No description available.

No description available.

Cricket balls behave differently at various stages of the game depending upon how much wear and tear has taken place due to use. The playing performance of cricket balls depends largely on the surface texture. The ball is swung using the primary seam during the early stages of the game but later the surface roughness starts to affect the lateral movement. This work attempts to find a quantitative measure of the surface roughness of cricket balls and then uses it to discriminate between new and old balls. Area-scale fractal analysis is used to find the surface roughness in order discriminate between the balls. FTEST (a statistical tool) is also used to establish a discriminatory criterion between the old and new balls. Wind tunnel test results are presented to show the relationship between the surface roughness and drag. Finally a correlation between the roughness and drag of the cricket is shown.

The golf swing involves a complex sequence of body movements which adjust according to the demands of a given shot. The purpose of this study was to determine common characteristics and essential elements of the golf swing under various conditions. The swing patterns of thirteen elite professional golfers were analyzed using three-dimensional kinematics to determine the essential elements of optimal movement patterns for distance (DS; 1W), accuracy (AS; 8I), and intermediate (IS; 3I) shots, and a general model of golf swings. Two high-speed video cameras (250 frames per second) recorded frontal and sagittal views of the golf swings. Three-dimensional data were subsequently normalized across; (a) duration of each swing (N1) and (b) range of values and duration (N2). For these normalized data sets, F and t-tests were calculated for each kinematic variable for each point in normalized time across conditions. An ensembled plot was created for each data set and commonality and uniqueness analysis techniques were used to determine the essential elements of the golf swing. Despite similarities in the temporal characteristics of the golf swing across conditions, significant differences were observed in the top of swing positions (TOS). Lower body TOS preceded upper body TOS which preceded club TOS (p<.01). This sequencing suggested the existence of a "wind up motion" preceding downswing. The range of rotation for the hip, shoulder, and golf club segments were significantly different across conditions (DS>IS>AS, p<.05). Adjustment in the rotations depended upon the club selection and was proportional to the duration of the swing and the range of motion of the three segments. Commonality analysis results indicated that an optimal golf swing may be represented by a single model rather than a specific model for each golf club. The critical element during the swing was the constraint of the right knee and hip during the take away phase. During take away, the lower body rotated about the right leg while the upper body rotated about a point near mid-shoulders. For all clubs, the "wind up motion" initiated the downswing phase and was perhaps responsible for an initial delay of wrist uncocking during this phase. / Graduation date: 1995

Thesis (Ph. D.)--University of Texas at Austin, 2002. / Vita. Includes bibliographical references. Available also from UMI Company.

There is no abstract available for this thesis. / School of Physical Education

No description available.

Thesis (Ph. D.)--Victoria University (Melbourne, Vic.), 2006. / Includes bibliographical references.

Thesis (M.S.)--University of Wisconsin--Madison, 1969. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thesis (M.S.)--Ball State University, 2003. / Includes bibliographical references (leaves 54-57).