Filters








438,993 Hits in 3.7 sec

Segmentation of Cutting Path Based on Feed Rate Interval

XIEGUO XIE, GUANGRONG YAN, XIANGYU XU, ZAIJUN WANG
2017 DEStech Transactions on Engineering and Technology Research  
For given CNC machining codes, the sampling point sequence of cutting path is processed and optimized by using the greedy method or the dynamic programming method in the case of basically satisfying the  ...  This paper provides an optimization method of cutting path segmentation.  ...  ACKNOWLEDGEMENTS The research work was financially supported by the Project named Technology and Equipment of NC Machining Unit for Aircraft Complex Structure (No. 2013 ZX04001031).  ... 
doi:10.12783/dtetr/icvmee2017/14654 fatcat:wivhw7lyeveulh2qkgrfxje4vu

A Tighter Piecewise Linear Approximation of Quadratic Cost Curves for Unit Commitment Problems

Lei Wu
2011 IEEE Transactions on Power Systems  
This letter discusses a rigorous segment partition method for obtaining a set of optimal segment points by minimizing the difference between chord and arc lengths, in order to derive a tighter piecewise  ...  In order to facilitate the UC optimization process with efficient mixed-integer linear programing (MILP) solvers, QCCs are piecewise linearized for converting the original mixed-integer quadratic programming  ...  TABLE III SEGMENT III POINTS COMPARISON TABLE IV SOLUTIONS IV USING THE PROPOSED SEGMENT PARTITION METHOD segment points that are different from the points obtained from the equipartition method are  ... 
doi:10.1109/tpwrs.2011.2148370 fatcat:jayza5fchjgs5bjzkoa6epuila

Page 34 of Geographical Analysis Vol. 23, Issue 1 [page]

1991 Geographical Analysis  
Moreover, the vast majority of computational time for the optimal routine was consumed in the preprocessing stage, not in the dynamic programming stage (see Table 5).  ...  containing the ending points of all allowable segments that begin at point j.  ... 

On Optimal Non-Overlapping Segmentation and Solutions of Three-Dimensional Linear Programming Problems through the Super Convergent Line Series

Thomas Ugbe, Polycarp Chigbu
2017 American Journal of Operations Research  
The cuboidal response surface was segmented up to four segments, and explored. It was verified that the number of segments, S, for which optimal solutions are obtained is two (S = 2).  ...  The solutions of Linear Programming Problems by the segmentation of the cuboidal response surface through the Super Convergent Line Series methodologies were obtained.  ...  Programming Problems, for non-over-lapping segmentation of the response surface.  ... 
doi:10.4236/ajor.2017.73015 fatcat:ty6ptvfwq5bcjp52pxmidhqicm

Optimization Models of Tool Path Problem for CNC Sheet Metal Cutting Machines

Alexander A. Petunin, Chrysostomos Stylios
2016 IFAC-PapersOnLine  
Users of CAD/CAM systems develop numerical control programs for the cutting equipment after nesting of parts onto the sheet. The control programs contain information about tool path.  ...  Users of CAD/CAM systems develop numerical control programs for the cutting equipment after nesting of parts onto the sheet. The control programs contain information about tool path.  ...  DISCRETE MODELS OF OPTIMIZATION PROBLEMS FOR THE TOOL PATH ROUTING As the main optimization problem we consider Segment Continuous Cutting Problem (SCCP) for objective functions (2)-(5) (see Petunin (  ... 
doi:10.1016/j.ifacol.2016.07.544 fatcat:rbeti366vbhh3pnhwde3eeyigu

Models and Algorithms for Optimal Piecewise-Linear Function Approximation

Eduardo Camponogara, Luiz Fernando Nazari
2015 Mathematical Problems in Engineering  
Piecewise-linear functions can approximate nonlinear and unknown functions for which only sample points are available.  ...  The models include piecewise-linear functions with a fixed and maximum number of linear segments, lower and upper envelopes, strategies to ensure continuity, and a generalization of these models for stochastic  ...  Problem le , is a nonlinear program for which algorithms reach a locally optimal solution, such as sequential quadratic programming (SQP).  ... 
doi:10.1155/2015/876862 fatcat:mg6yxlaapbcdrlm74ycgnzxuqi

On the new Algorithm for Solving Continuous Cutting Problem

A.A. Petunin, E.G. Polishchuk, S.S. Ukolov
2019 IFAC-PapersOnLine  
into account, that is crucial for generating correct CNC programs due to technological features of modern CNC cutting equipment.  ...  AbstractThe problem of tool path optimization for CNC (Computer Numerical Control) thermal cutting machines as well as its classification are considered.  ...  Example of cutting tool path for two parts with three pierce points NC program usually starts with an air move from some starting point.  ... 
doi:10.1016/j.ifacol.2019.11.552 fatcat:ppe7vxj3svbavg5x7owcmnbasa

Page 351 of Journal of Spacecraft and Rockets Vol. 5, Issue 3 [page]

1968 Journal of Spacecraft and Rockets  
The problem becomes one of parame- ter optimization.*~* On the other hand, if a gradient optimization program is available, it would seem wise to take advantage of it, for the programming and checking  ...  A change in the @ at a break point affects only the two linear segments sur- rounding it.  ... 

Discrete Pseudocontrol Sets for Optimal Control Problems

Yuri Ulybyshev
2010 Journal of Guidance Control and Dynamics  
Linear programming for linear optimal control problems is proposed by Dantzig [5].  ...  We consider an ith segment independent of all the other segments. Suppose that there is an optimal value U;opp € Q = [Umins Umax] for the segment.  ... 
doi:10.2514/1.47315 fatcat:6yk4z4odjrc2bdq6bzzb5n6sle

Spacecraft Trajectory Optimization Based on Discrete Sets of Pseudoimpulses

Yuri Ulybyshev
2009 Journal of Guidance Control and Dynamics  
Suppose that there is an optimal impulse AV;,,, for the ith segment.  ...  Spacecraft Trajectory Optimization in Linear Programming Form A. Spacecraft Motion Model We consider a point-mass spacecraft with a limited thrust.  ... 
doi:10.2514/1.41201 fatcat:f3ac2bqwpvfnhcsb2l54xfsyxy

The point-to-point connection problem — analysis and algorithms

Madan Natu, Fang Shu-Cherng
1997 Discrete Applied Mathematics  
We also provide a dynamic programming algorithm with complexity C' (n' ') for the case with three source-destination pairs.  ...  The point-to-point connection problem is to find a subset of arcs with minimal total cost connecting a fixed number of source-destination pairs.  ...  Mark Hartman of the University of North Carolina, Chapel Hill, for pointing out Ref. [l] to us, and for suggesting an efficient  ... 
doi:10.1016/s0166-218x(97)00010-3 fatcat:use25bectzd2pcj2rbbomz36la

Noninferior Bandwidth Line Simplification: Algorithm and Structural Analysis

Robert G. Cromley, Gerard M. Campbell
2010 Geographical Analysis  
for storing the optimal length of the path to each point within M of the current point j.  ...  Moreover, the vast majority of computational time for the optimal routine was consumed in the preprocessing stage, not in the dynamic programming stage (see Table 5).  ... 
doi:10.1111/j.1538-4632.1991.tb00219.x fatcat:3twi3rueczbwnacve6dgjma2de

General Model of Tool Path Problem for the CNC Sheet Cutting Machines

Alexander Petunin
2019 IFAC-PapersOnLine  
General model of tool path problem for laser/plasma/gas/water-jet machines is offered. Model uses the term "the basic cutting segment" proposed by author.  ...  General model of tool path problem for laser/plasma/gas/water-jet machines is offered. Model uses the term "the basic cutting segment" proposed by author.  ...  AKNOWLEDGMENTS The work was supported by the Russian Foundation for Basic Research (grant № 17-08-01385) and by Act 211 Government of the Russian Federation, contract №02.A03.21.0006.  ... 
doi:10.1016/j.ifacol.2019.11.609 fatcat:ypsiw5ft2jbadg7rcybwlqu32i

Separation of Left and Right Lungs Using 3-Dimensional Information of Sequential Computed Tomography Images and a Guided Dynamic Programming Algorithm

Sang Cheol Park, Joseph Ken Leader, Jun Tan, Guee Sang Lee, Soo Hyung Kim, In Seop Na, Bin Zheng
2011 Journal of computer assisted tomography  
point and end point with especially severe and multiple connections.  ...  traditional dynamic programming and avoided the permeation of the separation boundary into normal lung tissue.  ...  For this purpose, the scheme saves the optimal path and the middle point of the optimal path. The middle point was named "cut point".  ... 
doi:10.1097/rct.0b013e31820e4389 pmid:21412104 pmcid:PMC3061932 fatcat:i3thlceujjczhjfl3qokgkqkwq

A log-linear time algorithm for constrained changepoint detection [article]

Toby Dylan Hocking, Guillem Rigaill, Paul Fearnhead, Guillaume Bourque
2017 arXiv   pre-print
One example is ChIP-seq data, for which adding an up-down constraint improves peak detection accuracy, but makes the optimization problem more complicated.  ...  For some applications, it is natural to impose constraints on the directions of changes.  ...  Equivalent optimization space The reduced isotonic regression problem (3) has n segment mean variables m t , one for each data point t.  ... 
arXiv:1703.03352v1 fatcat:o5mfw4bbgrdetpcqjb3knr6ip4
« Previous Showing results 1 — 15 out of 438,993 results