The purpose of this study was to test the effect of a jump-training program on landing mechanics and lower extremity strength in female athletes involved in jumping sports. These parameters were compared before and after training with those of male athletes. The program was designed to decrease landing forces by teaching neuromuscular control of the lower limb during landing and to increase vertical jump height. After training, peak landing forces from a volleyball block jump decreased 22%, and knee adduction and abduction moments (medially and laterally directed torques) decreased approximately 50%. Multiple regression analysis revealed that these moments were significant predictors of peak landing forces. Female athletes demonstrated lower landing forces than male athletes and lower adduction and abduction moments after training. External knee extension moments (hamstring muscle-dominant) of male athletes were threefold higher than those of female athletes. Hamstring-to-quadriceps muscle peak torque ratios increased 26% on the nondominant side and 13% on the dominant side, correcting side-to-side imbalances. Hamstring muscle power increased 44% with training on the dominant side and 21% on the nondominant. Peak torque ratios of male athletes were significantly greater than those of untrained female athletes, but similar to those of trained females. Mean vertical jump height increased approximately 10%. This training may have a significant effect on knee stabilization and prevention of serious knee injury among female athletes.

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For several decades at the Department of Energy's Savannah River Site, large underground storage tanks have been used to contain highly radioactive waste. This waste must now be transported out of the tanks to be processed into a more suitable long-term storage medium. In addition, the emptied tanks must be cleaned in adherence to both state and federal requirements before being permanently closed. Unfortunately, transfer of the waste by pump leaves behind several types of waste forms away from pump suction: highly alkaline and radioactive sludge, rock-like solid masses called clinkers, or large, solidified salt formations known as tank heels. These waste forms must be dissolved and moved on the tank bottom to pump locations prior to being removed from the tank.A low cost crawler is being developed to carry a range of tools to dissolve or breakup the residual heel and clinkers left in these large storage tanks and move the waste so that it can be easily pumped out of the waste tanks. The remotely operated tool platform being developed will carry a water cannon and other water conveyance devices and will be able to access the tanks through available small access ports. This paper will discuss the cleaning challenge, possible solutions and their evaluation and selection, design, development, and mockup testing results of a low cost, mobile, teleoperated, tool platform for breaking up large waste deposits remaining in underground waste storage tanks.