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非线性周期结构动力学与波动调控研究进展
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作者 高鹏林 龚凌云 +5 位作者 王国旭 罗宇 朱俊喆 高昊 马海斌 瞿叶高 《力学进展》 北大核心 2025年第3期567-641,共75页
周期结构是构建自然界和人类工程结构的一种重要形式,平移对称性引起的Bloch调制作用赋予其独特的能带结构和丰富的时/频域动力学特性,为弹性波/声波传播调控、新型声功能器件设计、振动与噪声控制等提供了新思路.非线性效应可以突破线... 周期结构是构建自然界和人类工程结构的一种重要形式,平移对称性引起的Bloch调制作用赋予其独特的能带结构和丰富的时/频域动力学特性,为弹性波/声波传播调控、新型声功能器件设计、振动与噪声控制等提供了新思路.非线性效应可以突破线性理论框架的束缚,能够增强甚至拓展人工周期结构的功能.但非线性周期系统在单胞结构设计和建模分析方面存在诸多困难,也面临时空平移对称性破缺、非线性响应特性及机理复杂等深层次科学难题,给非线性周期结构动力学设计与实际应用带来挑战.针对上述问题,学者们融合力学、声学、材料学和能带物理等多学科研究方法开展了一些卓有成效的研究,本文旨在及时总结非线性周期结构动力学和波动调控领域的重要研究进展,梳理研究中存在的不足之处和关键难题,凝聚力量,促进该领域的深入发展.首先,归纳了力学周期结构非线性效应来源、单胞结构设计方法、非线性周期结构动力学建模与分析方法;之后,综述了非线性周期结构在通带、带隙和能量局域束缚等方面的主要特性,着重介绍了非线性导致的能带频移、模式耦合、低频宽带拓展和带隙内波动模式局域束缚等丰富动力学现象,梳理了非线性周期结构在波调控装置和减振降噪设计方面的一些应用探索.最后,针对现有研究存在的一些不足和关键难题,展望了未来理论研究和应用探索亟需关注的若干发展方向. 展开更多
关键词 非线性周期结构 动力学设计 非线性振动 振动控制 波动调控
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装饰艺术及装饰造型的基本特征 被引量:4
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作者 曲艺民 秦天星 +3 位作者 qu Yimin Qin Tianxing 《昌吉学院学报》 2005年第3期22-24,共3页
作为一种相对独立、包容面又十分广泛的艺术形态或创作体裁,装饰艺术以实用为目的,以形式表现和审美表达为核心,兼备了实用与欣赏、具象与抽象、表物与寓意等方面的特点。装饰艺术具有形式结构上的内在规定性,其概念也随着时代的发展而... 作为一种相对独立、包容面又十分广泛的艺术形态或创作体裁,装饰艺术以实用为目的,以形式表现和审美表达为核心,兼备了实用与欣赏、具象与抽象、表物与寓意等方面的特点。装饰艺术具有形式结构上的内在规定性,其概念也随着时代的发展而得以不断地拓展和延伸。装饰造型是装饰艺术的物化和载体,是装饰艺术的视觉化、形象化。由于其功能及审美价值的文化取向形成了装饰艺术的精神内涵,从而在造型方式上体现出鲜明的艺术特征。装饰艺术是人类文化艺术领域中重要的组成部分,具有广泛的实用价值和艺术欣赏价值。 展开更多
关键词 装饰艺术 装饰造型 艺术形态 基本特征
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Evidence for water exchange between the South China Sea and the Pacific Ocean through the Luzon Strait 被引量:43
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作者 qu Tangdong(曲堂栋) 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2002年第2期175-185,共11页
An analysis of historical oxygen data provides evidence on the water exchange between theSouth China Sea (SCS) and the Pacific Ocean (PO). In the vicinity of the Luzon Strait (LS) , the dissolved oxygen concentration ... An analysis of historical oxygen data provides evidence on the water exchange between theSouth China Sea (SCS) and the Pacific Ocean (PO). In the vicinity of the Luzon Strait (LS) , the dissolved oxygen concentration of sea water is found to be lower on the Pacific side than on the SCS side at depths between 700 and 1500 m (intermediate layer) , while the situation is reversed above 700 m (upper layer) and below 1 500 m (deep layer). The evidence suggests that water exits the SCS in the intermediate layer but enters it from the Pacific in both the upper and the deep layers, supporting the earlier speculation that the Luzon Strait transport has a sandwiched structure in the vertical. Within the SCS basin, the oxygen distribution indicates widespread vertical movement, including the upwelling in the intermediate layer and the downwelling in the deep layer. 展开更多
关键词 Water exchange the South China Sea the Pacific Ocean the Luzon Strait
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Enhancement Effects of Three Rare Earth Elements on the Growth of Chaetoceros Mulleri 被引量:1
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作者 qu Keming(曲克明) +1 位作者 Xin Fuyan(辛福言) 《Marine Science Bulletin》 CAS 2001年第2期83-88,共6页
Enhancement effects of rare earth elements on the growth of Chaetoceros mulleri is studied in this paper. The results show that all of the light, middle and heavy rare earth elements have similar enhancement effect on... Enhancement effects of rare earth elements on the growth of Chaetoceros mulleri is studied in this paper. The results show that all of the light, middle and heavy rare earth elements have similar enhancement effect on the growth of Chaetoceros mulleri, with the beneficial concentrations of La, Gd and Yb being 7.28~87.40 μ mol/L, 6.36~57.23 μ mol/L and 5.78~17.34 μ mol/L. The optimum concentrations of La, Gd and Yb are 7.28 ~50.98 μ mol/L,31.80~44.52 μ m ol/L and 5.78~17.34 1μ mol/L, respectively. When the concentrations of La, Gd and Yb are 7.28~87.40 μ mol/L, 6.36~57.23 μ mol/L and 5.78~ 17,34 μ mol/L, the concentrations of chlorophyll have increased by 9.3~47.0%, 33.4~44.3%, and 36.5~40.3%, respectively as compared with the control group. The mechanism of enhancement of rare earth elements on the growth ot Chaetoceros mulleri is also discussed in this paper. 展开更多
关键词 RARE EARTH element CHAETOCEROS mulleri ENHANCEMENT
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Development of a distribution management system in refinery industry
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作者 王成恩 Liu +2 位作者 Zhen qu Rongxia 《High Technology Letters》 EI CAS 2006年第1期47-50,共4页
Developing an information system for managing the product distribution in a refinery demands sophisticated design solutions. First, organization models are created to describe the structural relationships among employ... Developing an information system for managing the product distribution in a refinery demands sophisticated design solutions. First, organization models are created to describe the structural relationships among employees and the ways in which they will use the information system. Second, function models are created to hierarchically describe how sales, transports, deliveries and vehicles are managed. Thirdly, an information model is built to represent the data entities and their dynamic interactions. Based on the system design, a distribution management system is developed and implemented in a refinery, which has considerably increased the distribution management efficiency and effectiveness. 展开更多
关键词 Design DYNAMICS Hierarchical systems Industrial management Mathematical models Structures (built objects)
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A New Method of Hardening Inner Wall of Long Pipe
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作者 王扬 Deng +2 位作者 Zhongquan qu Cunjing 《High Technology Letters》 EI CAS 2001年第2期80-82,共3页
A new laser inner wall hardening method for long pipe mas introduced. The system combines laser surface hardening with robot moving in pipeline. Some craft experiments have been done with this system and optimum param... A new laser inner wall hardening method for long pipe mas introduced. The system combines laser surface hardening with robot moving in pipeline. Some craft experiments have been done with this system and optimum parameters of laser hardening have been found. 展开更多
关键词 Laser hardening Long pipe YAG laser
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