Although graduation rates are increasing in Georgia and in the United States, high school dropouts remain an issue of significant concern. Much of the focus of research in this area has been on describing the characteristics of dropouts rather than on developing effective interventions. Moreover, emerging research shows that potential dropouts can be identified with confidence as early as the sixth grade. High school is the time in which dropouts are typically identified and interventions begun, but the seeds of dropping out are often planted well before ninth grade. This study is about school administrators’ perceptions of drop-out factors in three urban high schools. The research design lies within the qualitative spectrum. Data were gathered from semi-structured, open-ended interviews conducted with selected participants. Results showed there were no significant differences in the perception of high school principals as to the importance of specific intervention factors affecting student dropout rates. The participants agreed that instructional coaches, after-school and Saturday school programs and the use of data to target content needs of specific students were the common themes of support to students at-risk of not completing high school requirements.

Made available in DSpace on 2014-10-09T12:38:23Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:05:53Z (GMT). No. of bitstreams: 1 05724.pdf: 6566331 bytes, checksum: 217859b9c420011d3a1761390d6692db (MD5) / Tese (Doutoramento) / IPEN/T / Escola Politecnica, Universidade de Sao Paulo - POLI/USP

Made available in DSpace on 2014-10-09T12:38:23Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:05:53Z (GMT). No. of bitstreams: 1 05724.pdf: 6566331 bytes, checksum: 217859b9c420011d3a1761390d6692db (MD5) / Tese (Doutoramento) / IPEN/T / Escola Politecnica, Universidade de Sao Paulo - POLI/USP

Please read the abstract in the dissertation. / Dissertation (MSc)--University of Pretoria, 1965. / gm2014 / Electrical, Electronic and Computer Engineering / Unrestricted

Drop-in centers for individuals with serious and persistent mental illness offer a unique and perhaps under-recognized environment option for adjunct treatment. The current study examines and evaluates components thought to be a part of an enriched drop-in center experience that contribute to positive member outcomes through the effects of empowerment. These components include self-help, peer support, and creative expression. Outcomes were evaluated based on quality of life, self-worth, and symptom reduction. Such data are necessary in promoting the growth and development of drop-in centers and identification of components that contribute to positive member outcomes. Participants (n=101) were administered a series of measures including The Multidimensional Scale of Perceived Social Support, The Empowerment Scale, The Rosenberg Self-Esteem Scale, The World Health Organization Quality of Life-BREF, The BASIS-32™, and a series of questions created for the purposes of the current study regarding creative expression and self-help. The psychometric properties of each measure were evaluated and reviewed. Additionally, mean differences between normative data and participant means were examined and demographic data were analyzed. It was hypothesized from the literature that self-help, peer support, and creative expression would have significant indirect effects on all of the proposed outcome variables through the effects of empowerment. Results revealed significant indirect relationships between peer support and all of the outcome variables through the effects of empowerment and between self-help and all of the outcome variables through the effects of empowerment. No significant relationships were found between creative expression and any of the outcome variables through the effects of empowerment. These findings suggest that peer support and self-help may be instrumental in achieving positive outcomes through the effects of empowerment. Centers that offer experiences to enhance self-help and peer support will subsequently enhance feelings of empowerment in members, which relates to higher levels of self-worth, higher levels of quality of life, and lower levels of psychiatric symptomatology. Further implications of such findings and suggestions for continuation of this research are discussed in detail.

This diploma thesis is concerned with design and proposal of parameters of drop hammer Davon for crushing of steel reinforced concrete panels with weight of the ram 5 t. The main topic is an emergency condition when there is no crushed material between ram and anvil. The design is established by simulation of an impact by finite element analysis with respect to required ground bearing capacity.

This dissertation describes experiments on drop dynamics. It is split into two main parts: The first investigates the breakup of liquid during the impact of a drop on a pool surface, with focus on the smallest and fastest splashed satellite droplets. The second part studies the much slower coalescence of two minute water droplets in oil inside a micro-channel, with applications to separation of water droplets from crude oil emulsions. First, we study drop-on-liquid impacts in high-speed experiments with extreme time and spatial resolutions using up to 5 million frames-per-second video imaging. This is used to identify and explain two primary mechanisms which produce the smallest and fastest splashed secondary droplets, i.e. ejecta sheets and singular jets. Using a novel 25-m-tall vacuum tube we generate very large impact velocities, to reach regimes in parameter-space never studied before. During the earliest stage of the impact a fast-moving horizontal ejecta sheet emerges from the neck between drop and pool. The breakup of this sheet forms a myriad of micron-size droplets. The ejecta bending is dominated by air resistance, which we investigate under reduced ambient pressures and successfully model based on Bernoulli suction which pulls down the ejecta to hit the pool surface. The ejecta can initially bend up or down depending on the relative viscosities of the drop and pool, bending up if the pool is less viscous. Singular jets are produced by the collapse of drop-impact craters for deep pools, when a dimple forms at the bottom of the crater focusing the energy into a micron-sized region, with jetting velocities over 100 m/s. We use Gerris to study the fine details, obscured in the experiments. In the second part, we study the coalescence of water droplets inside an oil emulsion, developing an empirical relation between the coalescence interaction time tc and the modified shear-rate. This is done by tracking 3-D drop trajectories inside a microchannel, with two perpendicular high-speed cameras. For droplets in crude oil, we implement near-infrared visualization in an innovative device to quantify demulsifier efficiency, using mono-disperse micro-droplets.

One of two project reports. The other one is designated PART A: McMASTER (ON-CAMPUS) PROJECT / <p> A reactivity meter code based on point kinetics was developed. Rod-drop experiments performed in the ZED-2 reactor tested the code for various detector and rod-drop positions. A delayed neutron hold-up effect was observed whenever a rod was dropped close to a detector. A better understanding of this effect was obtained through a theoretical analysis of the pertinent experiments. The three-dimensional kinetics code, CERBERUS, was used for the theoretical analysis. </p> / Thesis / Master of Engineering (MEngr)

A drop tower is a device that produces a microgravity environment by allowing an experiment to free fall for a short period of time, usually less than 10 seconds. Certain types of drop towers are also capable of reproducing the gravitational conditions of other celestial bodies, such as Lunar and Martian gravity. Microgravity environments are often required for many different scientific experiments, such as experiments in material science, fluid dynamics, biological studies and many other fields. Microgravity environments are also often used as a specialized manufacturing method for certain materials. Components and systems that will be used in space or onboard sounding rockets can also be tested and verified using drop towers before launch. There is an ever-present need to conduct experiments in a microgravity environment and thus highlights the importance and relevance of drop towers in research and design verification. Other microgravity facilities such as sounding rockets, parabolic flights and orbital spacecraft typically provide longer microgravity durations, however, come at a considerable cost. This highlights the need for drop towers that are cost-effective as a desirable research device. This thesis consists of a comprehensive, systematic literature review to determine industry standards and the current state of the art in the world of drop towers. The different potential mechanical designs of a drop tower are then analyzed and trade-offs are completed. The most suitable design, that could feasibly be built at Luleå University of Technology (LTU)’s space campus, is chosen and presented later in this thesis. The safety of the drop tower was of utmost concern when deciding on the most suitable design as well as when completing the mechanical design of the drop tower. The slider is a major component of a drop tower, it houses the experiment and is a critical component in determining the achievable microgravity quality. The slider design was also analyzed with a trade-off analysis of the potential existing designs, with the most feasible design being chosen. The drop tower is planned to be installed in the LTU Spacecampus light garden which can accommodate a drop tower of approximately 13m in height. The mechanical design is verified using various Finite Element Analysis (FEA) simulations. The 14m planned and designed drop tower is a non-vacuum, guided design which would provide approximately 3 seconds of microgravity, 5.2 seconds of Martian simulated gravity and 7.8 seconds of Lunar simulated gravity. The drop tower has been designed to accommodate projects that are part of the REXUS program. The towers' considerable size and ease of use would make it suitable for many research institutions and many potential scientific studies.

Three existing pressure-drop models are validated and analyzed with experimental data compiled from the research database. From the analysis, it was found that the pressure-drop prediction results from the models are not very accurate and not consistent with all experimental datasets. A new pressure-drop model was consequently created based on the findings from the study, and experimental data from the database were used to validate the model to produce more accurate and consistent predictions. The new pressure-drop model was tested on experimental datasets that were in the database and also with experimental datasets that were not in the database. Good and consistent results were achieved, and the new model proved capable of predicting pressure drops for different pure refrigerants and refrigerant mixtures flowing inside different configurations of microin tubes for both condensation and evaporation.