Aiming at the problems such as more repeatedly design and longer design cycle, in this paper, the similarity theory was introduced to the design process of the key structures of flotation machine. The impeller and U-s...Aiming at the problems such as more repeatedly design and longer design cycle, in this paper, the similarity theory was introduced to the design process of the key structures of flotation machine. The impeller and U-shaped tank of flotation machine system were analyzed as similarity unit. Meanwhile, the level of similarity of the units and the similarity of the system were calculated. Based on the analysis of the impeller and the size of U-shaped tank, the similarity criteria were derived. The derived conclusions are： （1） The relationship between the diameter of the impeller and the volume of the tank was power function and calculated as the similarity criteria of the impeller; （2） The relationship between the ratio between the U-shaped tank＇s cross-sectional area and impeller＇s diameter and the volume of the tank was power function and calculated as the similarity criterions of the U-shaped tank. Using the similarity criterion combined with computer technology and database technology to realize part and system serialization design. The results show that the research can efficiency. avoid repeatedly design, shorten design cycle, and raise the design展开更多
A new microreactor with continuous serially connected micromixers(CSCM)was tailored for the coprecipitation process to synthesize Fe_(3)O_(4) nanoparticles.Numerical simulation reveals that the two types of CSCM micro...A new microreactor with continuous serially connected micromixers(CSCM)was tailored for the coprecipitation process to synthesize Fe_(3)O_(4) nanoparticles.Numerical simulation reveals that the two types of CSCM microchannels(V-typed and U-typed)proposed in this work exhibited markedly better mixing performances than the Zigzag and capillary microchannels due to the promotion of Dean vortices.Complete mixing was achieved in the V-typed microchannel in 2.7 s at an inlet Reynolds number of 27.Fe_(3)O_(4) nanoparticles synthesized in a planar glass microreactor with the V-typed microchannel,possessing an average size of 9.3 nm and exhibiting superparamagnetism,had obviously better dispersity and uniformity and higher crystallinity than those obtained in the capillary microreactor.The new CSCM microreactor developed in this work can act as a potent device to intensify the synthesis of similar inorganic nanoparticles via multistep chemical precipitation processes.展开更多
This article presents two designs,the Transaction Serial Format(TSF)and the Transaction Array Model(TAM).Together,they provide full,efficient,transaction serialization facilities for devices with limited onboard energ...This article presents two designs,the Transaction Serial Format(TSF)and the Transaction Array Model(TAM).Together,they provide full,efficient,transaction serialization facilities for devices with limited onboard energy,such as those in an Internet of Things(IoT)network.TSF provides a compact,non-parsed,format that requires minimal processing for transaction deserialization.TAM provides an internal data structure that needs minimal dynamic storage and directly uses the elements of TSF.The simple lexical units of TSF do not require parsing.The lexical units contain enough information to allocate the internal TAM data structure efficiently.TSF generality is equivalent to XML and JSON.TSF represents any XML document or JSON object without loss of information,including whitespace.The XML equivalence provides a foundation for the performance comparisons.A performance comparison of a C reference implementation of TSF and TAM to the popular Expat XML library,also written in C,shows that TSF reduces deserialization processor time by more than 80%.展开更多
针对工业机器人在高度制造领域精度不高的问题,本文提出了一种基于POE模型的工业机器人运动学参数二次辨识方法。阐述了基于指数积(Product of exponential, POE)模型的运动学误差模型构建方法,并建立基于POE误差模型的适应度函数;为实...针对工业机器人在高度制造领域精度不高的问题,本文提出了一种基于POE模型的工业机器人运动学参数二次辨识方法。阐述了基于指数积(Product of exponential, POE)模型的运动学误差模型构建方法,并建立基于POE误差模型的适应度函数;为实现高精度的参数辨识,提出了一种二次辨识方法,先利用改进灰狼优化算法(Improved grey wolf optimizer, IGWO)实现运动学参数误差的粗辨识,初步将Staubli TX60型机器人的平均位置误差和平均姿态误差分别从(0.648 mm, 0.212°)降低为(0.457 mm, 0.166°);为进一步提高机器人的精度性能,再通过LM(Levenberg-Marquard)算法进行参数误差的精辨识,最终将Staubli TX60型机器人平均位置误差和平均姿态误差进一步降低为(0.237 mm, 0.063°),机器人平均位置误差和平均姿态误差分别降低63.4%和70.2%。为了验证上述二次辨识方法的稳定性,随机选取5组辨识数据集和验证数据集进行POE误差模型的参数误差辨识,结果表明提出的二次辨识方法能够稳定、精确地辨识工业机器人运动学参数误差。展开更多
基金Supported by National Natural Science Foundation of China (Grant No.51275145)
文摘Aiming at the problems such as more repeatedly design and longer design cycle, in this paper, the similarity theory was introduced to the design process of the key structures of flotation machine. The impeller and U-shaped tank of flotation machine system were analyzed as similarity unit. Meanwhile, the level of similarity of the units and the similarity of the system were calculated. Based on the analysis of the impeller and the size of U-shaped tank, the similarity criteria were derived. The derived conclusions are： （1） The relationship between the diameter of the impeller and the volume of the tank was power function and calculated as the similarity criteria of the impeller; （2） The relationship between the ratio between the U-shaped tank＇s cross-sectional area and impeller＇s diameter and the volume of the tank was power function and calculated as the similarity criterions of the U-shaped tank. Using the similarity criterion combined with computer technology and database technology to realize part and system serialization design. The results show that the research can efficiency. avoid repeatedly design, shorten design cycle, and raise the design
基金the financial support from the National Natural Science Foundation of China(21808059)the Fundamental Research Funds for the Central Universities(JKA01221712).
文摘A new microreactor with continuous serially connected micromixers(CSCM)was tailored for the coprecipitation process to synthesize Fe_(3)O_(4) nanoparticles.Numerical simulation reveals that the two types of CSCM microchannels(V-typed and U-typed)proposed in this work exhibited markedly better mixing performances than the Zigzag and capillary microchannels due to the promotion of Dean vortices.Complete mixing was achieved in the V-typed microchannel in 2.7 s at an inlet Reynolds number of 27.Fe_(3)O_(4) nanoparticles synthesized in a planar glass microreactor with the V-typed microchannel,possessing an average size of 9.3 nm and exhibiting superparamagnetism,had obviously better dispersity and uniformity and higher crystallinity than those obtained in the capillary microreactor.The new CSCM microreactor developed in this work can act as a potent device to intensify the synthesis of similar inorganic nanoparticles via multistep chemical precipitation processes.
文摘This article presents two designs,the Transaction Serial Format(TSF)and the Transaction Array Model(TAM).Together,they provide full,efficient,transaction serialization facilities for devices with limited onboard energy,such as those in an Internet of Things(IoT)network.TSF provides a compact,non-parsed,format that requires minimal processing for transaction deserialization.TAM provides an internal data structure that needs minimal dynamic storage and directly uses the elements of TSF.The simple lexical units of TSF do not require parsing.The lexical units contain enough information to allocate the internal TAM data structure efficiently.TSF generality is equivalent to XML and JSON.TSF represents any XML document or JSON object without loss of information,including whitespace.The XML equivalence provides a foundation for the performance comparisons.A performance comparison of a C reference implementation of TSF and TAM to the popular Expat XML library,also written in C,shows that TSF reduces deserialization processor time by more than 80%.
文摘针对工业机器人在高度制造领域精度不高的问题,本文提出了一种基于POE模型的工业机器人运动学参数二次辨识方法。阐述了基于指数积(Product of exponential, POE)模型的运动学误差模型构建方法,并建立基于POE误差模型的适应度函数;为实现高精度的参数辨识,提出了一种二次辨识方法,先利用改进灰狼优化算法(Improved grey wolf optimizer, IGWO)实现运动学参数误差的粗辨识,初步将Staubli TX60型机器人的平均位置误差和平均姿态误差分别从(0.648 mm, 0.212°)降低为(0.457 mm, 0.166°);为进一步提高机器人的精度性能,再通过LM(Levenberg-Marquard)算法进行参数误差的精辨识,最终将Staubli TX60型机器人平均位置误差和平均姿态误差进一步降低为(0.237 mm, 0.063°),机器人平均位置误差和平均姿态误差分别降低63.4%和70.2%。为了验证上述二次辨识方法的稳定性,随机选取5组辨识数据集和验证数据集进行POE误差模型的参数误差辨识,结果表明提出的二次辨识方法能够稳定、精确地辨识工业机器人运动学参数误差。
