A new model for the vibration isolation via pile rows consisting of infinite number of piles

2012 ◽  
Vol 37 (15) ◽  
pp. 2394-2426 ◽  
Author(s):  
Jian-Fei Lu ◽  
Dong-Sheng Jeng ◽  
Jian-Wei Wan ◽  
Ji-Sheng Zhang
1996 ◽  
Vol 3 (1) ◽  
pp. 61-67 ◽  
Author(s):  
Ye-Ping Xiong ◽  
Kong-Jie Song ◽  
Xing Ai

This article deals with the interaction between wave effects in mounts and resonances of foundations inflexible vibration isolation systems. A new model is proposed that is represented as a rigid mass supported by two linear unidirectional isolators on a flexible foundation beam, whose closed-form solutions for transmissibility and response ratio are then obtained, with which the influence of wave effects coupled with the flexibility of the foundation on the effectiveness of isolation is discussed. The wave effects on flexible isolation systems are analyzed under various parametric conditions and compared with those in rigid systems. In addition, several special cases are presented to show the transition between various limiting cases. Some approaches to control wave effects are also proposed.


2019 ◽  
Vol 25 (16) ◽  
pp. 2282-2292 ◽  
Author(s):  
Niuniu Liu ◽  
Zeyu Jin ◽  
Hongxing Hua

Two models have previously been commonly used to predict the isolation performance of a hydraulic leveraged dynamic anti-resonance vibration isolator. The models have deficiencies, however, in considering the volumetric stiffness of the isolator. In this paper, a new model is proposed to improve the accuracy by reasonably taking the volumetric stiffness into consideration. The model is validated by a carefully designed experiment. The influence of the volumetric stiffness on the isolation performance of the isolator is investigated by the validated model. The results indicate that the volumetric stiffness of the isolator and its location in a mathematical model have a significant influence on the isolation frequency and the second natural frequency of the isolator. The dependence of the volumetric stiffness on the isolation frequency, the attenuation capacity at the isolation frequency, and the bandgap of the isolator is presented. The investigation will enhance the understanding of the hydraulic leveraged dynamic anti-resonance vibration isolator, and facilitate the design and exploitation of this type of isolator in the field of vibration isolation.


1999 ◽  
Vol 121 (2) ◽  
pp. 171-178 ◽  
Author(s):  
Bruce H. Wilson ◽  
Cem Erin ◽  
Achille Messac

Vibration isolation tables find application in diverse production and research environments. The structure of a table is such that a designer is forced to compromise among design metrics such as transmissibility, force-disturbance rejection, and controller effort. As both structural and controller parameters impact these design metrics, we chose to perform simultaneous control-structure integrated design (CSID) to optimize the overall performance. We employed a new model that enhances physical insight and used physical programming as the optimization framework. We explored several design scenarios and effectively uncovered the appropriate compromises among the competing objectives. The results highlight the utility of the new model in this design context and the usefulness of physical programming in performing simultaneous CSID.


2020 ◽  
Vol 43 ◽  
Author(s):  
Aba Szollosi ◽  
Ben R. Newell

Abstract The purpose of human cognition depends on the problem people try to solve. Defining the purpose is difficult, because people seem capable of representing problems in an infinite number of ways. The way in which the function of cognition develops needs to be central to our theories.


Author(s):  
H. Akabori ◽  
K. Nishiwaki ◽  
K. Yoneta

By improving the predecessor Model HS- 7 electron microscope for the purpose of easier operation, we have recently completed new Model HS-8 electron microscope featuring higher performance and ease of operation.


Author(s):  
Bernd Tesche ◽  
Tobias Schilling

The objective of our work is to determine:a) whether both of the imaging methods (TEM, STM) yield comparable data andb) which method is better suited for a reliable structure analysis of microclusters smaller than 1.5 nm, where a deviation of the bulk structure is expected.The silver was evaporated in a bell-jar system (p 10−5 pa) and deposited onto a 6 nm thick amorphous carbon film and a freshly cleaved highly oriented pyrolytic graphite (HOPG).The average deposited Ag thickness is 0.1 nm, controlled by a quartz crystal microbalance at a deposition rate of 0.02 nm/sec. The high resolution TEM investigations (100 kV) were executed by a hollow-cone illumination (HCI). For the STM investigations a commercial STM was used. With special vibration isolation we achieved a resolution of 0.06 nm (inserted diffraction image in Fig. 1c). The carbon film shows the remarkable reduction in noise by using HCI (Fig. 1a). The HOPG substrate (Fig. 1b), cleaved in sheets thinner than 30 nm for the TEM investigations, shows the typical arrangement of a nearly perfect stacking order and varying degrees of rotational disorder (i.e. artificial single crystals). The STM image (Fig. 1c) demonstrates the high degree of order in HOPG with atomic resolution.


2005 ◽  
Vol 173 (4S) ◽  
pp. 140-141
Author(s):  
Mariana Lima ◽  
Celso D. Ramos ◽  
Sérgio Q. Brunetto ◽  
Marcelo Lopes de Lima ◽  
Carla R.M. Sansana ◽  
...  

Author(s):  
Thorsten Meiser

Stochastic dependence among cognitive processes can be modeled in different ways, and the family of multinomial processing tree models provides a flexible framework for analyzing stochastic dependence among discrete cognitive states. This article presents a multinomial model of multidimensional source recognition that specifies stochastic dependence by a parameter for the joint retrieval of multiple source attributes together with parameters for stochastically independent retrieval. The new model is equivalent to a previous multinomial model of multidimensional source memory for a subset of the parameter space. An empirical application illustrates the advantages of the new multinomial model of joint source recognition. The new model allows for a direct comparison of joint source retrieval across conditions, it avoids statistical problems due to inflated confidence intervals and does not imply a conceptual imbalance between source dimensions. Model selection criteria that take model complexity into account corroborate the new model of joint source recognition.


1986 ◽  
Vol 31 (2) ◽  
pp. 108-109
Author(s):  
Alexandra G. Kaplan
Keyword(s):  

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