Impact of Standing Desk Intervention on Sedentary Behavior of 4th Grade Students

Abstract The object of this study was to compare the differences in sedentary behavior of fourth grade students at standing desks to those at traditional desks. The hypothesis of implementing standing desks within the classroom was to decrease the sedentary behavior of the students and the null hypothesis was that the results would show no statistically significant difference. Research took place at a small private elementary in the Midwest. Data was collected on thirteen 4th grade students using accelerometers. The thirteen students were split into groups of four, and the intervention was completed with each individual group for a quarter of the school year. During the assessment, students wore accelerometers for a school week at the beginning of intervention and for another week at the end of the intervention. Data was collected through accelerometers on the ActivPal software. Analysis of the data was done using two tailed independent t-tests to compare all of the data from students at standing desk to students at the traditional desks. The behaviors of total number of sedentary bouts, average sedentary breaks, total sedentary time, and average daily sedentary time were all behaviors found significantly different. The statistical hypothesis is accepted, given that implementing standing desks affected the sedentary behavior of the students

Prediction of aeroelastic response of a model X-wing rotor

The rotorcraft dynamics analysis was used to predict the aeroelastic responses of a representative X-wing model with a 10 ft diameter rotor. The aeroelastic methodology used and the tests and assumptions involved are reviewed. Results are reported on the findings concerning control power and higher harmonic control in hover, transition flight, vibratory loads at forward speed, and responses in conversion. It is concluded that the analysis can give satisfactory predictions of X-wing behavior