocylinder driven so as to control the rapier's movement to insert the weft into the multi-shed while 3-D weaving. This method greatly simplifies the weft-insertion system,achieves weft-insertion with variable travel,and improves the flexibility and reliability. The weft insertion system has been applied in a 3-D loom successfully. 展开更多
关键词 three-dimensional(3-D) loom servo-cylinder weftinsertion RAPIER
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A RESEARCH ON THE DISTRIBUTION OF SHUTTLES ON THE BOX LOOM
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作者 杨明煜 《苏州大学学报(工科版)》 CAS 1991年第S1期3-12,共10页
The figure of shuttle distribution one side of the loom has been used to show the convel-sion of shuttle in picking process.The characteristics of the figure have been analysed andused to introduce a simple method for... The figure of shuttle distribution one side of the loom has been used to show the convel-sion of shuttle in picking process.The characteristics of the figure have been analysed andused to introduce a simple method for shuttle starting distribution. 展开更多
关键词 multiple BOX loom STARTING DISTRIBUTION of SHUTTLE
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Study on the Back Rest System of Looms
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作者 陈革 毛立民 +1 位作者 周亚勤 袁立新 《Journal of Donghua University(English Edition)》 EI CAS 2004年第1期109-111,共3页
Periodic variations of warp tension during a weaving cycle result in corresponding change of back rest position, and the oscillation of back rest affects the fluctuation of warp yarn in return. A mechanical model of b... Periodic variations of warp tension during a weaving cycle result in corresponding change of back rest position, and the oscillation of back rest affects the fluctuation of warp yarn in return. A mechanical model of back rest system of looms is presented on basis of auto control theory, and the factors affecting the dynamic performance of the back rest are analyzed. In the model, warp yarn is regarded as a viscoelastic medium, and the adjustable parameters and the adjusting range of the back rest system are increased, so the loom's applicability for the fabric's variety is enhanced. Finally, the methods of designing and adjusting the back rest are discussed, and a trend of back rest system development is given. 展开更多
关键词 loom back rest dynamic performance
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Study of Water Jet Impulse in Water-Jet Looms
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作者 李克让 麻伟巍 陈明 《Journal of Donghua University(English Edition)》 EI CAS 2005年第3期62-65,共4页
The watar jet impulse is brought forward to study the traction force of the water jet to the flying weft in water-jet looms. The distribution of the water jet impulse in the shed is tested by a sensor, and the influen... The watar jet impulse is brought forward to study the traction force of the water jet to the flying weft in water-jet looms. The distribution of the water jet impulse in the shed is tested by a sensor, and the influence of water jet parameters on the water jet impulse is analyzed. 展开更多
关键词 Wate-jet looms water-jet impulse traction force
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Replication of Gold In-woven Fabric of Korean Goryeo Dynasty on Chinese Draw Loom with a Major Pattern Sheet(da hua lou ji大花楼机)
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作者 卢辰宣 《Journal of Donghua University(English Edition)》 EI CAS 2004年第2期23-26,共4页
A kind of gold in-woven fabric of Korean Goryeo Dynasty was successfully replicated on a Chinese draw loom with a major pattern sheet in The Yunjin Research Institute, Nanjing city.
关键词 Gold in-woven fabric Goryeo Dynasty Draw loom Major pattern sheet
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