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双轴同转凸轮螺旋式低温榨油机的设计原理 被引量:1
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作者 岳巍 《农机化研究》 北大核心 2016年第8期117-119 140,共4页
根据螺杆式榨油机存在的问题,设计了一种双轴同转凸轮螺旋式榨油机。利用双凸轮形成的油料压榨腔,使油料作物在腔体内完成挤压、松弛、碾磨、破碎和混合。经过多腔压榨,多次重复,使得油料作物获得充分压榨,降低了油饼中的残油率。整个... 根据螺杆式榨油机存在的问题,设计了一种双轴同转凸轮螺旋式榨油机。利用双凸轮形成的油料压榨腔,使油料作物在腔体内完成挤压、松弛、碾磨、破碎和混合。经过多腔压榨,多次重复,使得油料作物获得充分压榨,降低了油饼中的残油率。整个压榨过程压力小、温度低,符合目前低温冷榨制油技术理念,生产出的油脂品质好,油饼蛋白质含量高。该榨油机的主要零部件可单独加工制造,组合安装,使得整个加工工艺简单,加工成本低。 展开更多
关键词 双轴同转榨油机 凸轮压榨腔 低温
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“双师共育,双轴同转”中职教学模式的构建与实施——以汽车运用与维修专业为例 被引量:1
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作者 陈军 唐德贵 温明勇 《教育科学论坛》 2017年第27期42-45,共4页
基于现代学徒制试点,探索"双师共育,双轴同转"的教学模式改革。通过引企入校搭建现代学徒制人才培养平台,按照专业教师和企业师傅1:1的比例配置,形成"共育"的形式,构建"教师+师傅"的专业课堂;以学校课堂... 基于现代学徒制试点,探索"双师共育,双轴同转"的教学模式改革。通过引企入校搭建现代学徒制人才培养平台,按照专业教师和企业师傅1:1的比例配置,形成"共育"的形式,构建"教师+师傅"的专业课堂;以学校课堂和企业现场为轴线,实现"双轴同转",培养学生的实践能力。 展开更多
关键词 现代学徒制 教学模式 双师共育 双轴同转 共同发展
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全回转汽车式挖掘机总体设计
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作者 王进 丘铭军 《筑路机械与施工机械化》 北大核心 2005年第10期45-48,共4页
介绍了利用汽车底盘如何确定全回转挖掘机的总体方案和主要参数,以及汽车底盘的选型和改造,并且提出了一种动力传递方案和液压系统,从而可以简化挖掘机的结构。
关键词 同转汽车式挖掘机 汽车底盘 总体设计 同转机构
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同转/对转双转子系统的动力学特性 被引量:14
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作者 蒋云帆 廖明夫 +3 位作者 刘永泉 王德友 金路 鲁鹏 《航空动力学报》 EI CAS CSCD 北大核心 2013年第12期2771-2780,共10页
建立了双转子动力学模型,引入中介轴承刚度和高、低压转子陀螺力矩的影响,利用数值分析和实验验证,揭示了同转/对转双转子系统临界转速特性和不平衡响应存在的差异,以及转速比对同转/对转双转子临界转速特性和不平衡响应的影响.结果表明... 建立了双转子动力学模型,引入中介轴承刚度和高、低压转子陀螺力矩的影响,利用数值分析和实验验证,揭示了同转/对转双转子系统临界转速特性和不平衡响应存在的差异,以及转速比对同转/对转双转子临界转速特性和不平衡响应的影响.结果表明:陀螺力矩是影响带有中介支承的双转子系统转子刚度的主要原因,其刚度变化与内、外转子的转速比大小和相对旋转方向有关,进而导致同转/对转双转子系统临界转速特性和不平衡响应发生改变;相比同结构的同转双转子,在相同的不平衡量作用下,对转双转子的不平衡响应更为显著.对转双转子进行动平衡时,应更加严格的控制内、外转子的不平衡量. 展开更多
关键词 同转 陀螺力矩 动力学特性
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光电系统检测回转误差的实验研究 被引量:4
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作者 罗海燕 翟超 +1 位作者 金熠 邢晓正 《仪器仪表学报》 EI CAS CSCD 北大核心 2008年第10期2141-2145,共5页
回转误差运动的光电检测系统基于摄影测量学原理,利用CCD图像传感器跟踪目标标靶特征点的运动轨迹,直接获得同转轴的回转运动,避免了现有传统方法必须通过误差分离间接得到回转误差的过程。标靶特征点位置的提取直接影响整个系统的测量... 回转误差运动的光电检测系统基于摄影测量学原理,利用CCD图像传感器跟踪目标标靶特征点的运动轨迹,直接获得同转轴的回转运动,避免了现有传统方法必须通过误差分离间接得到回转误差的过程。标靶特征点位置的提取直接影响整个系统的测量精度,因此针对高精度和高稳定性的要求提出了选用十字丝作为合作标志。系统软件部分基于MATLAB 7.0开发,主要对标靶选取实验对比分析以及十字丝特征点不同的提取方案探讨,模拟实验证明:直线拟合交点法具有较高的定位精度和良好的稳定性,可达到3.28μm的精度。 展开更多
关键词 十字丝 图像处理 同转精度 CCD
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跨铁路枢纽区五桥同步转体施工技术 被引量:3
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作者 谭芝文 熊斌 +4 位作者 刘灿 干昌洪 王以杰 戴亦军 陈灯强 《建筑结构》 CSCD 北大核心 2022年第S02期2948-2952,共5页
重庆市快速路二横线工程物流园区至礼白立交段全长14.4km,其中跨渭井、蔡东联络线主线桥上跨渭井上下线、蔡东联络线3条既有运营铁路,主线桥全长234m,上部结构包含5座T构梁,总重21500t。为最大限度减小对桥下既有铁路枢纽区运营线路造... 重庆市快速路二横线工程物流园区至礼白立交段全长14.4km,其中跨渭井、蔡东联络线主线桥上跨渭井上下线、蔡东联络线3条既有运营铁路,主线桥全长234m,上部结构包含5座T构梁,总重21500t。为最大限度减小对桥下既有铁路枢纽区运营线路造成影响,经综合比选,采用五桥同步转体施工。五桥同转施工中,采用跨铁路枢纽区多联多跨转体桥施工组织与安全控制技术、施工监控技术、同联多T构转体桥合龙体态调整及施工误差控制技术、合龙顺序及临时锁定技术、紧邻既有铁路转体桥跨中无干扰快速合龙技术,完成了该跨铁路枢纽区五桥同步转体施工。结果表明,多T构同步转体施工过程稳定,桥梁结构、线形等满足规范和设计要求。 展开更多
关键词 跨线桥 同步 同联多T构 五桥同转 体施工
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电子进动和回转仪的模拟教学
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作者 何宇红 许家丛 《延边大学学报(自然科学版)》 CAS 2002年第2期145-148,共4页
针对程守洙、江之永主编的《普通物理学》第 2册 (第 3版 )教材 ,在研究磁介质的磁化时提到的电子进动是导致抗磁质产生抗磁性的内因 ,这一课题进行教学研究 ,提出了适合理工科普通物理教学的模拟性教学方法 ,达到了较好的教学效果 .
关键词 模拟教学 电子进动 抗磁质 磁距 普通物理教学 抗磁性 同转效应
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《说文》“转注”与“六书”再思考 被引量:1
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作者 潘杰 《励耘语言学刊》 CSSCI 2016年第1期248-256,共9页
“转注”为“六书”之一,理解“转注”要依据“六书”性质及《说文》对所列汉字的具体解说。文字的基本功能是记录语言,“六书”应该是汉字记录汉语不同方式的归纳。所以我们认为,“转注”也是对汉字记录汉语在总体构形特点及规律方面... “转注”为“六书”之一,理解“转注”要依据“六书”性质及《说文》对所列汉字的具体解说。文字的基本功能是记录语言,“六书”应该是汉字记录汉语不同方式的归纳。所以我们认为,“转注”也是对汉字记录汉语在总体构形特点及规律方面的揭示与说明,核心在说明汉字构形凡形体相同则构意相同。《说文》的字例分析通过“凡某之属皆从某”的部首体例与“某与某同意”的形体分析条例相结合的方式,对“转注”内容进行了系统阐释、揭示与展示。 展开更多
关键词 六书 同意 构意
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中介轴承导致的高低压转子随动旋转现象
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作者 任志远 韦周庆 《中国新技术新产品》 2017年第8期58-59,共2页
某航空发动机装配后,对通过上部减速器机匣对高压转子进行摇转检查时,多次发现低压转子存在跟随转动现象,通过放大高、低压转子之间摩擦副间隙的方法未排除故障,进一步复查发现故障发动机中介轴承外环过盈量偏大导致轴承装配游隙偏下限... 某航空发动机装配后,对通过上部减速器机匣对高压转子进行摇转检查时,多次发现低压转子存在跟随转动现象,通过放大高、低压转子之间摩擦副间隙的方法未排除故障,进一步复查发现故障发动机中介轴承外环过盈量偏大导致轴承装配游隙偏下限,分析认为轴承装配时存在较大的负游隙是同转现象出现的原因,该现象对发动机使用质量无明显影响,控制轴承装配游隙后可以排除。 展开更多
关键词 中介轴承 自由游隙 装配游隙 同转
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浅谈俄语外来词记忆技巧
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作者 李颖 《鸡西大学学报(综合版)》 2002年第4期83-83,共1页
掌握俄语外来词记忆技巧就能更好地理解俄语外来词,记住外来词就能更好地掌握俄语。
关键词 俄语 外来词 记忆技巧 语义 同转
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Research on telecommunication resale service supply chain coordination with revenue-sharing contract 被引量:5
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作者 郑惠莉 达庆利 曹爱红 《Journal of Southeast University(English Edition)》 EI CAS 2004年第1期113-116,共4页
The competition and cooperation between traditional telecom operators and resale operators in the supply chain are discussed, when the telecom industry developed telecommunication resale service. Supply chain contract... The competition and cooperation between traditional telecom operators and resale operators in the supply chain are discussed, when the telecom industry developed telecommunication resale service. Supply chain contract is an effective way to coordinate the supply chain. This paper analyzes the revenue-sharing contract between telecom operators and resale operators. The study shows that by setting up a rational revenue-sharing ratio and wholesale price, a revenue-sharing contract can coordinate this supply chain, and telecom operators and resale operators can achieve a 'win-win' solution. 展开更多
关键词 telecommunication resale service supply chain coordination revenue-sharing contract
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Numerical Simulations of Polymer Melt Conveying in Co-Rotating Twin Screw Extruder 被引量:7
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作者 彭炯 陈晋南 《Journal of Beijing Institute of Technology》 EI CAS 2002年第2期189-192,共4页
The 3 D non isothermal flow of non Newtonian viscous polymer melt in a co rotating twin screw extruder is modeled. The distributions of the velocity, temperature, pressure and the viscous dissipation in the fl... The 3 D non isothermal flow of non Newtonian viscous polymer melt in a co rotating twin screw extruder is modeled. The distributions of the velocity, temperature, pressure and the viscous dissipation in the flow domain are presented by using a fluid dynamics analysis package (Polyflow). The numerical results show that the temperatures are high in the intermeshing region and on the screw surface, the maximum pressure and the minimum pressure occur in the intermeshing region, and the flow rate is almost proportional to the screw speed. 展开更多
关键词 twin screw extruder non Newtonian fluid numerical simulation
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In situ study on columnar-equiaxed transition and anaxial columnar dendrite growth of Al-15%Cu alloy by synchrotron radiography 被引量:3
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作者 李发国 东青 +5 位作者 张佼 戴永兵 付亚楠 谢红兰 尹付成 孙宝德 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第7期2112-2116,共5页
Directional solidification of Al-15% (mass fraction) Cu alloy was investigated by in situ and real time radiography which was performed by Shanghai synchrotron radiation facility (SSRF). The imaging results reveal... Directional solidification of Al-15% (mass fraction) Cu alloy was investigated by in situ and real time radiography which was performed by Shanghai synchrotron radiation facility (SSRF). The imaging results reveal that columnar to equiaxed transition (CET) is provoked by external thermal disturbance. The detaching and floating of fragments of dendrite arms are the prelude of the transition when the solute boundary layer in front of the solid-liquid interface is thin. And the dendrite triangular tip is the fracture sensitive zone. When the conditions are suitable, new dendrites can sprout and grow up. This kind of dendrite has no obvious stem and is named anaxial columnar dendrites. 展开更多
关键词 Al-15%Cu alloy directional solidification columnar to equiaxed transition synchrotron X-ray radiography
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Screening on Synergist of Bacillus thuringiensis Wettable Powder
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作者 葛东华 张晓红 +3 位作者 南宫自艳 宋萍 王勤英 曹克强 《Agricultural Science & Technology》 CAS 2012年第9期1915-1918,共4页
[Objective] This study aimed to screen the best synergistic material for Bt wettable powder and evaluate their synergistic effect. [Method] The synergism of six different kinds of additives for Bacillus thuringiensis ... [Objective] This study aimed to screen the best synergistic material for Bt wettable powder and evaluate their synergistic effect. [Method] The synergism of six different kinds of additives for Bacillus thuringiensis wettable powder (Bt WP) on the 2^nd instar larvae of Plutella xylostella was tested by method of leaf dipping in labora- tory. [Result] The mixtures of Bt with 0.1% ZnCl2, 0.5% ZnCl2, 1.0% ZnCl2, 1.0% MgCI2, 0.5% boric acid, 1.0% boric acid, 0.5% citric acid or 1.0% citric acid all ex- hibited synergistic effect, in which the synergistic effect of mixture containing 0.5% boric acid was the highest, with 17.2 synergistic ratio; followed by the mixture containing 1.0% ZnCl2, with 15.6 synergistic ratio. Moreover, addition of 0.5% boric acid could shorten the median lethal time of Bt wettable powder by about 10 h. After the mixtures of Bt with 0.5% boracic acid or 1.0% ZnCl2 was stored for 15 d at room temperature, toxicities of the two mixtures did not change significantly. [Conclusion] Boracic acid as the synergist of Bt wettable powder could not only increase insecti- cidal effect of Bt, but also accelerate its insecticidal rate. So, boracic acid could improve the disadvantages of Bt wettable powder such as poor insecticidal effect and slow insecticidal speed in a certain degree. 展开更多
关键词 Bacillus thuringiensis Synergism Cotoxicity factor Plutella xylostella
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全国首家木质、非木质刨花板同机生产技术在湘研制开发成功
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作者 何泽龙 陈和平 《林业机械与木工设备》 2005年第6期26-26,共1页
关键词 木质刨花板 非木质刨花板 同机生产技术 同转式干燥设备 生产能力 经济效益
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OB glue paste technique for establishing nude mouse human gastric cancer orthotopic transplantation models 被引量:15
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作者 Jun Shi Pin-Kang Wei Shen Zhang Zhi-Feng Qin Jun Li Da-Zhi Sun Yan Xiao Zhi-Hong Yu Hui-Ming Lin Guo-Jing Zheng Xiao-Mei Su Ya-Lin Chen Yan-Fang Liu Ling Xu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第30期4800-4804,共5页
AIM: To establish nude mouse human gastric cancer orthotopic transplantation models using OB glue paste technique. METHODS: Using OB glue paste technique, orthtopic transplantation models were established by implant... AIM: To establish nude mouse human gastric cancer orthotopic transplantation models using OB glue paste technique. METHODS: Using OB glue paste technique, orthtopic transplantation models were established by implanting SGC-7901 and NKN-45 human gastric cancer cell strains into the gastric wall of nude mice. Biological features, growth of the implanted tumors, the success rate of transplantation and the rate of auto-metastasis of the two models were observed. RESULTS: The success rates of orthotopic transplanration of the two models were 94.20% and 96%. The rates of hepatic metastasis, pulmonary metastasis, peritoneal metastasis, lymphocytic metastasis and splenic metastasis were 42.13% and 94.20%, 48.43% and 57.97%, 30.83% and 36.96%, 67.30% and 84.06%, and 59.75% and 10.53%, respectively. The occurrence of ascites was 47.80% and 36.96%. CONCLUSION: OB glue paste technique is easy to follow. The biological behaviors of the nude mouse human gastric cancer orthotopic transplantation models established with this technique are similar to the natural processes of growth and metastasis of human gastric cancer, and, therefore, can be used as an ideal model for experimental research of proliferative metastasis of tumors. 展开更多
关键词 Gastric tumor Tumor transplantation Disease models ANIMAL Nude mice
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New atom movement mechanism for tracking path on disordering AuCuI(A_8^(Au)A_4^(Cu)) compound 被引量:3
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作者 谢佑卿 彭红建 +2 位作者 刘心笔 李小波 聂耀庄 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第10期3221-3256,共36页
Taking experimental path on disordering AuCuI(AAuCu8A4)composed of A Au8 and ACu4 stem alloy genes as an example, three discoveries and a method were presented. The ability of Au Cu I(AAu Cu8 A4)to keep structure ... Taking experimental path on disordering AuCuI(AAuCu8A4)composed of A Au8 and ACu4 stem alloy genes as an example, three discoveries and a method were presented. The ability of Au Cu I(AAu Cu8 A4)to keep structure stabilization against changing temperature is attributed to the fact that the AAu8 and ACu4 potential well depths greatly surpass their vibration energies, which leads to the subequilibrium of experimental path. A new atom movement mechanism of AuCuI(AAuACu84)to change structure for suiting variation in temperature is the resonance activating-synchro alternating of alloy genes, which leads to heterogeneous and successive subequilibrium transitions. There exists jumping order degree, which leads to the existence of jumping Tj-temperature and an unexpected so-called "retro-effect" about jumping temperature retrograde shift to lower temperatures upon the increasing heating rate. A set of subequilibrium holographic network path charts were obtained by the experimental mixed enthalpy path method. 展开更多
关键词 INTERMETALLICS alloy gene order/disorder transformation resonance activating-synchro alternating mechanism thermodynamic properties equilibrium and subequilibrium holographic network path charts
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Identification and Comparative Analysis of DGAT1 Genes among Cotton and Other Model Plants
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作者 郭宁 胡利宗 +4 位作者 解恒昌 袁明月 王秋霞 周琳 王红星 《Agricultural Science & Technology》 CAS 2016年第7期1546-1550,1626,共6页
Diacylglycerol acyltransferase (DGAT) is the key enzyme that catalyzes the triacylglycerol biosynthesis. The comparative analysis was performed on the DGAT1 genes of cotton and other model plants. Sequence analysis ... Diacylglycerol acyltransferase (DGAT) is the key enzyme that catalyzes the triacylglycerol biosynthesis. The comparative analysis was performed on the DGAT1 genes of cotton and other model plants. Sequence analysis showed that most of the DGAT1 genes,with high variation of intron length and high conservation of intron phrase,from the cotton and other model plants had 16 exons. Additionally, 7 conserved motifs were present in these DGAT1 proteins. The core motifs were overlapped with the functional domain of DGAT1 protein. Phylogenetic analysis demonstrated that gene tree was highly consistent to species tree,suggesting that the evolutionary history of species was revealed by gene tree. There was single copy of DGAT1 gene in cotton,but at least two duplicated DGAT1 genes were iden- tified in rice,maize,poplar and moss genomes. The selective pressure analysis showed that the PtDGATla/PtDGATlb was under positive selection,but other four pairs of homologous genes were under negative selection. 17 positively selected sites were identified at subgroup level (P〉0.05),suggesting these subgroups under relaxed functional constraint. The findings provide a basis for further studying func- tion and evolution of DGAT1 genes in cotton and other model plants. 展开更多
关键词 Diacylglycerol acyltransferase Conserved motif COTTON Homologous gene EVOLUTION
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Adaptive multicascade attribute reduction based on quantum-inspired mixed co-evolution
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作者 丁卫平 王建东 +1 位作者 施佺 管致锦 《Journal of Southeast University(English Edition)》 EI CAS 2012年第2期145-150,共6页
Due to the fact that conventional heuristic attribute reduction algorithms are poor in running efficiency and difficult in accomplishing the co-evolutionary reduction mechanism in the decision table, an adaptive multi... Due to the fact that conventional heuristic attribute reduction algorithms are poor in running efficiency and difficult in accomplishing the co-evolutionary reduction mechanism in the decision table, an adaptive multicascade attribute reduction algorithm based on quantum-inspired mixed co-evolution is proposed. First, a novel and efficient self- adaptive quantum rotation angle strategy is designed to direct the participating populations to mutual adaptive evolution and to accelerate convergence speed. Then, a multicascade model of cooperative and competitive mixed co-evolution is adopted to decompose the evolutionary attribute species into subpopulations according to their historical performance records, which can increase the diversity of subpopulations and select some elitist individuals so as to strengthen the sharing ability of their searching experience. So the global optimization reduction set can be obtained quickly. The experimental results show that, compared with the existing algorithms, the proposed algorithm can achieve a higher performance for attribute reduction, and it can be considered as a more competitive heuristic algorithm on the efficiency and accuracy of minimum attribute reduction. 展开更多
关键词 attribute reduction mixed co-evolution self- adaptive quantum rotation angle performance experience record elitist competition pool
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Design and FPGA verification of a novel reliable real-time data transfer system 被引量:2
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作者 Yu-ping LIAN Yan HAN +2 位作者 Ming-xu HUO Jin-long CHEN Yan ZHANG 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第10期1406-1410,共5页
Considering the increasing use of information technology with established standards, such as TCP/IP and XML in modem industrial automation, we present a high cost performance solution with FPGA (field programmable ga... Considering the increasing use of information technology with established standards, such as TCP/IP and XML in modem industrial automation, we present a high cost performance solution with FPGA (field programmable gate array) implementation of a novel reliable real-time data transfer system based on EPA (Ethemet for plant automation) protocol and IEEE 1588 standard. This combination can provide more predictable and real-time communication between automation equipments and precise synchronization between devices. The designed EPA system has been verified on Xilinx Spartan3 XC3S1500 and it consumed 75% of the total slices. The experimental results show that the novel industrial control system achieves high synchronization precision and provides a 1.59-ps standard deviation between the master device and the slave ones. Such a real-time data transfer system is an excellent candidate for automation equipments which require precise synchronization based on Ethemet at a comparatively low price. 展开更多
关键词 Ethemet for plant automation (EPA) IEEE 1588 Precise synchronization Real-time data transfer
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