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The Mathematical Simulation of Brush Drums in a Dual Saw Cylinder Chamber Gin for the Purpose of Increasing the Quantity of Captured Cotton Fiber from Saw 被引量:5
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作者 Azizov Shuhrat Mamatovich Karimov Abdusamat Peter Arras 《World Journal of Mechanics》 2013年第1期58-61,共4页
An analysis of the efficiency of the ginning of cotton fibers with two saw cylinders has been carried out. In comparison to a one-cylinder machine, the 2 cylinder approach can help to preserve the natural characterist... An analysis of the efficiency of the ginning of cotton fibers with two saw cylinders has been carried out. In comparison to a one-cylinder machine, the 2 cylinder approach can help to preserve the natural characteristics of cotton fiber and seeds. This technology allows economizing electricity and decreasing damage to fiber and also increases the productivity of the machine. 展开更多
关键词 Gin SAW Cotton BRUSH drum Fiber SAW CYLINDER
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DESIGN AND APPLICATION OF MODEL DZI LOG GRAPPLE DRIVEN BY AN ELECTRIC DRUM
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作者 Wang Jingxin Pan DeluNortheast Forestry University 《Journal of Northeast Forestry University》 SCIE CAS CSCD 1993年第1期36-40,共5页
This article introduces the history and development of log grapple in China.Ac-cording to the special conditions of Chinese forest areas,we have selected log grapple driven byelectric drum,and have analyzed and calcul... This article introduces the history and development of log grapple in China.Ac-cording to the special conditions of Chinese forest areas,we have selected log grapple driven byelectric drum,and have analyzed and calculated its parameters theoretically.This is the first loggrapple driven by an electric drum made successfully in China.The Model DZ1 log grapple has alarge closing force,works safely and is suitable for the special forest working conditions inChina. 展开更多
关键词 LOG grapple ELECTRIC drum DESIGN and application FOREST operation
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LEAD ISOTOPE STUDIES ON ANCIENT BRONZE DRUMS OF GUANGXI CHINA
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作者 彭子成 万辅彬 +3 位作者 鲁冀邕 姚舜安 李世红 蒋廷瑜 《Nuclear Science and Techniques》 SCIE CAS CSCD 1991年第3期135-146,共12页
A study has been reported on <sup>208</sup>Pb/<sup>206</sup>Pb and <sup>207</sup>Pb/<sup>206</sup>Pb ratio variations in ancient drums and Cu-., Pb- ores from Guangxi, C... A study has been reported on <sup>208</sup>Pb/<sup>206</sup>Pb and <sup>207</sup>Pb/<sup>206</sup>Pb ratio variations in ancient drums and Cu-., Pb- ores from Guangxi, China and can indicate that the Cu- and Pb- bearing ores for making the Beiliu and the Lingshan type drums were taken from Tongshiling of Beiliu County and its vicinity, that were not only ancient sites for smelting the copper ores, but possibly also for casting the bronze drums. Some of the Lengshuichong type drums have abnormal Pb isotopic ratios, which means that they were made of special ore sources, one of the possibilities is that the ore material or the drums were transported from South- East Asia to Guangxi Province, because they have been excavated there too. 展开更多
关键词 ANCIENT drums Lead ISOTOPIC ratios ORE SOURCES
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SOME MECHANISMS OF DRUM BRAKE OSCILLATION AND SQUEAL
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作者 蒋伟康 《Journal of Shanghai Jiaotong university(Science)》 EI 1998年第2期20-26,共7页
ND SQUEALTX@蒋伟康IntroductionBecauseofitshighreliability,greatbrakingpowerandlowprice,adrumbrakeisoftenusedintr... ND SQUEALTX@蒋伟康IntroductionBecauseofitshighreliability,greatbrakingpowerandlowprice,adrumbrakeisoftenusedintrucksandbuses.However... 展开更多
关键词 vehicle noise VIBRATION drum BRAKE SQUEAL
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A Simple Approach to Determine Noise Frequency of Boiler Drum Level
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作者 余南华 苏明 《Journal of Shanghai Jiaotong university(Science)》 EI 2006年第1期66-70,共5页
This paper proposed a simple approach to determine noise frequency of boiler drum level in order to improve control performance. Based on analysis of uncertainty of drum level, the redundant oscillation component of s... This paper proposed a simple approach to determine noise frequency of boiler drum level in order to improve control performance. Based on analysis of uncertainty of drum level, the redundant oscillation component of signal, noise is ascribed to the surface wave of drum water. According to the characteristic of surface wave, a new method was proposed to determine noise’s frequency band. By gradually removing the lowest frequency component of signal, the variance of remained component is calculated and observed. An apparent turning point was found and the corresponding critical frequcncy was determined. With this result a low-pass filter was designed to separate noise component. Finally validation is conducted by comparing the proposed method and conventional ones. Results show the accuracy and simpleness of the proposed method. 展开更多
关键词 BOILER drum level noise cutoff frequency low-pass filter
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Effects of cooling rate on vermicular graphite percentage in a brake drum produced by onestep cored wire injection
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作者 Yu-shuang Feng Ze-sheng Ji +1 位作者 He-sheng Wu Yong-cheng Feng 《China Foundry》 SCIE CAS 2015年第5期349-353,共5页
In this research, a vermicular graphite cast iron brake drum was produced by cored wire injection in a one-step method. Silica sand and low-density alumina-silicate ceramic were used as molding materials in order to i... In this research, a vermicular graphite cast iron brake drum was produced by cored wire injection in a one-step method. Silica sand and low-density alumina-silicate ceramic were used as molding materials in order to investigate the effect of cooling rate on percentage of vermicular graphite and mechanical properties of the brake drum casting. Several thermocouples were inserted into the casting in the desired positions to measure the temperature change. By means of one-step cored wire injection, the two residual concentrations of Mg and RE were effectively controlled in the ranges of 0.013%-0.017% and 0.019%-0.025%, respectively, which are crucial for the production of vermicular graphite cast iron and the formation of vermicular graphite. In addition, the cooling rate had a significant effect on the vermicular graphite percentage. In the case of the silica mold brake drum casting, there was an obvious difference in the cooling rate with the wall change, leading to a change in vermicular graphite percentage from 70.8% to 90%. In the low-density alumina-silicate ceramic mold casting, no obvious change in temperature was detected by the thermocouples and the percentage of the vermicular graphite was stable at 85%. Therefore, the vermicular graphite cast iron brake drum with a better combination of mechanical properties could be obtained. 展开更多
关键词 cored wire injection in one-step vermicular graphite cast iron cooling rate vermicular graphite percentage brake drum
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Investigation of solids segregation of binary mixtures in a rotating drum at various Froude numbers
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作者 何玉荣 门玉宾 +1 位作者 刘元春 刘文铁 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2010年第5期701-705,共5页
To investigate the effect of the Froude number(Fr)on solid segregation in a rotating drum,a two dimensional mathematical modelling on solids behaviour in horizontally oriented rotating drums operated in rolling,cascad... To investigate the effect of the Froude number(Fr)on solid segregation in a rotating drum,a two dimensional mathematical modelling on solids behaviour in horizontally oriented rotating drums operated in rolling,cascading and cataracting modes has been carried out by using Euler-Euler multi-fluid model in Fluent6.2 environment.Small particles and big particles are used in the work as binary mixtures to investigate segregation characteristics.The effect of Froude number(rotating velocity)on the flow field is investigated.It is found that the model captures the main features of solids motion and segregation in the drum and numerical results agree well with limited experimental data for solid velocity. 展开更多
关键词 Solids segregation binary mixture rotating drum Froude number numerical simulation
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Particle breakage of sand subjected to friction and collision in drum tests
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作者 Fangwei Yu Chonglei Zhang +3 位作者 Qijun Xie Lijun Su Tao Zhao M.Qasim Jan 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2021年第2期390-400,共11页
This paper presents a laboratory experimental study on particle breakage of sand subjected to friction and collision,by a number of drum tests on granular materials(silica sand No.3 and ceramic balls)to investigate th... This paper presents a laboratory experimental study on particle breakage of sand subjected to friction and collision,by a number of drum tests on granular materials(silica sand No.3 and ceramic balls)to investigate the characteristics of particle breakage and its effect on the characteristics of grain size distribution of sand.Particle breakage increased in up convexity with increasing duration of drum tests,but increased linearly with increasing number of balls.Particle breakage showed an increase,followed by a decrease while increasing the amount of sand.There may be existence of a characteristic amount of sand causing a maximum particle breakage.Friction tests caused much less particle breakage than collision tests did.Friction and collision resulted in different mechanisms of particle breakage,mainly by abrasion for friction and by splitting for collision.The fines content increased with increasing relative breakage.Particle breakage in the friction tests(abrasion)resulted in a sharper increase but with a smaller total amount of fines content in comparison with that in the collision tests(splitting).For the collision tests,the fines content showed a decrease followed by an increase as the amount of sand increased,whereas it increased in up convexity with increasing number of balls.The characteristic grain sizes D_(10) and D_(30) decreased in down convexity with increasing relative breakage,which could be described by a natural exponential function.However,the characteristic grain sizes D50 and D60 decreased linearly while increasing the relative breakage.In addition,the coefficients of uniformity and curvature of sand showed an increase followed by a decrease while increasing the relative breakage. 展开更多
关键词 Grain size distribution drum tests Granular flow Particle breakage
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Thermomechanical Behavior of Brake Drums Under Extreme Braking Conditions
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作者 T.Khatir M.Bouchetara +3 位作者 K.Derrar M.Djafri S.Khatir M.Abdel Wahab 《Computers, Materials & Continua》 SCIE EI 2022年第8期2259-2273,共15页
Braking efficiency is characterized by reduced braking time and distance,and therefore passenger safety depends on the design of the braking system.During the braking of a vehicle,the braking system must dissipate the... Braking efficiency is characterized by reduced braking time and distance,and therefore passenger safety depends on the design of the braking system.During the braking of a vehicle,the braking system must dissipate the kinetic energy by transforming it into heat energy.A too high temperature can lead to an almost total loss of braking efficiency.An excessive rise in brake temperature can also cause surface cracks extending to the outside edge of the drum friction surface.Heat transfer and temperature gradient,not to forget the vehicle’s travel environment(high speed,heavy load,and steeply sloping road conditions),must thus be the essential criteria for any brake system design.The aim of the present investigation is to analyze the thermal behavior of different brake drum designs during the single emergency braking of a heavy-duty vehicle on a steeply sloping road.The calculation of the temperature field is performed in transient mode using a three-dimensional finite element model assuming a constant coefficient of friction.In this study,the influence of geometrical brake drum configurations on the thermal behavior of brake drums with two different materials in grey cast iron FG200 and aluminum alloy 356.0 reinforced with silicon carbide(SiC)particles is analyzed under extreme vehicle braking conditions.The numerical simulation results obtained using FE software ANSYS are qualitatively compared with the results already published in the literature. 展开更多
关键词 drum brake finite element method braking energy distribution friction heat power friction heat flux transient temperature field
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Reduction of Environmental Impact of Drum Machine Washing
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作者 Pieter Broer van der Weg (Peter) 《Journal of Applied Mathematics and Physics》 2020年第1期132-157,共26页
An improvement of efficiency of the horizontally rotating drum washing machine is possible by using a more open type of drum, essentially without suds in the annulus, by using a pump to wet the clothes during rotation... An improvement of efficiency of the horizontally rotating drum washing machine is possible by using a more open type of drum, essentially without suds in the annulus, by using a pump to wet the clothes during rotation and fall. Modelling and simulation are used to quantify these claims and further optimize the design of the horizontal washing machine. The flow of suds inside the deforming clothes at impact with the drum is calculated. The wash performance is shown to be largely proportional to the open perforation area in the drum. The traditional design uses 1/8 of drum area for the perforation holes. A significant reduction of water, detergent, electrical energy, and wash time, with parity in wash performance, provides a step towards a cleaner and more sustainable future. 展开更多
关键词 drum WASH MACHINE Design Efficiency Poroelastics DARCY Simulation MODELLING
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Feed-Drum和SkinAct膜鸣扩增型乐器的音准调控
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作者 米开朗基罗.路朋 洛伦佐.赛诺 刘志晟 《演艺科技》 2016年第2期40-44,共5页
介绍了Feed-Drum和SkinAct膜鸣扩增型乐器的研发背景,并对其鼓膜振荡模式图和控制系统中的音准调控方式做出理论分析。
关键词 膜鸣扩增型乐器 音乐装置 Feed-drum SkinAct 电子调制 音准控制
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Influence of the Mode of Discrete Drum Speed and the Number of Inputs on the Technological Parameters of the Yarn Produced
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作者 Yuldashev Jamshid 《Engineering(科研)》 CAS 2022年第12期536-543,共8页
This article is devoted to the research work aimed at improving the quality of yarns obtained by pneumomechanical spinning. The yarn quality indicators obtained at different speed modes of the pneumomechanical spinnin... This article is devoted to the research work aimed at improving the quality of yarns obtained by pneumomechanical spinning. The yarn quality indicators obtained at different speed modes of the pneumomechanical spinning machine discrete drum were studied and analyzed. The effect of the number of incisions of the sawtooth coatings on the discrete drum on the quality indicators of the yarn produced was also studied. The results of the experiments were analyzed by graphical and histogram methods, and alternative options were suggested. 展开更多
关键词 Fiber YARN Discrete drum Quality Text TOUGHNESS SPEED
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The Effects of a Drums Alive Kids® Beats Intervention vis a vis Behavior on Children with Developmental Delays
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作者 Carrie Ekins Peter R. Wright +3 位作者 Marianne Liebich Jacqueline Wright Henry Schulz Dean Owens 《Open Journal of Pediatrics》 2022年第1期67-74,共8页
The purpose of this study was to determine if the Drums Alive Kids Beats intervention could improve behavior in children with developmental delays (DD). The original pilot study that this study on behavior is linked t... The purpose of this study was to determine if the Drums Alive Kids Beats intervention could improve behavior in children with developmental delays (DD). The original pilot study that this study on behavior is linked to is titled, “The Effects of a Drums Alive<sup> </sup>Kids Beats Intervention on the Physical Performance and Motor Skills of Children with Developmental Delays,” which was published in the December edition of the Open Journal of Pediatrics (OJPED, Vol.11 No.4 2021). During the facilitation of said intervention on physical and motor skills, the facilitators noticed unanticipated improvements in behavior, both individually and as a community through better awareness, self-control, self-efficacy, social interaction, and positive energy. Therefore, while maintaining the integrity of the MOT 4 - 6 testing protocols and Drums Alive intervention, a parallel study was conducted to objectively measure six behavioral domains, namely, motivation, impulse control, coordination, concentration, implementation of tasks, and creativity using a self-designed measurement tool with three elements for each domain that was approved by Dr. Heiner Lagenkamp, Department of Sports and Physical Activities, Teaching and Research, Ruhr University, Germany. The 20 participants were German students between 5.10 and 10.2 years of age with no inclusion or exclusion characteristics who were divided into two intervention groups, IG Kindergarten (IG Kinder) and IG Elementary (IG Elem), with varied DD, i.e., transgressive behavior, ADHD, ADD, autism, anger management, visual acuity, self-control, and self-esteem. During the MOT 4 - 6 study and Drums Alive Kids Beats intervention, the facilitators monitored and assessed each participant for pre- and post-performance vis a vis behavior concurrently with physical and motoric skills. As the original study provided statistically significant improvements of between 14% - 24% in physical and motor skill performance with regards to overall scoring and 7 subdivisions of tasks, the results of this parallel study on behavior, with its 6 domains and 18 elements of between 24% - 28%, were even more compelling. The evidence indicated that the Drums Alive Kids Beats intervention with its multidisciplinary approach of music, movement, and drumming, could be used as an effective tool and therapeutic approach to improve behavior in children with developmental delays. 展开更多
关键词 BEHAVIOR MULTIDISCIPLINARY Music Movement drumming Motivation Impulse Control Coordination Concentration Implementation of Tasks Creativity Plasticity
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The Effects of a Drums Alive<sup>®</sup>Kids Beats Intervention on the Physical Performance and Motor Skills of Children with Developmental Delays
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作者 Carrie Ekins Peter R. Wright +3 位作者 Marianne Liebich Jacqueline Wright Henry Schulz Dean Owens 《Open Journal of Pediatrics》 2021年第4期832-839,共8页
The objective of this original pilot study was to determine if the Drums Alive<span style="white-space:nowrap;"><sup>&reg;</sup></span> Kids Beats intervention could provide stati... The objective of this original pilot study was to determine if the Drums Alive<span style="white-space:nowrap;"><sup>&reg;</sup></span> Kids Beats intervention could provide statistically significant improvements to physical and motor skill performance on participants with Developmental Delays (DD) using the Dusseldorf Motor-Proficiency-Test for children (MOT 4-6) model. The researchers selected the research-based Drums Alive Kids Beat intervention because of its multidisciplinary methodology that in previous studies demonstrated positive effects on physiological, psychological, neurological, educational, rhythmical, and socio-emotional literacy. Facilitators used standardized Drums Alive approved lesson plans and equipment to conduct the intervention through a battery of music, movement and drumming-centered exercises and activities. The 30 participants were German students between 4.9 and 10.2 years of age, without any inclusion or exclusion characteristics, who were divided into three groups consisting of two intervention groups: IG Kindergarten (IG Kinder), IG Elementary<span style="font-family:;" "=""><span style="font-family:Verdana;"> (IG Elem) with varied physical, social, and emotional DD that affected gross and fine motor skills, movement, coordination, and behavioral control;and, a Control Group (CG) that had normal physical and motor skill development (</span><b><span style="font-family:Verdana;">Table 1</span></b><span style="font-family:Verdana;">). The results of the study suggested that the Drums Alive Kids Beats intervention provided statistically significant improvements in physical and motor skill performance in children with DD, namely, 24% improvement (IG Kinder), 14% (IG Elem) vice a minor 4% improvement (CG). Of note, during this study to measure physical capability pre- and post-intervention, the facilitators noticed significant improvements in behavior in both IG groups;therefore, they chose to conduct a collateral study to measure six behavioral domains which will be documented in a future publication to demonstrate the exclusive relationship between the Drums Alive Kids Beats intervention and improvement in behavior.</span></span> 展开更多
关键词 MULTIDISCIPLINARY Music Movement drumming Developmental Delay Behavior
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Bronze Drum in Miao Customs
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《China & The World Cultural Exchange》 1998年第2期41-44,共4页
关键词 Bronze drum in Miao Customs
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Ancient Bronze Drums Play Happy Songs
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《China & The World Cultural Exchange》 1996年第2期40-42,共3页
关键词 Ancient Bronze drums Play Happy Songs
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The Drum Dance of the Yi People
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《China & The World Cultural Exchange》 1997年第1期60-60,共1页
关键词 The drum Dance of the Yi People
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The Drum and Gong FolkPerformance of Shanxi
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《China & The World Cultural Exchange》 1995年第5期46-47,共2页
关键词 The drum and Gong FolkPerformance of Shanxi
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Reliability Sensitivity Analysis for Drum Brake on Modal Stress
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作者 HE Ning ZHANG Delong ZHANG Qinghua 《International Journal of Plant Engineering and Management》 2021年第4期193-214,共22页
A reliability sensitivity analysis based on modal stress is presented and applied to predict the influence factors of parameters on drum brake.Firstly,the first 10 modes of prestress of the brake drum are performed in... A reliability sensitivity analysis based on modal stress is presented and applied to predict the influence factors of parameters on drum brake.Firstly,the first 10 modes of prestress of the brake drum are performed in the software ANSYS Workbench.According to the results of brake noise research,it can be detected whether the drum brake meets the results that the noise frequency range of 500-1000 Hz.The reliability sensitivity design of mechanical parts based on the normal distribution parameters for complex mechanical system is discussed.Secondly,according to the first order second moment(FOSM)theory on reliability,the reliability sensitivity of drum brake is analyzed and calculated,and compared with the Monte Carlo(MC)numerical simulation results,The variation rules of reliability sensitivity is given,which provides a theoretical basis for the design of drum brake. 展开更多
关键词 modal stress drum brake reliability sensitivity first order second moment
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Drum Dance in Suburban Xigaze
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作者 DOJE 《China's Tibet》 1995年第6期38-39,共2页
DrumDanceinSuburbanXigazeDOJEThebeautifulvillageknownasSemaislocatedapproximately10KmsouthofXigaze,anditiskn... DrumDanceinSuburbanXigazeDOJEThebeautifulvillageknownasSemaislocatedapproximately10KmsouthofXigaze,anditisknownassemachoi.InT... 展开更多
关键词 drum Dance in Suburban Xigaze
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