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曲面胶印机步进分度系统建模及有限元分析 被引量:1
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作者 袁峰 王建昊 《包装工程》 CAS CSCD 北大核心 2016年第23期191-195,共5页
目的建立曲面胶印机步进分度系统的三维模型,对步进分度系统进行模态分析和谐响应分析。方法根据共轭曲面原理建立弧面分度凸轮机构的三维模型,利用Ansys Workbench对步进分度系统进行有限元分析。结果利用Pro/E建立了步进分度系统的三... 目的建立曲面胶印机步进分度系统的三维模型,对步进分度系统进行模态分析和谐响应分析。方法根据共轭曲面原理建立弧面分度凸轮机构的三维模型,利用Ansys Workbench对步进分度系统进行有限元分析。结果利用Pro/E建立了步进分度系统的三维模型,其中详细介绍了弧面分度凸轮机构的建模步骤。由模态分析得出步进分度系统的前六阶振型和固有频率,由谐响应分析得出步进分度系统在冲击载荷下的幅频响应曲线,为进一步进行步进分度系统的动态优化设计奠定了基础。结论曲面胶印机的步进分度系统工作可靠,具有良好的动力学特性,可有效保证印刷质量。 展开更多
关键词 曲面胶印机 步进分度系统 弧面分度凸轮机构 模态分析 谐响应分析
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提高数控分度系统定位精度的途径
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作者 陈耿 《中国机械工程》 CAS CSCD 北大核心 1996年第6期86-88,共3页
分析了现有数控分度系统采用蜗杆机构为主传动的局限性,认为应该用新型机构予以取代。在对行星钢球传动机构进行全面分析的基础上,以这种机构为主传动,进行了数控分度的尝试,取得了满意效果。
关键词 蜗杆机构 钢球传动机构 数控分度系统 定位精度
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热电阻自动分度系统
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作者 谌立新 张遇鸣 《仪器仪表标准化与计量》 1999年第2期21-24,共4页
本文针对热电阻的测试特点,选用GPIB总线作为测试采样总线,采用RS232C总线作为温度控制总线,组成自动测试系统,形成闭环控制,实现了铂热电阻电阻温度特性的自动测试。并在该自动测试系统上开展了铂热电阻电阻温度特性自动测试技术... 本文针对热电阻的测试特点,选用GPIB总线作为测试采样总线,采用RS232C总线作为温度控制总线,组成自动测试系统,形成闭环控制,实现了铂热电阻电阻温度特性的自动测试。并在该自动测试系统上开展了铂热电阻电阻温度特性自动测试技术方法的研究。 展开更多
关键词 热电阻 分离 自动测试 自动分度系统 总线
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高速冲槽机分度系统不准造成的原因分析
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作者 宣传金 吴学会 《防爆电机》 2002年第1期45-46,共2页
简述了造成高速冲槽机分度系统不准的原因及分析。
关键词 精度 高速冲槽机分度系统 轴承 专用机床
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磨齿机的多分度系统
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作者 丁铭懋 《磨床与磨削》 北大核心 1989年第4期58-60,共3页
磨齿机一般都设有工作分度,手动分度和连续分度功能,而多为单分度,即分一度,齿轮工件转过一齿,在砂轮与齿轮相对运动中磨削齿面,直至一个循环结束。单分度型式的磨齿机适用于磨削齿数较多的工件,为了扩大磨齿机使用范围,实现少齿数(如Z&... 磨齿机一般都设有工作分度,手动分度和连续分度功能,而多为单分度,即分一度,齿轮工件转过一齿,在砂轮与齿轮相对运动中磨削齿面,直至一个循环结束。单分度型式的磨齿机适用于磨削齿数较多的工件,为了扩大磨齿机使用范围,实现少齿数(如Z<10)磨削,便出现了双分度。 展开更多
关键词 磨齿机 分度系统 控制
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M8612A型花键轴磨床液压分度系统的改进
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作者 陈友侃 申华荣 《磨床与磨削》 北大核心 1993年第1期75-77,共3页
1960年以来,上海机床厂生产的 M8612型花键轴磨床的分度系统历经由液压传动改为电器传动最后又改为液压传动结构。尽管液压传动实用可靠,但由于传动动作复杂,液压分度系统虽经1984年作较大改进(详见《磨床与磨削》1984年第4期)
关键词 花键轴磨床 液压分度系统
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MG6450A滚刀刃磨床液压分度控制系统的改进 被引量:1
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作者 王飞 《设备管理与维修》 2002年第7期18-18,共1页
我公司MG6450A滚刀刃磨床担任着公司大直径、大模数滚刀的磨削,可磨滚刀最大直径500mm。刃磨时,磨头滑板的往复运动、滚刀的分度运动、刃磨螺旋槽滚刀的螺旋运动均由机械液压自动传动。机床投产后,滚刀的分度运动一直不正常,严重影响公... 我公司MG6450A滚刀刃磨床担任着公司大直径、大模数滚刀的磨削,可磨滚刀最大直径500mm。刃磨时,磨头滑板的往复运动、滚刀的分度运动、刃磨螺旋槽滚刀的螺旋运动均由机械液压自动传动。机床投产后,滚刀的分度运动一直不正常,严重影响公司的齿轮生产。 展开更多
关键词 滚刀刃磨床 液压分度控制系统 改进
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系统可分度与系统要素级别划分
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作者 李书波 李健隽 管伟诗 《哈尔滨建筑大学学报》 1996年第1期70-76,共7页
本文证明了系统、系统的顶要素集、系统的基要素集三者可分度相等,并给出了在系统的可达矩阵上直接标号划分系统要素级别的方法。据此可得出系统的可分度及系统的层次结构.比已有方法简便直观。
关键词 建筑物 质量管理 系统分度 系统要素
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M6420B型滚刀刃磨机床分度头数控改造设计 被引量:1
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作者 裴玲 胡风锌 《湖北工学院学报》 2004年第4期51-52,59,共3页
针对M6420B滚刀磨床分度头结构复杂、分度不准确、易损坏刀具等问题,应用数控技术对滚刀刃磨分度系统进行改造设计.改进后的效果显示,刃磨过程中的各种运动相互协调准确.
关键词 数控技术 液压系统 机械改造 分度系统 滚刀刃磨
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滚刀磨床的数控改造机电一体化设计 被引量:1
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作者 王英春 徐祖建 +1 位作者 程思 王英杰 《机床与液压》 北大核心 2002年第3期145-146,163,共3页
应用简易数控对M64 2 0B滚刀磨床所进行的机电一体化Mechatronics设计 ,将机械装置和数控技术有机结合起来 ,构成一个完整的分度系统。巧妙地解决了主轴刚性连接与柔性传动间的衔接 。
关键词 滚刀磨床 数控改造 机电一体化 设计 分度系统 步进电机
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M6450A滚刀磨床的改进
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作者 郑发农 《设备管理与维修》 2000年第9期37-37,共1页
一台M6450A滚刀磨床,主轴分度不稳定,总是在分度运动未完成时,工作台就反向,容易碰坏砂轮发生事故,一直不能正常使用。 主轴的分度运动是由液动机完成的。如果将液动机的工作压力调高,虽能够完成正常分度,但定位冲击过大;反之,如果将压... 一台M6450A滚刀磨床,主轴分度不稳定,总是在分度运动未完成时,工作台就反向,容易碰坏砂轮发生事故,一直不能正常使用。 主轴的分度运动是由液动机完成的。如果将液动机的工作压力调高,虽能够完成正常分度,但定位冲击过大;反之,如果将压力调低,虽无冲击,但不能保证正常分度。为两者兼顾。 展开更多
关键词 滚刀磨床 改进 分度系统 液压系统 安全装置
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新型光电铣槽机
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作者 马光 施兆良 任宝兴 《电动工具》 1999年第4期26-27,共2页
光电跟踪铣槽机因具有铣削精度高、质量好、自动化程序高等优点,已在电机制造行业中得到了广泛应用,成为电机制造行业的关键装备之一。我们研制光电铣槽机已有十年之久,经过多年实践和不断改进,在设计研制铣槽机方面积累了丰富的经验。... 光电跟踪铣槽机因具有铣削精度高、质量好、自动化程序高等优点,已在电机制造行业中得到了广泛应用,成为电机制造行业的关键装备之一。我们研制光电铣槽机已有十年之久,经过多年实践和不断改进,在设计研制铣槽机方面积累了丰富的经验。近年来,高新技术日新月异,计算机技术。 展开更多
关键词 电机制造 光电铣槽机 光电传感器 分度系统
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ACS-based resource assignment and task scheduling in grid
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作者 祁超 张璟 李军怀 《Journal of Southeast University(English Edition)》 EI CAS 2007年第3期451-454,共4页
To solve the deadlock problem of tasks that the interdependence between tasks fails to consider during the course of resource assignment and task scheduling based on the heuristics algorithm, an improved ant colony sy... To solve the deadlock problem of tasks that the interdependence between tasks fails to consider during the course of resource assignment and task scheduling based on the heuristics algorithm, an improved ant colony system (ACS) based algorithm is proposed. First, how to map the resource assignment and task scheduling (RATS) problem into the optimization selection problem of task resource assignment graph (TRAG) and to add the semaphore mechanism in the optimal TRAG to solve deadlocks are explained. Secondly, how to utilize the grid pheromone system model to realize the algorithm based on ACS is explicated. This refers to the construction of TRAG by the random selection of appropriate resources for each task by the user agent and the optimization of TRAG through the positive feedback and distributed parallel computing mechanism of the ACS. Simulation results show that the proposed algorithm is effective and efficient in solving the deadlock problem. 展开更多
关键词 GRID resource assignment task scheduling ant colony system (ACS) task resource assignment graph (TRAG) SEMAPHORE
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Possible emissions of N_2O from plants in coniferous-deciduous mixed forests
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作者 徐慧 张秀君 +3 位作者 黄斌 韩士杰 黄国宏 陈冠雄 《Journal of Forestry Research》 SCIE CAS CSCD 2001年第1期13-17,共7页
Aboveground vertical profiles of N2O concentrations were measured with in two natural coniferous-deciduous mixed forests of 1998 and 1999 in Changbai M ountain. Significant high N2O concentrations were found in six pr... Aboveground vertical profiles of N2O concentrations were measured with in two natural coniferous-deciduous mixed forests of 1998 and 1999 in Changbai M ountain. Significant high N2O concentrations were found in six profiles out of t welve profiles. The results showed that high concentrations were 3.03% to 64.9% higher than the "normal concentrations" in these six profiles. Differences betwe en the high concentrations and the "normal concentrations" were statistically si gnificant. The simultaneous occurrence of high concentrations at/nearby the cano py height and normal concentrations at the trunk space height indicated an efflu x of N2O from foliage to atmosphere. This study afforded evidence supporting tha t plant per se, besides forest soil, was an important source of atmospheric N2O in a forest ecosystem. 展开更多
关键词 Nitrous oxide Concentration profile Plant Forest ecosystem
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Analysis on the Origin and Phylogenetic Status of Tong Sheep Using 12 Blood Protein and Nonprotein Markers
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作者 孙伟 常洪 +5 位作者 杨章平 耿荣庆 角田健司 任战军 陈宏宇 Musa H.Hussein 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第12期1097-1105,共9页
This study is based on the Tong sheep obtained by the random sampling method of typical colonies in the central area of Baishui County in Shaanxi Province, China. An investigation was undertaken to clarify the gene co... This study is based on the Tong sheep obtained by the random sampling method of typical colonies in the central area of Baishui County in Shaanxi Province, China. An investigation was undertaken to clarify the gene constitution of blood protein and nonprotein types of Tong sheep. Twelve genetic markers were examined by starch-gel electrophoresis and cellulose acetate electrophoresis. Polymorphism in Tong sheep was found at the following 10 loci, transferrin (Tf), alkaline phosphatase (Alp), leucine aminopeptidase (Lap), arylesterase (Ary-Es), hemoglobin-β (Hb-β), X-protein (X-p), carbonic anhydrase (CA), catalase (Cat), malate dehydrogenase (MDH), and lysine (Ly), whereas, albumin (A1) and postalbumin (Po) loci were monomorphic. Genetic approach degree method and phylogenetic relationship clustering method were used to judge the origin and phylogenetic status of Tong sheep. Results from both methods maintained that Tong sheep belonged to the "Mongolia group", and Mongolia sheep was the origin of Tong sheep. This was also supported by the history of Tong sheep breeding. Compared to the phylogenetic relationship clustering method, the genetic approach degree method was more reliable for the extraction from East and South of Central Asia, and was more effective in reflecting the breeding course of Tong sheep. 展开更多
关键词 Tong sheep ORIGIN phylogenetic status genetic approach degree phylogenetic relationship clustering
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Y631K花键轴铣床加工范围的改进
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作者 杨宏梅 刘铁汉 《重庆重汽科技》 2001年第2期15-17,共3页
为使旧设备Y631K能够适应汽车新产品加工的需要,本文以被加工件的数据为依据,通过分析Y631K花键轴铣床的分度系统,进行传动比和齿轮的可靠性设计计算,使Y631K由原来只能加工4种规格的花键增加到20种以上。文中还就引起切削振动的原... 为使旧设备Y631K能够适应汽车新产品加工的需要,本文以被加工件的数据为依据,通过分析Y631K花键轴铣床的分度系统,进行传动比和齿轮的可靠性设计计算,使Y631K由原来只能加工4种规格的花键增加到20种以上。文中还就引起切削振动的原因进行分析,找出解决的措施,满足了生产的需要。 展开更多
关键词 Y631K花键轴铣床 加工范围 改进 汽车 分度系统 传动计算
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Mixed refrigerant composition shift due to throttle valves opening in auto cascade refrigeration system 被引量:5
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作者 许雄文 刘金平 曹乐 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第1期199-204,共6页
Auto cascade refrigeration(ACR) cycle with phase separators is widely used in the cryogenic system. The composition of mixed refrigerant has a great effect on the performance of the system. Based on the assumption of ... Auto cascade refrigeration(ACR) cycle with phase separators is widely used in the cryogenic system. The composition of mixed refrigerant has a great effect on the performance of the system. Based on the assumption of infinite volume of phase separator, ACR system with one phase separator is simulated in this paper. The variation of refrigerant composition under different valves opening is obtained. A related experimental system is set up to verify the variation. The result shows that when the valve opening connected to the evaporator increases or the valve opening under the phase separator decreases, the low-boiling component concentration of the working mixture passing through the compressor and condenser increases, while the high-boiling component concentration decreases. Furthermore, the variations of condensation pressure and evaporation pressure under different valves opening are also observed. This paper is helpful to deepen the understanding of ACR system. 展开更多
关键词 Auto cascade REFRIGERATION Composition shift THROTTLE
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A Molecular Phylogeny of Macaca Based on Mitochondrial Control Region Sequences 被引量:8
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作者 李青青 张亚平 《Zoological Research》 CAS CSCD 北大核心 2004年第5期385-390,共6页
Nucleotide sequences of segments of the mitochondrial control regions were analyzed to infer the phylogenetic relationships among 7 macaques.High nucleotide diversity in Macaca assamensis and relatively low diversity ... Nucleotide sequences of segments of the mitochondrial control regions were analyzed to infer the phylogenetic relationships among 7 macaques.High nucleotide diversity in Macaca assamensis and relatively low diversity in M.thibetana were found.Based on the ML tree from control regions,species in our study can roughly be sorted into three species groups except for the phylogenetic position of M.fascicularis,i.e.,silenus group,including M.leonina;sinica group,including M.arctoides,M.assamensis,and M.thibetana;and fascicularis group,including M.mulatta and M.cyclopis.A discrepancy between earlier studies (Fooden & Lanyon,1989;Tosi et al,2003a;Deinard & Smith,2001;Evans et al,1999;Hayasaka et al,1996;Morales & Melnick,1998),our result supported the hypothesis that M.fascicularis diverged earlier than M.leonina.Mitochondrial paraphyly in eastern M.mulatta (with respect to M.cyclopis) and eastern M.assamensis (with respect to M.thibetana) were clearly observed in our study.In accordance with the results of Y chromosome,allozyme,nuclear genes and some morphological data (Delson,1980;Fooden & Lanyon,1989;Fooden,1990;Tosi et al,2000,2003a,b;Deinard & Smith,2001),our study on control region sequences supported M.arctoides to be classified into the sinica group.However,this result disagreed with the previous mtDNA studies (Hayasaka et al,1996;Morales & Melnick,1998;Tosi et al,2003a). 展开更多
关键词 MACACA MACAQUE Mitochondrial DNA Control region PHYLOGENY
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Natural regeneration characteristics of Pinus sylvestris var. mongolica forests on sandy land in Honghuaerji, China 被引量:22
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作者 ZHU Jiao-jun KANG Hong-zhang +2 位作者 TAN Hui XU Mei-ling WANG Jun 《Journal of Forestry Research》 SCIE CAS CSCD 2005年第4期253-259,共7页
Natural regeneration in Mongolian pine, Pinus sylvesttis var. mongolica, forest at Honghuaerji of China (the original of the natural Mongolian pine, forest on sandy land) was studied in 2004. The total mean values o... Natural regeneration in Mongolian pine, Pinus sylvesttis var. mongolica, forest at Honghuaerji of China (the original of the natural Mongolian pine, forest on sandy land) was studied in 2004. The total mean values of regeneration indexes were higher in mature stands (more than 80% individual stems were older than 50 years), the maximum of regeneration index reached 29 seedlings, m^ 2, with lowest values in the younger stand, e.g., in 32-year old and 43-year old stands. The stand age was an important factor determining the natural regeneration, which was the best in the older stands in this investigation (e.g. about 80-year old). The regeneration index seemed not to be closely in relation to canopy openness although Mongolian pine is a photophilic tree species. In each type of gaps, natural regeneration was very well. Regeneration indexes were satisfactory at the south and east edges in the circle gaps; and at the east edge of the narrow-square gaps. Results indicated that Mongolian pine, seedlings could endure shading understory, but it would not enter the canopy layer without gap or large disturbance, e.g., fire, wind/snow damage or clear cutting etc. These results may provide potentially references to the management and afforestation of Mongolian pine, plantations on sandy land in arid and semi-arid areas. Researches such as the comprehensive comparisons on regeneration, structure and ecological conditions and so on between natural Mongolian pine, forests and plantations should be conducted in the future. 展开更多
关键词 Pinus sylvestris var. mongolica Mongolian pine Sandy land Natural regeneration Canopy openness Forest gap Regeneration index
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Integral Optimization of Systematic Parameters of Flip-Flow Screens 被引量:1
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作者 翟宏新 《Journal of China University of Mining and Technology》 2004年第1期77-81,共5页
The synthetic index K s for evaluating flip-flow screens is proposed and systematically optimized in view of the whole system. A series of optimized values of relevant parameters are found and then compared with those... The synthetic index K s for evaluating flip-flow screens is proposed and systematically optimized in view of the whole system. A series of optimized values of relevant parameters are found and then compared with those of the current industrial specifications. The results show that the optimized value K s approaches the one of those famous flip-flow screens in the world. Some new findings on geometric and kinematics parameters are useful for improving the flip-flow screens with a low K s value, which is helpful in developing clean coal technology. 展开更多
关键词 synthetic index Ks flip-flow screen clean coal optimization fines sieving
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