Power-constrained block-test list scheduling

A list scheduling approach is proposed in this paper to overcome the problem of unequal-length block-test scheduling under power dissipation constraints. An extended tree growing technique is also used in combination with the list scheduling algorithm in order to improve the test concurrency, having assigned power dissipation limits. Moreover, the algorithm features a power dissipation balancing provision. Test scheduling examples are discussed, highlighting further research steps towards an efficient system-level test scheduling algorith

A comparison of classical scheduling approaches in power-constrained block-test scheduling

Classical scheduling approaches are applied here to overcome the problem of unequal-length block-test scheduling under power dissipation constraints. List scheduling-like approaches are proposed first as greedy algorithms to tackle the fore mentioned problem. Then, distribution-graph based approaches are described in order to achieve balanced test concurrency and test power dissipation. An extended tree growing technique is also used in combination with these classical approaches in order to improve the test concurrency having assigned power dissipation limits. A comparison between the results of the test scheduling experiments highlights the advantages and disadvantages of applying different classical scheduling algorithms to the power-constrained test scheduling proble

Distribution-graph based approach and extended tree growing technique in power-constrained block-test scheduling

A distribution-graph based scheduling algorithm is proposed together with an extended tree growing technique to deal with the problem of unequal-length block-test scheduling under power dissipation constraints. The extended tree growing technique is used in combination with the classical scheduling approach in order to improve the test concurrency having assigned power dissipation limits. Its goal is to achieve a balanced test power dissipation by employing a least mean square error function. The least mean square error function is a distribution-graph based global priority function. Test scheduling examples and experiments highlight in the end the efficiency of this approach towards a system-level test scheduling algorithm

A combined tree growing technique for block-test scheduling under power constraints

A tree growing technique is used here together with classical scheduling algorithms in order to improve the test concurrency having assigned power dissipation limits. First of all, the problem of unequal-length block-test scheduling under power dissipation constraints is modeled as a tree growing problem. Then a combination of list and force-directed scheduling algorithms is adapted to tackle it. The goal of this approach is to achieve rapidly a test scheduling solution with a near-optimal test application time. This is initially achieved with the list approach. Then the power dissipation distribution of this solution is balanced by using a force-directed global priority function. The force-directed priority function is a distribution-graph based global priority function. A constant additive model is employed for power dissipation analysis and estimation. Based on test scheduling examples, the efficiency of this approach is discussed as compared to the other approaches

Thermal-Safe Test Scheduling for Core-Based System-on-a-Chip Integrated Circuits

Overheating has been acknowledged as a major problem during the testing of complex system-on-chip (SOC) integrated circuits. Several power-constrained test scheduling solutions have been recently proposed to tackle this problem during system integration. However, we show that these approaches cannot guarantee hot-spot-free test schedules because they do not take into account the non-uniform distribution of heat dissipation across the die and the physical adjacency of simultaneously active cores. This paper proposes a new test scheduling approach that is able to produce short test schedules and guarantee thermal-safety at the same time. Two thermal-safe test scheduling algorithms are proposed. The first algorithm computes an exact (shortest) test schedule that is guaranteed to satisfy a given maximum temperature constraint. The second algorithm is a heuristic intended for complex systems with a large number of embedded cores, for which the exact thermal-safe test scheduling algorithm may not be feasible. Based on a low-complexity test session thermal cost model, this algorithm produces near-optimal length test schedules with significantly less computational effort compared to the optimal algorithm

Optimal security-constrained power scheduling by Benders decomposition

This paper presents a Benders decomposition approach to determine the optimal day-ahead power scheduling in a pool-organized power system, taking into account dispatch, network and security constraints. The study model considers the daily market and the technical constraints resolution as two different and consecutive processes. The daily market is solved in a first stage subject to economical criteria exclusively and then, the constraints solution algorithm is applied to this initial dispatch through the redispatching method. The Benders partitioning algorithm is applied to this constraints solution process to obtain an optimal secure power scheduling. The constraints solution includes a full AC network and security model to incorporate voltages magnitudes as they are a critical factor in some real power systems. The algorithm determines the active power committed to each generator so as to minimize the energy redispatch cost subject to dispatch, network and security constraints. The solution also provides the reactive power output of the generators, the value of the transformers taps and the committed voltage control devices. The model has been tested in the IEEE 24-bus Reliability Test System and in an adapted IEEE 118-bus Test System. It is programmed in GAMS mathematical modeling language. Some relevant results are reported.Publicad