This paper presents a new algorithm for solving the generalized watchman problem. It is the problem of mobile robot operators that must find the shortest route for the robot to see the whole area with many obstructions. The algorithm adapts the well-known ant algorithm to the new problem. An experiment where the algorithm is applied to an area containing more than 10 obstructions is described. ...

It has been suggested that codimension-two braneworlds might naturally explain the vanishing of the 4D effective cosmological constant, due to the automatic relation between the deficit angle and the brane tension. To investigate whether this cancellation happens dynamically, and within the context of a realistic cosmology, we study a codimension-two braneworld with spherical extra dimensions c...

In the contract-theoretic literature, there is a vital debate about whether contracts can mitigate the hold-up problem, in particular when renegotiation cannot be prevented. Ultimately, the question has to be answered empirically. As a first step, we have conducted a laboratory experiment with 1084 participants. We consider investments that directly benefit the non-investing party. While accord...

© American Political Science Association, 2015 PS • January 2015 75 ........................................................................................................................................................................................................................................................................................................ ...................................

A basic problem in contracting is holdup: after one party has made relationship-specific investments, the other party refuses to perform unless the first one offers better terms than the original contract. Such renegotiation deters relationship-specific investments and reduces the value of trade via contract, which can either result in no trade or more trade within firms. A classic example is t...

The purpose of this work was to compare two forms of genetic algorithm (complete and incomplete graph version) which solves Orienteering Problem (OP). While in most papers concerning OP graph is complete and satisfies triangle inequality, in our versions such assumptions may not be satisfied. It could be more practical as transport networks are graphs which do not have to satisfy those conditio...

the pupose of this paper is modeling of partial digest problem (pdp) as a mathematical programming problem. in this paper we present a new viewpoint of pdp. we formulate the pdp as a continuous optimization problem and develope a method to solve this problem. finally we constract a linear programming model for the problem with an additional constraint. this later model can be solved by the simp...

this paper presents a new nonlinear mathematical model to solve a cell formation problem which assumes that processing time and inter-arrival time of parts are random variables. in this research, cells are defined as a queue system which will be optimized via queuing theory. in this queue system, each machine is assumed as a server and each part as a customer. the grouping of machines and parts...