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进给系统刚度对数控机床失动量影响 被引量:1
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作者 廖德岗 《制造技术与机床》 CSCD 北大核心 1999年第11期23-23,54,共2页
关键词 数控机床 刚度 失动量 进结系统
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A new marine propulsion system 被引量:1
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作者 HAN Wei-shi, LIU Tao School of Power and Nuclear Energy Engineering, Harbin Engineering University, Harbin 150001, China 《Journal of Marine Science and Application》 2003年第1期30-34,共5页
A new marine propulsion system is proposed . A small liquid sodium cooled reactor acts as prime mover; alkali-metal thermal-to-electric conversion ( AMTEC) cells are employed to convert the heat energy to electricity;... A new marine propulsion system is proposed . A small liquid sodium cooled reactor acts as prime mover; alkali-metal thermal-to-electric conversion ( AMTEC) cells are employed to convert the heat energy to electricity; superconducting magneto-hydrodynamic thruster combined with spray-water thruster works as pr opulsion. The configuration and characteristics of this system are described. Such a nuclear-powered propulsion system is not only free of noise, but also has high reliability and efficiency. It would be a preferable propulsion system for ships in the future. 展开更多
关键词 propulsion system liquid sodium cooled reactor AMTEC THRUSTER
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Khedivial Cairo: An Evolved Metabolism
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作者 Eman Mamdouh Abdel Sabour Stephen Luoni 《Journal of Civil Engineering and Architecture》 2013年第5期616-625,共10页
Metabolism such as Cairo evolves rabidly, to transform existing urban spaces. The result of transformation process may lead to the loss of the original space qualities. Opera and Ataba squares are junction space which... Metabolism such as Cairo evolves rabidly, to transform existing urban spaces. The result of transformation process may lead to the loss of the original space qualities. Opera and Ataba squares are junction space which is one of these urban spaces that meanwhile is suffering from this process. This junction space is between two unique urban structures Fatima Cairo and Down town Cairo. This urban structure needs to be a grand civic expression of the 19th century urban system with the new energies of the functionalist city. This Gordian knot of elevated highways, congested surface roads, extensive automobile parking and sprawling informal markets will be integrated into a new open space system that optimizes the city's intensified energies. This paper discusses urban structure transformation of the junction space urban structure timeline. Ending with a proposal finally transforms this space into a sustainable urban development. 展开更多
关键词 Urban spaces Khedivial Cairo sustainable urban development district transformation.
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Diversity and Evolution of Inflorescences in Celastrales
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作者 Ivan A. Savinov 《Journal of Life Sciences》 2013年第2期145-152,共8页
Inflorescences structures in context of their evolution have been conducted for 60 genera and 170 species of Celastrales (according to APG (Angiosperm Phylogeny Group) III 2009, almost 60% of genera and 15% of spec... Inflorescences structures in context of their evolution have been conducted for 60 genera and 170 species of Celastrales (according to APG (Angiosperm Phylogeny Group) III 2009, almost 60% of genera and 15% of species from this taxon of the world flora). There are two big groups of inflorescences in Celastrales-intercalary (more often) and terminal. For many genera of Celastrales both types of inflorescences can be observed, although the frequency of their occurrence varies. There is an important difference between two types of inflorescences: character of completion of the main axis (the terminal flower present or absent). Flower opening can be in basipetal (Celastraceae, Brexia) or acropetal (Stackhousiaceae) order. Partial inflorescence types included: simple, compound or umbrellate dichasia, spike, raceme, thyrse. Simple flowers of Parnassia are large, nested on long reproductive shoots, emerging from a rosette, with amplexicaule leaf. 展开更多
关键词 Celastrales CELASTRACEAE Brexia Parnassia Stackhousiaceae INFLORESCENCES structure and development ofinflorescences molecular data.
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Cellular structure of detonation utilized in propulsion system 被引量:2
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作者 ZHANG XuDong FAN BaoChun +1 位作者 GUI MingYue PAN ZhenHua 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2012年第10期1915-1924,共10页
How to confine a detonation in a combustor is a key issue of detonation applications in propulsion systems.Based on achieving schemes,detonations applied in the combustor,including pulse detonation wave(PDW),oblique d... How to confine a detonation in a combustor is a key issue of detonation applications in propulsion systems.Based on achieving schemes,detonations applied in the combustor,including pulse detonation wave(PDW),oblique detonation wave(ODW) and rotating detonation wave(RDW),are different from that described by the classic CJ theory in fine structures and its self-sustaining mechanisms.In this work,the cellular structures and flow fields of ODW and RDW were obtained numerically,and the fundamental characteristics and self-sustaining mechanisms of the detonations were analyzed and discussed.ODW front consists of three parts:the ZND-like front,the single-headed triple point front and the dual-headed triple point front.Cellular structures of RDW are heterogeneous,and the cell size near the outer wall is smaller than that near the inner wall. 展开更多
关键词 propulsion system fundamental characteristics self-sustaining mechanisms classic CJ theory
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Flow Field Measurements in the Cavity of a Trapped Vortex Combustor Using PIV 被引量:6
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作者 Zhang Rongchun Fan Weijun 《Journal of Thermal Science》 SCIE EI CAS CSCD 2012年第4期359-367,共9页
The experimental research on cavity flow field plays an important part in the structural design and optimization study of trapped vortex combustor (TVC). Many of the previous flow field experiments were conducted in t... The experimental research on cavity flow field plays an important part in the structural design and optimization study of trapped vortex combustor (TVC). Many of the previous flow field experiments were conducted in the cold condition instead of during combustion. This paper adopting PIV system and Lambda-2 vortex criterion in-vestigates the influence of various factors, such as equivalent ratio in the cavity, air intake parameter in the cavity, mainstream air intake parameter and mainstream holder structure, on cavity flow field for a TVC using methane as the fuel. The experimental research showed that cold-condition flow field differed from the combustion flow field, in terms of either vortex core position or vortex structure. Mainstream air intake velocity and cavity air intake velocity affected the flow field structure. U-type and V-type mainstream holders had significant influence on cavity flow field. 展开更多
关键词 trapped vortex combustor flow field PIV METHANE EXPERIMENT
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Evolutionary algorithm based on dynamical structure of membrane systems in uncertain environments
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作者 Chuang Liu Linan Fan 《International Journal of Biomathematics》 2016年第2期1-16,共16页
In this paper, a new evolutionary algorithm based on a membrane system is proposed to solve the dynamic or uncertain optimization problems. The proposed algorithm employs objects, a dynamical membrane structure and se... In this paper, a new evolutionary algorithm based on a membrane system is proposed to solve the dynamic or uncertain optimization problems. The proposed algorithm employs objects, a dynamical membrane structure and several reaction rules of the membrane systems. The object represents a candidate solution of the optimization problems. The dynamical structure consists of the nested membranes where a skin membrane contains several membranes, which is useful for the proposed algorithm that finds optimal solutions. The reaction rules are designed to locate and track the optimal solutions of the dynamic optimization problems (DOPs), which are inspired by processing the chemical compounds in the region of cellular membranes. Experimental study is conducted based on the moving peaks benchmark to evaluate the performance of the proposed algorithm in comparison with three state-of-the-art dynamic optimization algorithms. The results indicate the proposed algorithm is effective to solve the DOPs. 展开更多
关键词 Membrane systems membrane algorithm dynamic optimization problems.
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通信枢纽楼能耗运行分析研究 被引量:2
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作者 樊春锋 伍建萍 《电信工程技术与标准化》 2016年第5期89-92,共4页
如何在业务量不断增加,电源容量无法扩容的情况下,更好地解决供电能力紧张、机房装机位不足、机房散热等问题,是本论文的研究意义所在。本文通过对S省通信枢纽楼能耗运行分析,给出以上难点的合理化建议和建设指导原则。
关键词 枢纽楼 变压器 能耗 红色预警 搬迁
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