The built up layer thickness in secondary deformation zone is one of the important parameters in metal cutting process. The built up layer (BUL) is formed in second deformation zone near the tool-chip interface in the back of the chip. This parameter influences the tool life and machined surface quality. This BUL should not be confused with the built up edge (BUE). The deformation of the BUL in...

A new algorithm for solving convex stochastic optimization problems with expectation functions in both the objective and constraints is presented. The algorithm combines a stochastic hybrid procedure, which was originally designed to solve problems with expectation only in the objective, with dual stochastic gradient ascent. More specifically, the algorithm generates primal iterates by minimizi...

Optimization of on-demand transportation systems and ride-sharing services involves solving a class of complex vehicle routing problems with pickup and delivery with time windows (VRPPDTW). This paper first proposes a new time-discretized multi-commodity network flow model for the VRPPDTW based on the integration of vehicles’ carrying states within space–time transportation networks, so as to a...

This short article analyzes an interesting property of the Bregman iterative procedure, which is equivalent to the augmented Lagrangian method, for minimizing a convex piece-wise linear function J(x) subject to linear constraints Ax = b. The procedure obtains its solution by solving a sequence of unconstrained subproblems of minimizing J(x)+ 12‖Ax−b ‖2, where b k is iteratively updated. In prac...

A broad class of engineering problems including penetration, tmpact and large rotations of solid bodies causes severe numerical problems. For these problems, the constitutive equations are history dependent so material points must be followed; this is difficult to implement in a Eulerian scheme. On the other hand, purely Lagrangian methods typically result in severe mesh distortion and the cons...

In this paper, an immersed boundary method is proposed for the simulation of two-dimensional fluid interfaces with insoluble surfactant. The governing equations are written in a usual immersed boundary formulation where a mixture of Eulerian flow and Lagrangian interfacial variables are used and the linkage between these two set of variables is provided by the Dirac delta function. The immersed...

In the early stage of floorplan design, many modules have large flexibilities in shape (soft modules). Handling soft modules in general nonslicing floorplan is a complicated problem. Many previous works have attempted to tackle this problem using heuristics or numerical methods, but none of them can solve it optimally and efficiently. In this paper, we show how this problem can be solved optima...

This paper appraises two major chip formation techniques in finite element (FE) simulation of machining. The first one considers chip formation as a wedge indentation process, while the second one considers chip separation due to ductile fracture. The first technique has been implemented in an Arbitrary Lagrangian-Eulerian (ALE) simulation of machining and the chip formation is assumed to be du...