Youth and varsity football helmets are currently designed similarly and tested to the same impact standards from the National Operating Committee on Standards for Athletic Equipment (NOCSAE). Youth players have differences in anthropometry, physiology, impact exposure, and potentially injury tolerance that should be considered in future youth-specific helmets and standards. This thesis begins by investigating the current standards and relating them to on-field data. The standard drop tests represented the most severe on-field impacts, and the performance of the youth and varsity helmet did not differ. There likely is not a need for a youth-specific standard as the current standard has essentially eliminated the catastrophic head injuries it tests for. As more is known about concussion, standards specific to the youth population can be developed. The second portion of this thesis compares the impact performance between 8 matched youth and varsity helmet models, using linear acceleration, rotational acceleration, and concussion correlate. It was found that helmet performance did not differ between the youth and varsity helmets, likely attributed to testing to the same standard. The final portion of this feature is aimed at advancing STAR for youth and varsity football helmets by including linear and rotational head kinematics. For varsity helmets, an adult surrogate is used for impact tests which are weighted based on on-field data collected from collegiate football players. For youth helmets, a youth surrogate is used and tests are weighted based on data collected from youth players. / Master of Science / The research presented in this thesis is intended to provide a reference point towards youth-specific football helmets and test standards. Currently, youth football helmets are designed similarly to varsity football helmets and are tested to the same standard. It is known that differences exist between youth and adult players in terms of the impacts they experience, the proportions of their body, and the maturity of the nervous system. However, it remains unknown as to how these differences should be expressed in youth-specific helmet design and impact standards. This thesis investigates the current test standard and relates it to population-specific on-field data. This analysis of both a youth and varsity helmet, suggest that there is no current benefit for a youth-specific standard until differences in concussion tolerance are better understood. This thesis goes on to compare the relative impact performance between multiple matched youth and varsity helmets, using a more realistic test setup than the current impact standards. Through this investigation it was found that there were no differences in performance between the youth and varsity helmets tested. This thesis then concludes by advancing STAR for youth and varsity football helmets, using a separate protocol specific to each population. Each test protocol is able to identify helmets that most effectively reduce the severity of head impacts in football.

Four full-size statically indeterminate reinforced concrete frames with two symmetrical bays were tested to obtain sufficient data to evaluate the adequacy of the current ACI-ASCE Committee 352 design recommendations, as well as to determine whether a relaxation of some of the limits in these guidelines can be justified. Each specimen contained three 8.5-foot-long columns, connected at mid-height by two 9-foot-long beams. Initially, a constant axial load was applied to each column. The specimens were then subjected to a displacement-controlled loading schedule to simulate the type of displacements a frame may experience during a severe earthquake. In designing the specimens, the latest recommendations of the ACI-ASCE Committee 352 and the ACI building code ACI 318-83 were satisfied except for the following modifications: (1) the flexural strength ratio (M(R)) in the second specimen was reduced from 1.4 to 1.2, (2) the shear-stress factors (γ) in the joints of the third specimen were increased from 12 and 15 to 15 and 20 for the exterior and interior joints respectively, and (3) the number of the transverse reinforcements inside the right exterior joint in the fourth specimen was reduced from 4 to 2 sets of hoops. The conclusion inferred from the results indicate that for drift levels within the elastic range, the elongations and the rotations of the beam regions near the faces of the columns, in addition to the joint shear strains, were not affected by the design values for the primary variables in the last three specimens. For larger excursions into the inelastic range, the relaxation of the current Committee 352 design recommendations in the last three specimens not only showed a significant effect in reducing the elongations and the rotations of the beams, or in increasing the joint shear strains but led to lower energy dissipation of the specimens. Consequently, the current design guidelines by the ACI-ASCE Committee 352 yield statically indeterminate frames which exhibit sufficient ductility.

Since the late 1800s, testing has been a part of education. Supporters claim testing encourages objectivity in assessments of learning. Critics argue testing creates bias, restricted teaching methodology, and restricted curriculum. The No Child Left Behind Act of 2001 requires school accountability that has increased the push for standardized testing. High school students present a unique challenge for administrators on the low-risk California Standards Tests (CSTs). The CSTs in mathematics are complex in reference to student composition, range of courses tested, and sequence of previous math courses taken by the student. This complex nature of the CSTs in mathematics makes test preparation decisions difficult for the site administrator. Schools have developed test preparation practices in the hopes of improving student performance on these standardized tests. Some of these practices require a great deal of time, energy, and money to create and execute. The administrator must use these precious resources judiciously. Therefore, there is a need for further investigation of the criteria used by site administrators for selection of test preparation practices for CSTs in mathematics. Using qualitative analysis, this study researched the criteria used by the high school site administrators to govern their decision of which test preparation practices for CSTs in mathematics to establish at their school. This study included 18 administrators at 15 schools in the southern San Joaquin Valley in California that met their Academic Performance Index growth targets for 2006.