A Softening–Hardening Nanomechanics Theory for the Static and Dynamic Analyses of Nanorods and Nanobeams: Doublet Mechanics

2021 ◽  
pp. 43-78
Author(s):  
Ufuk Gul ◽  
Metin Aydogdu
Keyword(s):  
Doublet Mechanics ◽  
Dynamic Analyses

Confounding contaminants in mass spectrometric reaction monitoring

2018 ◽  
Author(s):  
Gilian T. Thomas ◽  
Landon MacGillivray ◽  
Natalie L. Dean ◽  
Rhonda L. Stoddard ◽  
Lars Yunker ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Mass Spectrometric ◽  
Negative Ion ◽  
Reaction Monitoring ◽  
Schlenk Flask ◽  
Dynamic Analyses ◽  
Rubber Septa ◽  
Negative Ion Mode ◽  
Mode A

<p>Reactions carried out in the presence of rubber septa run the risk of additives being leached out by the solvent. Normally, such species are present at low enough levels that they do not interfere with the reaction significantly. However, when studying reactions using sensitive methods such as mass spectrometry, the appearance of even trace amounts of material can confuse dynamic analyses of reactions. A wide variety of additives are present in rubber along with the polymer: antioxidants, dyes, detergent, and vulcanization agents, and these are all especially problematic in negative ion mode. A redesigned Schlenk flask for pressurized sample infusion (PSI) is presented as a means of practically eliminating the presence of contaminants during reaction analyses.</p>

Dynamic Analyses of the Mortar Dragster Tab Mechanism

1998 ◽  
Author(s):  
John A. Condon ◽  
Michael S. Hollis
Keyword(s):  
Dynamic Analyses

The Effect of Type and Height of Piers on the Seismic Behavior of Reinforced Concrete Bridges

2019 ◽  
Vol 41 ◽  
pp. 79-87 ◽  
Author(s):  
Mohamed Cherif Djemai ◽  
Mahmoud Bensaibi ◽  
Fatma Zohra Halfaya
Keyword(s):  
Reinforced Concrete ◽  
Structural Parameters ◽  
Strong Motion ◽  
Concrete Bridges ◽  
Geometrical Parameters ◽  
Girder Bridges ◽  
Building Research Institute ◽  
Reinforced Concrete Bridges ◽  
Dynamic Analyses ◽  
Strong Motion Database

Bridges are commonly used lifelines; they play an important role in the economic activity of a city or a region and their role can be crucial in a case of a seismic event since they allow the arrival of the first aid. Reinforced concrete (RC) bridges are worldwide used type view their durability, flexibility and economical cost. In fact, their behavior under seismic loading was the aim of various studies. In the present study the effect of two structural parameters i.e. the height and the type of piers of reinforced concrete bridges on seismic response is investigated. For that reason, different multi-span continuous girder bridges models with various geometrical parameters are considered. Then, non-linear dynamic analyses are performed based on two types of piers which are: multiple columns bent and wall piers with varying heights. In this approach, a serie of 40 ground motions records varying from weak to strong events selected from Building Research Institute (BRI) strong motion database are used including uncertainty in the soil and seismic characteristics. Modelling results put most emphasis on the modal periods and responses of the top pier displacements, they show the influence of the considered parameters on the behavior of such structures and their impact on the strength of reinforced concrete bridges.

Verification of displacement-based adaptive pushover through multi-ground motion incremental dynamic analyses

2009 ◽  
Vol 31 (8) ◽  
pp. 1789-1799 ◽  
Author(s):  
Barbara Ferracuti ◽  
Rui Pinho ◽  
Marco Savoia ◽  
Roberto Francia
Keyword(s):  
Ground Motion ◽  
Dynamic Analyses ◽  
Displacement Based ◽  
Adaptive Pushover

Dynamics Characteristics for Contact Surface of Machine Tool

2014 ◽  
Vol 538 ◽  
pp. 91-94
Author(s):  
Wei Ping Luo
Keyword(s):  
Machine Tool ◽  
Dynamic Characteristics ◽  
Contact Surface ◽  
Dynamic Performance ◽  
Virtual Prototype ◽  
Prototype Model ◽  
Ansys Software ◽  
Dynamic Analyses ◽  
Contact Surfaces

A virtual prototype model of Machine Tool has been constructed by using the Pro/E software and the ANSYS software. Considering the effects of contact surfaces, dynamic analyses of Machine Tool are studied. The effects of contact surfaces on the dynamic characteristics of machine tool are studied. So that the purpose predicting and evaluating synthetically the machine tool dynamic performance without a physical sample can be achieved.

Dynamics of a Two-DOF Parallel Pointing Mechanism

2005 ◽  
Author(s):  
Alessandro Cammarata ◽  
Rosario Sinatra
Keyword(s):  
Numerical Simulation ◽  
Parallel Mechanism ◽  
Inverse Dynamics ◽  
Kinematic Model ◽  
Degree Of Freedom ◽  
Numerical Examples ◽  
Proposed Model ◽  
Dynamic Analyses ◽  
Moving Platform ◽  
Two Degree Of Freedom

This paper presents kinematic and dynamic analyses of a two-degree-of-freedom pointing parallel mechanism. The mechanism consists of a moving platform, connected to a fixed platform by two legs of type PUS (prismatic-universal-spherical). At first a simplified kinematic model of the pointing mechanism is introduced. Based on this proposed model, the dynamics equations of the system using the Natural Orthogonal Complement method are developed. Numerical examples of the inverse dynamics results are presented by numerical simulation.

scholarly journals Numerical Analyses of Earthquake Induced Liquefaction and Deformation Behaviour of an Upstream Tailings Dam

2017 ◽  
Vol 2017 ◽  
pp. 1-12 ◽  
Author(s):  
Muhammad Auchar Zardari ◽  
Hans Mattsson ◽  
Sven Knutsson ◽  
Muhammad Shehzad Khalid ◽  
Maria V. S. Ask ◽  
...  
Keyword(s):  
Finite Element ◽  
Seismic Event ◽  
Deformation Behaviour ◽  
Ground Surface ◽  
Tailings Dam ◽  
Limited Extent ◽  
Northern Sweden ◽  
Finite Element Program ◽  
Dynamic Analyses ◽  
Element Program

Much of the seismic activity of northern Sweden consists of micro-earthquakes occurring near postglacial faults. However, larger magnitude earthquakes do occur in Sweden, and earthquake statistics indicate that a magnitude 5 event is likely to occur once every century. This paper presents dynamic analyses of the effects of larger earthquakes on an upstream tailings dam at the Aitik copper mine in northern Sweden. The analyses were performed to evaluate the potential for liquefaction and to assess stability of the dam under two specific earthquakes: a commonly occurring magnitude 3.6 event and a more extreme earthquake of magnitude 5.8. The dynamic analyses were carried out with the finite element program PLAXIS using a recently implemented constitutive model called UBCSAND. The results indicate that the magnitude 5.8 earthquake would likely induce liquefaction in a limited zone located below the ground surface near the embankment dikes. It is interpreted that stability of the dam may not be affected due to the limited extent of the liquefied zone. Both types of earthquakes are predicted to induce tolerable magnitudes of displacements. The results of the postseismic slope stability analysis, performed for a state after a seismic event, suggest that the dam is stable during both the earthquakes.

Design and analysis of a novel seven-bar mechanical servo press with dual motors inputs

2016 ◽  
Vol 231 (20) ◽  
pp. 3855-3865
Author(s):  
Chen Liu ◽  
Sheng-Dun Zhao ◽  
Jing-Xiang Li
Keyword(s):  
Metal Forming ◽  
Theoretical Study ◽  
High Capacity ◽  
High Ratio ◽  
Measured Data ◽  
Servo Motor ◽  
Symmetric Structure ◽  
Servo Press ◽  
The Press ◽  
Dynamic Analyses

This paper proposes a novel high capacity servo press system with two servo motor inputs and high ratio force amplifier mechanism for metal forming. First, the press structure was expressed. The force amplifier was made of seven-bar mechanism which possesses quick-return character and high ratio force amplifier. The symmetric structure balanced the force in horizontal direction, and dispersed the forces on two transmission routes. In theoretical study of the new structure, kinematic and dynamic analyses were obtained by examining the geometry of the structure. The performance of press was discussed by example demonstration. Finally, the kinematic experiments and metal forming experiments were carried out on the prototype machine by using grating scale system. The measured data match the theoretical calculation well, which validates the feasibility of this new press mechanism.

Sign in / Sign up

Export Citation Format

Share Document