A feasible method was proposed to improve the vibration intensity of screen surface via application of a new type elastic screen surface with multi degree of freedom(NTESSMDF). In the NTESSMDF, the primary robs were c...A feasible method was proposed to improve the vibration intensity of screen surface via application of a new type elastic screen surface with multi degree of freedom(NTESSMDF). In the NTESSMDF, the primary robs were coupled to the main screen structure with ends embedded into the elastomers, and the secondary robs were attached to adjacent two primary robs with elastic bands. The dynamic model of vibrating screen with NTESSMDF was established based on Lagrange's equation and the equivalent stiffnesses of the elastomer and elastic band were calculated. According to numerical simulation using the 4th order Runge-Kutta method, the vibration intensity of screen surface can be enhanced substantially with an averaged acceleration amplitude increasing ratio of 72.36%. The primary robs and secondary robs vibrate inversely in steady state, which would result in the friability of materials and avoid stoppage. The experimental results validate the dynamic characteristics with acceleration amplitude rising by62.93% on average, which demonstrates the feasibility of NTESSMDF.展开更多
Liang Qichao 's analysis of "freedom "in On Freedom is mainly focused on revealing the evolution and variation of the term "freedom "in modern Chinese society. In his view,freedom is not only a...Liang Qichao 's analysis of "freedom "in On Freedom is mainly focused on revealing the evolution and variation of the term "freedom "in modern Chinese society. In his view,freedom is not only an indispensable element of an individual's life,but also fully applicable to the course of social and historical developm ent. Liang Qichao 's liberalism originates directly from the West,but is deeply influenced by the Chinese traditional discourse system and the overwhelming reality context of saving the nation in modern tim es.What is different from Western liberalism is that the dim ensions of Liang Qichao 's freedom are developed at two levels,one is the individual level,the other is the national level. The form er has the significance of enlightenm ent,while the latter has the significance of saving lives. Enlightenm ent and salvation are not only the"double variations"of modern C hina,but also the dual responsibility of modern Chinese enlightenm ent thinkers,which is dem-onstrated in Liang Qichao 's thought of freedom.展开更多
This paper has briefly examined Marx's conception of freedom in modern industrial society. Even a rapid comparison indicates Marx says different things at different times.The emphasis shifts from,say,an initial vi...This paper has briefly examined Marx's conception of freedom in modern industrial society. Even a rapid comparison indicates Marx says different things at different times.The emphasis shifts from,say,an initial view of freedom based on a quasi-Hegelian view of radical equality and even love to freedom beyond the division of labor,then later a very different view of freedom based on a shorter working day,and so on.展开更多
Non-uniform linear array(NULA)configurations are well renowned due to their structural ability for providing increased degrees of freedom(DOF)and wider array aperture than uniform linear arrays(ULAs).These characteris...Non-uniform linear array(NULA)configurations are well renowned due to their structural ability for providing increased degrees of freedom(DOF)and wider array aperture than uniform linear arrays(ULAs).These characteristics play a significant role in improving the direction-of-arrival(DOA)estimation accuracy.However,most of the existing NULA geometries are primarily applicable to circular sources(CSs),while they limitedly improve the DOF and continuous virtual aperture for noncircular sources(NCSs).Toward this purpose,we present a triaddisplaced ULAs(Tdis-ULAs)configuration for NCS.The TdisULAs structure generally consists of three ULAs,which are appropriately placed.The proposed antenna array approach fully exploits the non-circular characteristics of the sources.Given the same number of elements,the Tdis-ULAs design achieves more DOF and larger hole-free co-array aperture than its sparse array competitors.Advantageously,the number of uniform DOF,optimal distribution of elements among the ULAs,and precise element positions are uniquely determined by the closed-form expressions.Moreover,the proposed array also produces a filled resulting co-array.Numerical simulations are conducted to show the performance advantages of the proposed Tdis-ULAs configuration over its counterpart designs.展开更多
基金Project(51221462)supported by the National Natural Science Foundation of China for Innovative Research GroupProject(20120095110001)supported by the Doctoral Fund of Ministry of Education of China+1 种基金Project supported by the Priority Academic Program Development(PAPD)of Jiangsu Higher Education Institutions,ChinaProject(CXJJ201303)supported by the Innovation Foundation of Xuyi Research and Development Center of Mining Equipment and Materials,China University of Mining and Technology,China
文摘A feasible method was proposed to improve the vibration intensity of screen surface via application of a new type elastic screen surface with multi degree of freedom(NTESSMDF). In the NTESSMDF, the primary robs were coupled to the main screen structure with ends embedded into the elastomers, and the secondary robs were attached to adjacent two primary robs with elastic bands. The dynamic model of vibrating screen with NTESSMDF was established based on Lagrange's equation and the equivalent stiffnesses of the elastomer and elastic band were calculated. According to numerical simulation using the 4th order Runge-Kutta method, the vibration intensity of screen surface can be enhanced substantially with an averaged acceleration amplitude increasing ratio of 72.36%. The primary robs and secondary robs vibrate inversely in steady state, which would result in the friability of materials and avoid stoppage. The experimental results validate the dynamic characteristics with acceleration amplitude rising by62.93% on average, which demonstrates the feasibility of NTESSMDF.
文摘Liang Qichao 's analysis of "freedom "in On Freedom is mainly focused on revealing the evolution and variation of the term "freedom "in modern Chinese society. In his view,freedom is not only an indispensable element of an individual's life,but also fully applicable to the course of social and historical developm ent. Liang Qichao 's liberalism originates directly from the West,but is deeply influenced by the Chinese traditional discourse system and the overwhelming reality context of saving the nation in modern tim es.What is different from Western liberalism is that the dim ensions of Liang Qichao 's freedom are developed at two levels,one is the individual level,the other is the national level. The form er has the significance of enlightenm ent,while the latter has the significance of saving lives. Enlightenm ent and salvation are not only the"double variations"of modern C hina,but also the dual responsibility of modern Chinese enlightenm ent thinkers,which is dem-onstrated in Liang Qichao 's thought of freedom.
文摘This paper has briefly examined Marx's conception of freedom in modern industrial society. Even a rapid comparison indicates Marx says different things at different times.The emphasis shifts from,say,an initial view of freedom based on a quasi-Hegelian view of radical equality and even love to freedom beyond the division of labor,then later a very different view of freedom based on a shorter working day,and so on.
基金supported by the National Natural Science Foundation of China(62031017,61971221)the Fundamental Research Funds for the Central Universities of China(NP2020104)。
文摘Non-uniform linear array(NULA)configurations are well renowned due to their structural ability for providing increased degrees of freedom(DOF)and wider array aperture than uniform linear arrays(ULAs).These characteristics play a significant role in improving the direction-of-arrival(DOA)estimation accuracy.However,most of the existing NULA geometries are primarily applicable to circular sources(CSs),while they limitedly improve the DOF and continuous virtual aperture for noncircular sources(NCSs).Toward this purpose,we present a triaddisplaced ULAs(Tdis-ULAs)configuration for NCS.The TdisULAs structure generally consists of three ULAs,which are appropriately placed.The proposed antenna array approach fully exploits the non-circular characteristics of the sources.Given the same number of elements,the Tdis-ULAs design achieves more DOF and larger hole-free co-array aperture than its sparse array competitors.Advantageously,the number of uniform DOF,optimal distribution of elements among the ULAs,and precise element positions are uniquely determined by the closed-form expressions.Moreover,the proposed array also produces a filled resulting co-array.Numerical simulations are conducted to show the performance advantages of the proposed Tdis-ULAs configuration over its counterpart designs.
