scholarly journals A New Approach on Vibrating Horns Design

2017 ◽  
Vol 2017 ◽  
pp. 1-12 ◽  
Author(s):  
Maria Violeta Guiman ◽  
Ioan Călin Roșca
Keyword(s):  
Optimization Design ◽  
Nodal Point ◽  
Optimization Method ◽  
Cross Sectional Area ◽  
Point Of View ◽  
Sectional Area ◽  
Cross Sectional ◽  
New Approach ◽  
Frequency Maximum ◽  
Predicted Values

An optimization method of the vibrating horns is presented considering the smallest action principle and the attached cutting tool mass. The model is based on Webster’s wave propagation equation and as an objective function the minimization of the volume in structural equilibrium conditions was considered. The considered input parameters were working frequency, maximum cross-sectional area, magnification coefficient, and the attached mass. At the end of the study, a new shape function of the horn’s cross section is obtained. The particularity of the new obtained shape is given by the nodal point position that is the same with the position of the maximum cross-sectional area. The obtained horn was analyzed from the modal point of view using theoretical and experimental methods. As theoretical methods, both the state-space method and the finite element method were used. An experimental setup for frequency response function determination was developed using a random input signal. The verification of the magnitude value was done considering a harmonic steady-state signal. The recorded values were compared with the predicted values. The numerical simulations and tests support the validity of the assumptions used in the horns optimization design.

scholarly journals Bimodal optimization with constraints: Critical value of the constraint and post-critical configurations

2011 ◽  
Vol 38 (2) ◽  
pp. 107-124
Author(s):  
Teodor Atanackovic ◽  
Alexander Seyraniany
Keyword(s):  
Total Energy ◽  
Critical Value ◽  
Optimal Shape ◽  
Cross Sectional Area ◽  
Point Of View ◽  
Sectional Area ◽  
Cross Sectional ◽  
Critical Configurations ◽  
Bimodal Optimization ◽  
Elastic Column

By using a method based on Pontryagin?s principle, formulated in [13], and [14] we study optimal shape of an elastic column with constraints on the minimal value of the cross-sectional area. We determine the critical value of the minimal cross-sectional area separating bi from unimodal optimization. Also we study the post-critical shape of optimally shaped rod and find the preferred configuration of the bifurcating solutions from the point of view of minimal total energy.

Optimization Design of an Efficient Evacuator for Gun Barrels

2021 ◽  
Author(s):  
Quanzhao Sun ◽  
Li Chen ◽  
Jie Zhang ◽  
Yanming Song ◽  
Guolai Yang ◽  
...  
Keyword(s):  
Optimization Design ◽  
Structural Parameters ◽  
Cross Sectional Area ◽  
Main Function ◽  
Sectional Area ◽  
Working Process ◽  
Cross Sectional ◽  
Mathematical Expressions ◽  
Reliability Indicator ◽  
The Cross

Abstract Evacuators are key components of gun barrels, and their main function is to drain the gunpowder gas remaining in the gun bore from the muzzle by ejection. To design an efficient evacuator for the gun barrels, an optimization model with the mathematical expressions describing the working process of the evacuator was established. The four structural parameters that affect the efficiency of the evacuator, including the volume of the gas storage cylinder chamber, the distance of the nozzle from the muzzle end face, the cross-sectional area of the nozzles and the cross-sectional area of the valves, were optimized. The effective working time and reliability indicator of the optimized evacuator were improved. This work describes a framework for improving the design of highly efficient evacuators on gun barrels.

Optimization design for shape-transition curved isolator with controllable cross-sectional area

2018 ◽  
Vol 152 ◽  
pp. 335-341 ◽  
Author(s):  
Zewei Meng ◽  
Xiaoqiang Fan ◽  
Yi Wang ◽  
Bing Xiong ◽  
Lei Lu
Keyword(s):  
Optimization Design ◽  
Cross Sectional Area ◽  
Shape Transition ◽  
Sectional Area ◽  
Cross Sectional

Optimization of High Concrete Retaining Wall Structure

2013 ◽  
Vol 357-360 ◽  
pp. 597-603
Author(s):  
Su Yang Gao ◽  
Yan Chen ◽  
Yao Feng Xie ◽  
Wen Dong Lei ◽  
Kai Yin
Keyword(s):  
Cross Section ◽  
Optimization Design ◽  
Retaining Wall ◽  
Cross Sectional Area ◽  
Wall Structure ◽  
Sectional Area ◽  
Cross Sectional ◽  
Structure Selection ◽  
Great Height ◽  
The Stability

The height of vertical pier retaining wall is relatively larger in regions with great height of water. As the retaining wall becomes higher, the cross-sectional area of ordinary gravity pier structure becomes larger and foundation strength needs to be larger, thus there are some restrictions for traditional structure form. This research focuses on new structure forms of high concrete retaining wall and its optimization design for piers in regions with great height of water. This study establishes a nonlinear constrained mathematical model of pier high retaining wall structures. The objective function is cross-sectional area of the pier retaining wall which is restricted by the stability, bearing capacity of foundation and strength of cross-section of retaining wall. This model is solved by fmincon function from Matlab and the results present an economically reasonable cross-section form. This new selection is greatly significant to improve the stability of high concrete retaining wall and reduce the project cost. The new structure is successfully used in a port of Huaihe River and it can be a solution to pier structure selection problem in regions with great height of water in the future.

Resilient Energy

1943 ◽  
Vol 16 (3) ◽  
pp. 591-608
Author(s):  
E. C. B. Bott
Keyword(s):  
Tensile Strength ◽  
Finite Differences ◽  
Practical Method ◽  
Cross Sectional Area ◽  
Point Of View ◽  
Sectional Area ◽  
Cross Sectional ◽  
Vulcanized Rubber ◽  
Reinforcing Agent ◽  
Strength Based

Abstract 1. The tensile strength of vulcanized rubber may be expressed in terms of its elongation by means of the calculus of finite differences. 2. This expression for tensile strength, based on the theoretical cross-sectional area, gives an expression for the tensile strength based on the original cross-sectional area when the former quantity is divided by the factor (E + 1), E being the elongation. 3. The expression for tensile strength based on the original cross-sectional area is integrated with respect to the elongation to give the resilient energy. 4. The trapezoidal rule has proved itself to be superior to the calculus of finite differences as a practical method of obtaining the resilient energy. 5. The total resilient energies are plotted on graphs against the percentage by volume of reinforcing agent or filler. Tangents drawn at any desired point corresponding to a certain percentage of filler give values for the partial resilient energies of base mix and of filler by the method of tangent intercepts. 6. The expressions for tensile strength are composed of one, two or three functions ; the number of functions is, in general, inversely proportional to the percentage of the filler in the vulcanizate. 7. The expressions for tensile strength and for resilient energies have no significance regarding the structure of vulcanized rubber; they have been evolved from the point of view of usefulness for evaluating compounds. 8. The values of the partial resilient energies of base mix and of filler obtained by the method of tangent intercepts have no physical meaning; they are a means of calculating the total resilient energy of a sample of vulcanized rubber.

Image Reconstruction of Blockage in the Continuous and Stepped Pipelines by Noninvasive Acoustic Method

2006 ◽  
Vol 321-323 ◽  
pp. 1640-1643
Author(s):  
Sung Soo Jung ◽  
S.I. Cho ◽  
Young Tae Kim ◽  
C.U. Cheong ◽  
Ho Chul Kim
Keyword(s):  
Image Reconstruction ◽  
Acoustic Waves ◽  
Acoustic Method ◽  
Cross Sectional Area ◽  
Sectional Area ◽  
Cross Sectional ◽  
New Approach ◽  
Resonance Frequencies ◽  
Transmission Pipeline

The image of a semi-circular blockage and location in the uniform and stepped pipe was reconstructed by measuring the eigen-frequency shift of the resonance and anti-resonance frequencies of multi-sine acoustic waves. In this study we have used different boundary conditions from previous works of Wu and Fricke [1] and De Salis and Oldham [2] to determine the blockage cross-sectional area and position. The results agreed with real fractional cross sectional area and position in the both continuous and stepped pipes. New approach showed a better quality of reconstructed image with small ripple number and the false dummy blockage signal was also reduced. The present method of blockage image reconstruction is a noninvasive nondestructive and can meet the integrity evaluation implementation for all types of transmission pipeline

Fascicular Topography of the Suprascapular Nerve in the C5 Root and Upper Trunk of the Brachial Plexus: A Microanatomic Study From a Nerve Surgeon's Perspective

2010 ◽  
Vol 67 (suppl_2) ◽  
pp. ons402-ons406 ◽  
Author(s):  
Mario G. Siqueira ◽  
Luciano H.L. Foroni ◽  
Roberto S. Martins ◽  
Gerson Chadi ◽  
Martijn J.A. Malessy
Keyword(s):  
Brachial Plexus ◽  
Sural Nerve ◽  
Specific Area ◽  
Suprascapular Nerve ◽  
Nerve Graft ◽  
Cross Sectional Area ◽  
Point Of View ◽  
Sectional Area ◽  
Cross Sectional ◽  
Sural Nerve Graft

ABSTRACT BACKGROUND: In patients with supraclavicular injuries of the brachial plexus, the suprascapular nerve (SSN) is frequently reconstructed with a sural nerve graft coapted to C5. As the C5 cross-sectional diameter exceeds the graft diameter, inadequate positioning of the graft is possible. OBJECTIVE: To identify a specific area within the C5 proximal stump that contains the SSN axons and to determine how this area could be localized by the nerve surgeon, we conducted a microanatomic study of the intraplexal topography of the SSN. METHODS: The right-sided C5 and C6 roots, the upper trunk with its divisions, and the SSN of 20 adult nonfixed cadavers were removed and fixed. The position and area occupied by the SSN fibers inside C5 were assessed and registered under magnification. RESULTS: The SSN was monofascicular in all specimens and derived its fibers mainly from C5. Small contributions from C6 were found in 12 specimens (60%). The mean transverse area of C5 occupied by SSN fibers was 28.23%. In 16 specimens (80%), the SSN fibers were localized in the ventral (mainly the rostroventral) quadrants of C5, a cross-sectional area between 9 o'clock and 3 o'clock from the surgeon's intraoperative perspective. CONCLUSION: In reconstruction of the SSN with a sural nerve graft, coaptation should be performed in the rostroventral quadrant of C5 cross-sectional area (between 9 and 12 o'clock from the nerve surgeon's point of view in a right-sided brachial plexus exploration). This will minimize axonal misrouting and may improve outcome.

Pelvic Canal Narrowing Caused by Triple Pelvic Osteotomy in the Dog

1994 ◽  
Vol 07 (03) ◽  
pp. 110-113 ◽  
Author(s):  
D. L. Holmberg ◽  
M. B. Hurtig ◽  
H. R. Sukhiani
Keyword(s):  
Postoperative Complications ◽  
Pelvic Osteotomy ◽  
Cross Sectional Area ◽  
Sectional Area ◽  
Cross Sectional ◽  
Canal Width ◽  
Operative Complications ◽  
Post Operative Complications

SummaryDuring a triple pelvic osteotomy, rotation of the free acetabular segment causes the pubic remnant on the acetabulum to rotate into the pelvic canal. The resulting narrowing may cause complications by impingement on the organs within the pelvic canal. Triple pelvic osteotomies were performed on ten cadaver pelves with pubic remnants equal to 0, 25, and 50% of the hemi-pubic length and angles of acetabular rotation of 20, 30, and 40 degrees. All combinations of pubic remnant lengths and angles of acetabular rotation caused a significant reduction in pelvic canal-width and cross-sectional area, when compared to the inact pelvis. Zero, 25, and 50% pubic remnants result in 15, 35, and 50% reductions in pelvic canal width respectively. Overrotation of the acetabulum should be avoided and the pubic remnant on the acetabular segment should be minimized to reduce postoperative complications due to pelvic canal narrowing.When performing triple pelvic osteotomies, the length of the pubic remnant on the acetabular segment and the angle of acetabular rotation both significantly narrow the pelvic canal. To reduce post-operative complications, due to narrowing of the pelvic canal, overrotation of the acetabulum should be avoided and the length of the pubic remnant should be minimized.

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