This study was designed to determine if college students perform differently when they are tested more frequently than less frequently. The purpose of this research study was: (a) to determine if there is a difference in achievement between students given weekly tests (experimental group) and students given monthly tests (control group), (b) to determine if there is a difference in knowledge retention between students given weekly tests and students given monthly tests, and (c) to determine if there is a difference in time spent studying between students given weekly tests and students given monthly tests. The research design used was a true experimental form of the posttest-only with control technique. The participants were 109 students taking Principles of Marketing at Concord College in Athens, West Virginia. Fifty were enrolled in the fall of 1996, and the study was replicated with 59 students who were enrolled in the spring of 1997. Half of each class (fall and spring) was randomly assigned to weekly testing and the other halves were assigned to monthly testing. The weekly and monthly groups were taught simultaneously by the researcher both semesters. To test for differences in achievement between the weekly group and the monthly group, the mean test scores were compared at 80-question intervals. To test for differences in knowledge retention between the weekly group and the monthly group, the mean final exam scores were compared. To test for differences in hours spent studying between the weekly group and the monthly group, the means from the self-reported study hours surveys were compared at 80-question intervals. Based on the results of analysis of covariance, the research showed a significant difference in achievement between the weekly and the monthly groups in favor of the weekly group ( p = .007). However, the difference between the weekly and monthly group final exam scores was not significant ( p = .553), and the difference between the weekly and monthly groups' self-reported study hours was also not significant ( p = .231). / Ph. D.

A crossover design study was conducted to determine if reducing pain, by using alternative sites off the finger tip, would increase testing frequency and improve clinical outcome as measured by glycosylated hemoglobin. Subjects with type I and type 2 diabetes tested with the FreeStyle alternative-site meter (group I) or tested with their original meter (group 2). After 3 months the subjects used the alternate meter. Testing frequency and blood glucose concentrations were recorded for the month before the study began and monthly thereafter. Glycosylated hemoglobin was tested initially, at the crossover point, and at study conclusion. Insulin users increased testing frequency from 2.4 to 3.0 tests per day. Testing frequency for non-insulin users remained the same at 1.5 tests per day. Testing frequency was essentially the same with the FreeStyle and the original meters. The average hemoglobin A1c was 7.4% (standard deviation 1.5%) initially, 7.3% (standard deviation 1.5%) at the crossover point, and 6.9% (standard deviation 1.1%) after 6 months. There was no significant difference in hemoglobin A1c measurements between meter types after 6 months. Thirteen months later a final hemoglobin A1c, testing frequency, and a questionnaire regarding meter preference and pain rating were obtained. Seventy-four percent of participants preferred the alternative-site meter, which was rated as significantly (p < .05) less painful. Testing frequency significantly improved (p = .001) while free strips were being provided. Testing frequency 13 months later was not significantly different from the baseline (p = .101). Hemoglobin A 1 c was significantly lower 6 months after the study began (p = .000) and 13 months later (p = .008) at baseline.

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This thesis present novel non-destructive laboratory test methods to characterize asphalt concrete. The testing is based on frequency response measurements of specimens where resonance frequencies play a key role to derive material properties such as the complex modulus and complex Poisson’s ratio. These material properties are directly related to pavement quality and used in thickness design of pavements. Since conventional cyclic loading is expensive, time consuming and complicated to perform, there has been a growing interest to apply resonance and ultrasonic testing to estimate the material properties of asphalt concrete. Most of these applications have been based on analytical approximations which are limited to characterizing the complex modulus at one frequency per temperature. This is a significant limitation due to the strong frequency dependency of asphalt concrete. In this thesis, numerical methods are applied to develop a methodology based on modal testing of laboratory samples to characterize material properties over a wide frequency and temperature range (i.e. a master curve). The resonance frequency measurements are performed by exciting the specimens using an impact hammer and through a non-contact approach using a speaker. An accelerometer is used to measure the resulting vibration of the specimen. The material properties can be derived from these measurements since resonance frequencies of a solid are a function of the stiffness, mass, dimensions and boundary conditions. The methodology based on modal testing to characterize the material properties has been developed through the work presented in paper I and II, compared to conventional cyclic loading in paper III and IV and used to observe deviations from isotropic linear viscoelastic behavior in paper V. In paper VI, detailed measurements of resonance frequencies have been performed to study the possibility to detect damage and potential healing of asphalt concrete.  The resonance testing are performed at low strain levels (~10^-7) which gives a direct link to surface wave testing of pavements in the field. This enables non-destructive quality control of pavements, since the field measurements are performed at approximately the same frequency range and strain level. / <p>QC 20141117</p>

Vibration generated from various sources (engine, road surface, tires, exhaust, etc.) should be considered in the design of a car body. These vibrations travel through transfer systems (drivetrain, suspension, body, etc.) to the steering wheel, seats and other areas where it is detected by the passengers of the vehicle. Transmission routes must be studied and efforts made to keep transfer systems from amplifying vibration and to absorb it instead. Since the superior vibration transfer system is the car body, finite element analysis and experimental vibration analysis are performed on car body-in-white. Body vibration analysis entails understanding and improving the body&rsquo / s dynamic characteristics that act as vibration transfer channels. In the previous study, a finite element model has been created for a car body-in-white available in Automotive Laboratory (Mechanical Engineering Department, Middle East Technical University, Ankara) and its natural frequencies and mode shapes have been determined using finite element analysis software. In this study, vibration tests have been performed on actual car body-in-white. Frequency response functions between 34 response locations and force application point have been measured. Using these frequency response functions, natural frequencies and mode shapes of the body-in-white have been determined. Finite element analysis and experimental results have been compared to evaluate the finite element model reliability.

Ultrasonic testing of concrete is often used for the assessment of its uniformity, strength, modulus of elasticity, durability and etc. therefore, the related parameters of testing such as the transducer frequency, the specimen geometry and etc. are well-known. On the other hand, most of the concrete properties are affected by the cement and the mechanical as well as some durability properties of cements are determined through cement mortars. Applications of ultrasound on determining the properties of cement mortars are quite limited. Therefore, the required specimen dimensions, transducer frequencies have not yet been established for cement mortars. In this study, ultrasonic pulse velocity (UPV) of mortars was determined with different transducers of different frequencies for different size ans shape of specimens. Within the scope of the experimental program, three different ultrasonic frequencies (54 kHz, 82 kHz, and 150 kHz) were utilized and the relation between ultrasonic testing frequency and specimen shape was experimentally investigated. It was concluded that the mechanical properties of mortar was adversely affected by the water-to-cement ratio. It was also observed that, when the length/wavelength ratio increases, the measured UPV with different transducer frequencies tends to converge to a single value. Finally, it was also concluded that an increase in moisture content of the mortar mixtures causes an increase in UPV and a decrease in compressive strength.

This study investigated the relationships between diverse variables and secondary school pupils' Mathematics achievement. It also dealt with the relative contribution of each variable to Mathematics achievement and the significance of differences in Mathematics achievements when pupils' gender and home background as well as teachers' experience, gender, education, in-service education, homework assignment and testing frequency are taken into account. A questionnaire was administered on 163 standard 8 pupils. I The most important findings of this study were: {1) There was a significant relationship between pupil variables and Mathematics achievement. (2) Pupil variables, particularly self-concept, contributed significantly towards the variance in Mathematics achievement. (3) Pupils who wrote tests often (more than once per term) achieved significantly less than students who wrote tests less often / Psychology of Education / M. Ed. (Psychology of Education)

This study investigated the relationships between diverse variables and secondary school pupils' Mathematics achievement. It also dealt with the relative contribution of each variable to Mathematics achievement and the significance of differences in Mathematics achievements when pupils' gender and home background as well as teachers' experience, gender, education, in-service education, homework assignment and testing frequency are taken into account. A questionnaire was administered on 163 standard 8 pupils. I The most important findings of this study were: {1) There was a significant relationship between pupil variables and Mathematics achievement. (2) Pupil variables, particularly self-concept, contributed significantly towards the variance in Mathematics achievement. (3) Pupils who wrote tests often (more than once per term) achieved significantly less than students who wrote tests less often / Psychology of Education / M. Ed. (Psychology of Education)