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The author reflects on the approaches to problems of route planning for movements of robots. He explores the two approaches for solving the problem such as the first which uses recognized global environment that limits the information and characteristic of a robot and the second which uses local sensor information and considers the characteristics of the robot. He discusses the project at the Universidad Carlos III de Madrid Spain, which use the Voroni diagram and the fast marching method.

Purpose: The objective of this study is to determine the effects of a caffeine-containing energy drink on female volleyball players' performance. Methods: Thirteen elite female volleyball players ingested 3 mg·kg-1 of caffeine with an energy drink or the same drink without caffeine (placebo drink) in a double-blind and randomized study. Then, participants performed the following: standing spike, jumping spike, spike jump, blocking jump, squat jump, counter movement jump, manual dynamometry, and the agility t-test. A simulated volleyball game was played, videotaped, and notated afterward. Results: In comparison to the placebo drink, the ingestion of the caffeinated energy drink increased the ball velocity in the standing spike (19.2 ± 2.1 vs 19.7 ± 1.9 m.s-1, P = 0.023) and in the jumping spike (17.9 ± 2.2 vs 18.8 ± 2.2 m.s-1, P = 0.038) and the jump height in the squat jump (28.1 ± 3.2 vs 29.4 ± 3.6 cm, P = 0.028), countermovement jump (32.0 ± 4.6 vs 33.1 ± 4.5 cm, P = 0.018), spike jump (43.3 ± 4.7 vs 44.4 ± 5.0 cm, P = 0.025), and block jump (35.2 ± 5.1 vs 36.1 ± 5.1 cm, P = 0.044). Furthermore, the caffeinated energy drink decreased the time needed to complete the agility t-test (11.1 ± 0.5 vs 10.9 ± 0.3 s, P = 0.036). During the game, the volleyball actions categorized as successful were more frequent with the caffeinated energy drink (34% ± 9% vs 45% ± 9%, P < 0.001), whereas imprecise actions decreased (28% ± 7% vs 14% ± 9%, P < 0.001) when compared with the placebo drink. Conclusion: Commercially available energy drinks can significantly improve physical performance in female volleyball players. Increased physical performance led to improved accuracy during an actual volleyball match. [ABSTRACT FROM AUTHOR]