Five Position Triad Synthesis With Applications to Four- and Six-Bar Mechanisms

1993 ◽  
Vol 115 (2) ◽  
pp. 262-268 ◽  
Author(s):  
T. Subbian ◽  
D. R. Flugrad
Keyword(s):  
Continuation Method ◽  
Solution Procedure ◽  
Motion Generation

The displacement equations for trials with motion generation and prescribed timing capabilities are developed and cast in polynomial forms. These equations are solved for five precision points using a continuation method. A detailed description of the method used to generate the solution curves is provided in the paper. Two infinities of solutions can be obtained for the problem under consideration as we are solving four equations in six unknowns. The solution procedure discussed is applied to synthesize a four-bar function generating mechanisms and a six-bar mechanism.

Six and Seven Position Triad Synthesis Using Continuation Methods

1994 ◽  
Vol 116 (2) ◽  
pp. 660-665 ◽  
Author(s):  
T. Subbian ◽  
D. R. Flugrad
Keyword(s):  
Finite Number ◽  
Continuation Method ◽  
Synthesis Problem ◽  
Continuation Methods ◽  
Path Generation ◽  
Motion Generation ◽  
Number Of Solutions ◽  
Position Synthesis

A continuation method is used for the synthesis of triads for motion generation with prescribed timing applications. The procedure is applied to solve both six and seven position synthesis problems. Triad Burmester curves are generated for the six position synthesis problem and an eight-bar mechanism is designed to illustrate the procedure. For the seven position synthesis problem, a finite number of solutions are obtained. A geared five-bar, seven position path generation example is considered.

On a Solution Procedure to Synthesize Non-Smooth Path Generating Compliant Mechanisms With Self Contact

2010 ◽  
Author(s):  
B. V. S. Nagendra Reddy ◽  
Anupam Saxena
Keyword(s):  
Large Deformation ◽  
Elastic Deformation ◽  
Optimum Design ◽  
Compliant Mechanisms ◽  
Compliant Mechanism ◽  
Solution Procedure ◽  
Motion Generation ◽  
Contact Sites ◽  
Smooth Path ◽  
Single Piece

A contact-aided compliant mechanism (CCM) is a single piece flexible continuum that uses the contact interactions between different portions in addition to the elastic deformation. Our work deals with the design of contact aided compliant mechanisms with initially curved frame elements to trace more complex and non smooth paths. We can achieve these kinematic tasks by using partially compliant mechanisms as well. But the presence of hinges is a disadvantage in terms of increased friction, backlash, need for lubrication, noise and vibrations. In this paper, we propose an automated procedure to obtain the optimum design of large deformation CCMs. Through commercial software, we simulate the formation of pseudo hinges at contact sites that get formed dynamically as the mechanism deforms. By appropriately positioning these pseudo hinges, i.e., by designing a suitable CCM, the aim, in general, is to achieve a variety of function, path and motion generation characteristics via single piece continua.

A Heuristic Solution Procedure to Minimize \[Tmacr] on a Single Machine

1989 ◽  
Vol 40 (3) ◽  
pp. 293-297 ◽  
Author(s):  
T D Fry ◽  
L Vicens ◽  
K Macleod ◽  
S Fernandez
Keyword(s):  
Single Machine ◽  
Solution Procedure ◽  
Heuristic Solution

Optimal Inventory Policies for Price and Time Sensitive Demand under Advertisement

2020 ◽  
Vol 13 ◽  
Author(s):  
Nita Shah ◽  
Ekta Patel ◽  
Kavita Rabari
Keyword(s):  
Cycle Time ◽  
Quadratic Function ◽  
Solution Procedure ◽  
Vital Role ◽  
Optimal Number ◽  
Deteriorating Items ◽  
Marginal Effect ◽  
Selling Price ◽  
Total Profit ◽  
Back Order

Aims: This article analyzes an inventory system for deteriorating items. The demand is quadratic function of time and is dependent on time, price and advertisement. Shortages are allowed and partially backlogged. Background: Demand and pricing are the two most crucial factors in inventory policy for any business to be successful. In today’s era of competitive circumstances, any product is promoted through advertisement, which plays a vital role in changing the demand pattern among the community. The marketing and demonstration of an item by time-to-time with fashionable advertisements through well-known media such as TV, radio, newspaper, magazine, etc. However, this idea is not always true for some goods like wheat, vegetables, fruits, food grains, medicines and other perishable goods due to their deteriorating nature and this in turn decreases demand for such goods. Deterioration may define as decay, damage, spoilage, evaporation, obsolescence, pilferage. Hence, deterioration effect is a major part in inventory control theory. So in this article demand rate is considered to be a function of selling price, time and occurrence of advertisement instantaneously. Objective: A solution procedure is obtained to find optimal number of price changes and optimal selling price to maximize the total profit. Method: Classical Optimization. Result: From the sensitivity analysis table, it can be seen that the optimal profit is highly sensible to advertisement coefficient and purchase cost. With an increment in rate of deterioration, selling price decreases. Scale demand has reasonable effect on cycle time and selling price. When the value of increase, the cycle length and profit goes on decreasing. Growth in profit is observed if we increase parameter b, higher will be the profit. Price elasticity is sensible parameter with respect to selling price. If backlogging rate increases, the profit will decreases. The inventory parameters holding cost, back order cost and lost sale cost have marginal effect on total profit. Conclusion: In this article, an inventory model is proposed for deteriorating items with variable demand depends upon the advertisement, selling price of the item and time. Shortages are allowed and partially backlogged and backlogging rate depends on the waiting time for the next replenishment. From this article, we can conclude that the parameters are insensible with respect to optimal profit, cycle time and selling price and rest of the parameters have practical output on total profit.

Effects of nonlinear interactions of flexural modes on the performance of a beam autoparametric vibration absorber

2019 ◽  
Vol 26 (7-8) ◽  
pp. 459-474
Author(s):  
Saeed Mahmoudkhani ◽  
Hodjat Soleymani Meymand
Keyword(s):  
Frequency Response ◽  
Internal Resonance ◽  
Continuation Method ◽  
Harmonic Balance Method ◽  
Vibration Absorber ◽  
Primary System ◽  
Lumped Mass ◽  
Response Curves ◽  
Internal Resonances ◽  
The One

The performance of the cantilever beam autoparametric vibration absorber with a lumped mass attached at an arbitrary point on the beam span is investigated. The absorber would have a distinct feature that in addition to the two-to-one internal resonance, the one-to-three and one-to-five internal resonances would also occur between flexural modes of the beam by tuning the mass and position of the lumped mass. Special attention is paid on studying the effect of these resonances on increasing the effectiveness and extending the range of excitation amplitudes at which the autoparametric vibration absorber remains effective. The problem is formulated based on the third-order nonlinear Euler–Bernoulli beam theory, where the assumed-mode method is used for deriving the discretized equations of motion. The numerical continuation method is then applied to obtain the frequency response curves and detect the bifurcation points. The harmonic balance method is also employed for detecting the type of internal resonances between flexural modes by inspecting the frequency response curves corresponding to different harmonics of the response. Parametric studies on the performance of the absorber are conducted by varying the position and mass of the lumped mass, while the frequency ratio of the primary system to the first mode of the beam is kept equal to two. Results indicated that the one-to-five internal resonance is especially responsible for the considerable enhancement of the performance.

scholarly journals Lorentz force induced shear waves for magnetic resonance elastography applications

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Guillaume Flé ◽  
Guillaume Gilbert ◽  
Pol Grasland-Mongrain ◽  
Guy Cloutier
Keyword(s):  
Magnetic Resonance ◽  
Shear Wave ◽  
Lorentz Force ◽  
Wave Attenuation ◽  
Shear Waves ◽  
Estimation Method ◽  
Biological Tissues ◽  
Magnetic Resonance Elastography ◽  
Motion Generation ◽  
Wave Source

AbstractQuantitative mechanical properties of biological tissues can be mapped using the shear wave elastography technique. This technology has demonstrated a great potential in various organs but shows a limit due to wave attenuation in biological tissues. An option to overcome the inherent loss in shear wave magnitude along the propagation pathway may be to stimulate tissues closer to regions of interest using alternative motion generation techniques. The present study investigated the feasibility of generating shear waves by applying a Lorentz force directly to tissue mimicking samples for magnetic resonance elastography applications. This was done by combining an electrical current with the strong magnetic field of a clinical MRI scanner. The Local Frequency Estimation method was used to assess the real value of the shear modulus of tested phantoms from Lorentz force induced motion. Finite elements modeling of reported experiments showed a consistent behavior but featured wavelengths larger than measured ones. Results suggest the feasibility of a magnetic resonance elastography technique based on the Lorentz force to produce an shear wave source.

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