Examination timetabling problem (ETP) is one of the most important issues in universities. An improper timetable may result in students' dissatisfaction as it may not let them study enough between two sequential exams. In addition, the many exams to be scheduled, the large number of students who have taken different courses, the limited number of rooms, and some constraints su...

We present in this paper new results on the duality gap between the binary quadratic optimization problem and its Lagrangian dual or semidefinite programming relaxation. We first derive a necessary and sufficient condition for the zero duality gap and discuss its relationship with the polynomial solvability of the primal problem. We then characterize the zeroness of the duality gap by the dista...

We describe an effective method for doing binary-encoded modeling, in the context of 0/1 linear programming, when the number of feasible configurations is not a power of two. Our motivation comes from modeling all-different restrictions.

We study the upper bounds for $A(n,d)$, maximum size of codewords with length $n$ and Hamming distance at least $d$. Schrijver studied Terwilliger algebra scheme proposed a semidefinite program to bound $A(n, d)$. derive more sophisticated matrix inequalities based on split improve Schrijver's programming In particular, we $A(18,4)$ $6551$.

Although there are a lot of optimized concurrent algorithms for lists, queues, stacks, hash tables and other common data structures, there are much fewer optimized concurrent Binary Search Trees implementations. This paper compares several concurrent implementations of Binary Search Tree. The implementations are also compared to a concurrent skip list, which is the general way to implement a co...

In this paper, genetic algorithms for the un-constrained binary quadratic programming problem (BQP) are presented. It is shown that for small problems a simple genetic algorithm with uniform crossover is suucient to nd optimum or best-known solutions in short time, while for problems with a high number of variables (n 200) it is essential to incorporate local search to arrive at high-quality so...