We consider unconstrained minimization of a finite sum of N continuously differentiable, not necessarily convex, cost functions. Several gradientlike (and more generally, line search) methods, where the full gradient (the sum of N component costs’ gradients) at each iteration k is replaced with an inexpensive approximation based on a sub-sample Nk of the component costs’ gradients, are availabl...

Given a line barrier and a set of mobile sensors distributed in the plane, the Minimizing Maximum Sensor Movement problem (MMSM) for line barrier coverage is to compute relocation positions for the sensors in the plane such that the barrier is entirely covered by the monitoring area of the sensors while the maximum relocation movement (distance) is minimized. Its weaker version, decision MMSM i...

This paper presents a new mathematical model for the problem of scheduling part families and jobs within each part family in a flow line manufacturing cell where the setup times for each family are sequence dependent and it is desired to minimize the maximum completion time of the last job on the last machine (makespan) while processing parts (jobs) in each family together. Gaining an optimal s...

We consider the problem of minimizing the number of ADMs in optical networks. All previous theoretical studies of this problem dealt with the off-line case, where all the lightpaths are given in advance. In a real-life situation, the requests (lightpaths) arrive at the network on-line, and we have to assign them wavelengths so as to minimize the switching cost. This study is thus of great impor...

A set of sensors establishes barrier coverage of a given line segment if every point of the segment is within the sensing range of a sensor. Given a line segment I, n mobile sensors in arbitrary initial positions on the line (not necessarily inside I) and the sensing ranges of the sensors, we are interested in finding final positions of sensors which establish a barrier coverage of I so that th...

Given a positive real value δ, a set P of points along a line and a distance function d, in the movement to independence problem, we wish to move the points to new positions on the line such that for every two points pi, pj ∈ P , we have d(pi, pj) ≥ δ while minimizing the sum of movements of all points. This measure of the cost for moving the points was previously unsolved in this setting. Howe...

A priciple task in parallel and distributed systems, such as networks of workstation or the Internet, is to reduce the communication load in the interconnection network, for the bandwidth of the connection network is usually the major bottleneck for the performance of distributed applications. This is due to the fact that it is often more expensive or more difficult to increase the bandwidth of...

Automatic ring protection provides simple and rapid fault protection and restoration in telecommunication networks. To implement the automatic ring protection in general wavelengthdivision multiplexing (WDM) optical networks, the lightpaths are partitioned into groups each of which can be carried in a simple cycle of the underlying network. As the electronic line terminals are the dominant cost...