Biogeography-based optimization (BBO) has recently become popular in unmanned aerial vehicle (UAV) path planning. Similar to other evolutionary algorithms, the performance of BBO is affected when the parameter setting is not finely tuned. Therefore, the BBO parameters are optimized in this research particularly for application in UAV path planning. Each combination setting of parameters is simu...

A shortest path search method based on ant colony algorithm is proposed. The method contracts the search space appropriately, obtaining, in a short time, a path that is as close as possible to the path obtained by the Dijkstra method (the optimum path). To improve the performance, we modify the pheromone update rule and introduce a learning strategy into the ant colony algorithm. The method obt...

This paper describes a novel optimum path planning strategy for long duration AUV operations in environments with time-varying ocean currents. These currents can exceed the maximum achievable speed of the AUV, as well as temporally expose obstacles. In contrast to most other path planning strategies, paths have to be defined in time as well as space. The solution described here exploits ocean c...

A secondary path modeling technique for active noise control systems is developed for both on-line and off-line modeling with faster convergence and higher modeling accuracy. The optimum delay for the adaptive prediction error filter to reduce the interference in system modeling is equal to the length of the impulse response of the secondary path being modeled.

We present an approximation algorithm for the shortest descending path problem. Given a source s and a destination t on a terrain, a shortest descending path from s to t is a path of minimum Euclidean length on the terrain subject to the constraint that the height decreases monotonically as we traverse that path from s to t. Given any ε ∈ (0, 1), our algorithm returns in O(n log(n/ε)) time a de...

Increasing socio-economic status is associated with increasing levels of subjective well-being. Subjective well-being is in turn associated with physical and mental health. In this study, socio-economic gradients in subjective well-being are investigated in a large cross-section of the British population. Higher socioeconomic groups are more satisfied with life and have fewer psychosomatic symp...