As one of the most important methods for machining process with high accuracy,ultra-precision grinding is widely used in fields such as aerospace,automotive and mold,etc.Simultaneously,it is common that wheel and spin...As one of the most important methods for machining process with high accuracy,ultra-precision grinding is widely used in fields such as aerospace,automotive and mold,etc.Simultaneously,it is common that wheel and spindle axis do not coincide with each other due to wheel settings,machining errors and so on.This could result in the generation of wheel runout,which may reduce the machining surface's quality.In this paper,combining this phenomenon,an analytic algorithm method for the multi-axis grinding process is introduced according to the envelope theory.After that,the accuracy of this method is verified.Two experiments are carried out on a 5-axis machining center.The artificial runout is set up and calculated utilizing the least square method.Finally,using the presented method,two examples with and without runout are introduced to illustrate the validation of the proposed model.The error due to the runout effect is also analyzed.展开更多
Human cytomegalovirus virions contain three major glycoprotein complexes (gC I, II, III), all of which are required for CMV infectivity. These complexes also represent major antigenic targets for anti-viral immune res...Human cytomegalovirus virions contain three major glycoprotein complexes (gC I, II, III), all of which are required for CMV infectivity. These complexes also represent major antigenic targets for anti-viral immune responses. The gC II complex consists of two glycoproteins, gM and gN. In the current study, DNA vaccines expressing the murine cytomegalovirus (MCMV) homologs of the gM and gN proteins were evaluated for protection against lethal MCMV infection in a mouse model. Humoral and cellular immune responses, spleen viral titers, and mice survival and body-weight changes were examined. The results showed that immunization with gM or gN DNA vaccine alone was not able to offer good protection, whereas co-immunization with both gM and gN induced an effective neutralizing antibody response and cellular immune response, and provided mice with complete protection against a lethal MCMV challenge. This study provides the first in vivo evidence that the gC II (gM-gN) complex may be able to serve as a protective subunit antigen for future HCMV vaccine development.展开更多
Background:Based on the principle of“joint consultation,co-building,and sharing”,with the aim of creating an energetic new model of economic growth,the Belt and Road Initiative achieves connectivity and mutual benef...Background:Based on the principle of“joint consultation,co-building,and sharing”,with the aim of creating an energetic new model of economic growth,the Belt and Road Initiative achieves connectivity and mutual benefit.However,the degree of coordinated development of innovation subjects directly affects the improvement and optimization of the Belt and Road Initiative’s strategy implementation environment,and technology efficiency needs improvement.Methods:In this study,a data envelopment analysis model based on the environmental noise elimination algorithm(traditional Chinese medicine-Belt and Road Initiative)was used to identify the technical efficiency of the traditional Chinese medicine industry of Belt and Road Initiative by eliminating the impact of environmental factors.Results:Pure technical ineffectiveness,regional impact,and environmental factors represented by policy responses have a non-linear impact on technical efficiency.The overall technical efficiency of the traditional Chinese medicine industry in the countries along the route shows a trend of annual increases,technical efficiency and scale efficiency are relatively high,and operational efficiency is influenced by the degree of response of the countries along the route and its supporting policies.Conclusion:Pure technical inefficiency is the main factor affecting total technical loss.Geographical advantage is the key factor in operational efficiency.External environmental factors have a significant influence on the operational efficiency of the traditional Chinese medicine industry.展开更多
In software defined radio (SDR), sharp filters of different bandwidth are required to fine tune the desired channel. This requires different computational resources and large number of filter coefficients. This paper ...In software defined radio (SDR), sharp filters of different bandwidth are required to fine tune the desired channel. This requires different computational resources and large number of filter coefficients. This paper proposes a continuously variable bandwidth sharp finite impulse response (FIR) filter with low distortion and low complexity. For this, a fixed length FIR filter is used with two arbitrary sampling rate converters. This system can be used for both the continuous increase as well as decrease of the effective bandwidth of a filter. The low complexity and sharpness are achieved by using the frequency-response masking (FRM) approach for the design of the fixed length FIR filter. The sharp transition width leads to maximum rejection to channel interference in SDR.展开更多
为更全面提取转子故障特征,将全矢谱和复局部均值分解(Complex local mean decomposition,CLMD)相结合,提出二元的全矢包络技术——CLMD全矢包络技术。采用正交采样技术获取转子同一截面上互相垂直方向上的振动信号,并将其组成一个复数...为更全面提取转子故障特征,将全矢谱和复局部均值分解(Complex local mean decomposition,CLMD)相结合,提出二元的全矢包络技术——CLMD全矢包络技术。采用正交采样技术获取转子同一截面上互相垂直方向上的振动信号,并将其组成一个复数信号;运用CLMD将复数信号按能量从高到低的顺序依次分离出系列复乘积函数(Complex product function,CPF),并解调出CPF的复包络;由于故障特征主要在能量较高的CPF分量中,通过全矢谱技术融合前几阶CPF分量的包络信号,得到相应的全矢包络谱。仿真的调幅-调频信号分析结果表面,较之Hilbert解调,CLMD全矢包络技术可提取隐含的调频信息,而且不存在虚假的低频谱线。转子试验台模拟的基座松动信号、碰摩信号分析结果表明,较之单源信息的包络谱,CLMD全矢包络技术提取的谱线特征更清晰、全面,而且根据全矢包络谱可有效区分基座松动引起的碰摩和单一碰摩故障。展开更多
基金supported by the National Natural Science Foundation of China(No.51605147)National Science Fund for Distinguished Young Scholars of Henan Polytechnic University(J2019-2)Young Backbone Project of Henan Polytechnic University(No.2018XQG-05)。
文摘As one of the most important methods for machining process with high accuracy,ultra-precision grinding is widely used in fields such as aerospace,automotive and mold,etc.Simultaneously,it is common that wheel and spindle axis do not coincide with each other due to wheel settings,machining errors and so on.This could result in the generation of wheel runout,which may reduce the machining surface's quality.In this paper,combining this phenomenon,an analytic algorithm method for the multi-axis grinding process is introduced according to the envelope theory.After that,the accuracy of this method is verified.Two experiments are carried out on a 5-axis machining center.The artificial runout is set up and calculated utilizing the least square method.Finally,using the presented method,two examples with and without runout are introduced to illustrate the validation of the proposed model.The error due to the runout effect is also analyzed.
基金supported by the Innovation Platform Open Fund of Hunan Provincial Education Department (11K010)a research fund from Hunan Provincial Science and Technology Development (2008TP4033-2)
文摘Human cytomegalovirus virions contain three major glycoprotein complexes (gC I, II, III), all of which are required for CMV infectivity. These complexes also represent major antigenic targets for anti-viral immune responses. The gC II complex consists of two glycoproteins, gM and gN. In the current study, DNA vaccines expressing the murine cytomegalovirus (MCMV) homologs of the gM and gN proteins were evaluated for protection against lethal MCMV infection in a mouse model. Humoral and cellular immune responses, spleen viral titers, and mice survival and body-weight changes were examined. The results showed that immunization with gM or gN DNA vaccine alone was not able to offer good protection, whereas co-immunization with both gM and gN induced an effective neutralizing antibody response and cellular immune response, and provided mice with complete protection against a lethal MCMV challenge. This study provides the first in vivo evidence that the gC II (gM-gN) complex may be able to serve as a protective subunit antigen for future HCMV vaccine development.
文摘Background:Based on the principle of“joint consultation,co-building,and sharing”,with the aim of creating an energetic new model of economic growth,the Belt and Road Initiative achieves connectivity and mutual benefit.However,the degree of coordinated development of innovation subjects directly affects the improvement and optimization of the Belt and Road Initiative’s strategy implementation environment,and technology efficiency needs improvement.Methods:In this study,a data envelopment analysis model based on the environmental noise elimination algorithm(traditional Chinese medicine-Belt and Road Initiative)was used to identify the technical efficiency of the traditional Chinese medicine industry of Belt and Road Initiative by eliminating the impact of environmental factors.Results:Pure technical ineffectiveness,regional impact,and environmental factors represented by policy responses have a non-linear impact on technical efficiency.The overall technical efficiency of the traditional Chinese medicine industry in the countries along the route shows a trend of annual increases,technical efficiency and scale efficiency are relatively high,and operational efficiency is influenced by the degree of response of the countries along the route and its supporting policies.Conclusion:Pure technical inefficiency is the main factor affecting total technical loss.Geographical advantage is the key factor in operational efficiency.External environmental factors have a significant influence on the operational efficiency of the traditional Chinese medicine industry.
文摘In software defined radio (SDR), sharp filters of different bandwidth are required to fine tune the desired channel. This requires different computational resources and large number of filter coefficients. This paper proposes a continuously variable bandwidth sharp finite impulse response (FIR) filter with low distortion and low complexity. For this, a fixed length FIR filter is used with two arbitrary sampling rate converters. This system can be used for both the continuous increase as well as decrease of the effective bandwidth of a filter. The low complexity and sharpness are achieved by using the frequency-response masking (FRM) approach for the design of the fixed length FIR filter. The sharp transition width leads to maximum rejection to channel interference in SDR.
文摘为更全面提取转子故障特征,将全矢谱和复局部均值分解(Complex local mean decomposition,CLMD)相结合,提出二元的全矢包络技术——CLMD全矢包络技术。采用正交采样技术获取转子同一截面上互相垂直方向上的振动信号,并将其组成一个复数信号;运用CLMD将复数信号按能量从高到低的顺序依次分离出系列复乘积函数(Complex product function,CPF),并解调出CPF的复包络;由于故障特征主要在能量较高的CPF分量中,通过全矢谱技术融合前几阶CPF分量的包络信号,得到相应的全矢包络谱。仿真的调幅-调频信号分析结果表面,较之Hilbert解调,CLMD全矢包络技术可提取隐含的调频信息,而且不存在虚假的低频谱线。转子试验台模拟的基座松动信号、碰摩信号分析结果表明,较之单源信息的包络谱,CLMD全矢包络技术提取的谱线特征更清晰、全面,而且根据全矢包络谱可有效区分基座松动引起的碰摩和单一碰摩故障。