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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Hot, våld och djurskydd

Persson, Anneli January 2011 (has links)
This thesis examines the presence of threats and violence directed towards animal welfare inspectors/ officers. The main tool is a survey regarding threats and violence directed at animal welfare inspectors/officers. The questionnaire was distributed to animal welfare inspectors/ officers who worked on 15 of the country's 21 provincial governments. The response rate of the survey was 68.9 percent. The main conclusion of the study is that threats and violence directed at animal welfare inspectors/ officers are common. 94 percent of those who responded participated in the survey felt that there were threats of violence at their workplace and 26 percent felt that there was violence in the workplace. Threats and violence were more common against women and young people but neither of the differences was statistically significant. An additional conclusion that is made is that a large number of the animal welfare inspectors/ officers do not feel that they have the support they deserve from their employers.
22

Hot och våld i socialarbetares yrkesutövning : Threats and violence in the socialwelfare secretary occupation.

Nygårds, Annelie, Sandberg, Malin January 2009 (has links)
2004, the SSR, Akademikerförbundet, made a study on the threats and violence as a social secretary in the municipal social services are exposed in their occupation of the "social secretary of threats and violence at work" (T-110192), conducted by Temo ab. We have chosen to use the study on a smaller scale and then made contact with five municipalities in the middle of Sweden to investigate social secretaries experiences of threats and violence. Using the cross-sectional design and a convenience sample, we have gained access to data from 56 people. From a sociological perspective, we have chosen to use Norbert Elias theory of universal configuration and interdependence, and Michel Foucault’s theories concerning power search explanation for the existence of threats and violent situations in the contact between social workers and their clients.
23

Potential shift from transit to single occupancy vehicle due to adaptation of a high occupancy vehicle lane to a high occupancy toll lane

Chum, Geoffrey Linus 15 May 2009 (has links)
Modifying a high occupancy vehicle (HOV) lane into a high occupancy/toll (HOT) lane generally involves allowing single occupant vehicles (SOVs) to travel on the free-flow HOV lane for a toll. This may entice some former transit riders to pay the toll to obtain the benefits of traveling in their own vehicle on the HOV lane. Thus, the introduction of a HOT lane has the potential to impact transit ridership, dramatically lowering the average vehicle occupancy of the lane. In 2003, surveys were distributed to park-and-ride bus passengers on the Katy Freeway and Northwest Freeway corridors in Houston. Passengers’ responses to questions regarding their trip characteristics, their socioeconomic characteristics, and stated preference scenarios were used to develop a mode choice model. To determine how transit passengers might react to a proposed HOT lane, HOT lane scenarios with varying tolls and travel time savings were simulated using this model. For all scenarios, only a small percentage of transit passengers were estimated to switch to driving alone on the HOV lane. Fewer people would switch during the peak period than during the off-peak period. Transit passengers shifting to SOV on the HOV lane would reduce the average vehicle occupancy (AVO) only about 1 percent to 2 percent. SOV drivers shifting from the general purpose lanes to the HOV lanes are likely to affect AVO much more. However, as long as free-flow conditions are maintained, this analysis shows that the HOV lane can be successfully adapted to a HOT lane and move more people, even if a few transit passengers choose to drive alone.
24

On the Study of Proton Exchange Membrane Fuel Cell¡XThe Fabrication and Application of MEA

Lee, Xuan-Cheng 31 July 2001 (has links)
Abstract The process of the Membrane Electrode Assembly in the Proton Exchange Membrane Fuel Cell and the controllable variables: the pressure, the temperature, and the time of the hot pressure in the producing period would be discussed here. The experimental result of the MEA revealed that for Nafion112 and Nafion117 membranes, the conditions under the hot pressure are the same in the temperature. However, the pressure used in Nafion112 should be lower than Nafion117. In this case, the better function of the MEA can be achieved. Because Nafion112 is thinner, its water in the process of the hot pressure would be lost with extreme ease. This has a very serious impact on the function of the MEA. Therefore, to improve the MEA¡¦s function, the MEA should be boiled by water after being fabricated. The outcome of the research showed that for the purpose of improving the function of the MEA, some humidifier structure adding to the design of STACK is necessary. In order to be familiar to the related practical skills of STACK, PEMFC is brought into use for an electric bicycle in this research. Because the maximum power of STACK is only 150W, which is almost equal to the one-third power of the electric bicycles available such as the 400W of GIANT-Lafree electric bicycle. Besides, the speed of the electric bicycle is too slow when it is operated by itself, but it will be run more smoothly by the means of the assistant power. If the PEMFC electric bicycle can make more useful STACK and be redesigned, not be composed as it used to be, the use of the PEMFC electric bicycle will be steadier, more efficient, and more beneficial to the environment.
25

Effect of Inlet Temperature Non-Uniformity on High-Pressure Turbine Performance

Smith, Craig I. 01 November 2010 (has links)
The temperature of the flow entering a high-pressure turbine stage is inherently non-uniform, as it is produced by several discrete, azimuthally-distributed combustors. In general, however, industrial simulations assume inlet temperature uniformity to simplify the preparation process and reduce computation time. The effects of a non-uniform inlet field on the performance of a commercial, transonic, single-stage, high-pressure, axial turbine with a curved inlet duct have been investigated numerically by performing URANS (Unsteady Reynolds-Averaged Navier-Stokes equations) simulations with the SST (Shear Stress Transport) turbulence model. By adjusting the alignment of the experimentally-based inlet temperature field with respect to the stator vanes, two clocking configurations were generated: a vane-impinging (VI) case , in which each hot streak impinged on a vane; and a mid-pitch (MP) case, in which each hot streak passed between two vanes. In the VI configuration, the hot streaks produced higher time-averaged heat load on the vanes and lower heat load on the blades. As the hot streaks in the VI case passed over the stator vanes, they also spread spanwise due to the actions of the casing passage vortices and the radial pressure gradient; this resulted in a stream entering the rotor with relatively low temperature variations. The hot streaks in the MP case were convected undisturbed past the relatively cool vane section. Relatively high time-averaged enthalpy values were found to occur on the pressure side of the blades in the MP configuration. The non-uniformity of the time-averaged enthalpy on the blade surfaces was lower in the VI configuration. The flow exiting the rotor section was much less non-uniform in the VI case, but differences in calculated efficiency were not significant. / Pratt & Whitney Canada, NSERC
26

A study of the turbulent flow of a high speed Coanda jet

Cutbill, Sue January 1998 (has links)
This thesis presents an experimental investigation into a compressible turbulent wall jet issuing from a slot, and flowing over a surface with streamwise curvature, followed by a plane wall recovery region. The purpose of this data was to provide suitable test cases to aid in the design and validation of turbulence models used for curved flow situations in computational fluid dynamics. The presence of streamwise curvature provides an extra rate of strain to the flow which effects both the mean flow field and the turbulence structure. The effects of curvature are dependent on the ratio of the slot width to the radius of curvature. The effects are increased with the magnitude of this ratio. Hot film anemometry was used to measure the mean flow and Reynolds stresses under six different flow regimes. Four experiments were performed using a constant slot to radius ratio, and the supply pressure ratio was varied. Two further experiments were performed at a constant pressure ratio, but at differing slot to radius ratios. In all cases, the extra rate of strain was found to increase the jet growth and velocity decay rates beyond those of a plane wall jet. 'History effects' were apparent where there was a change from flow with streamwise wall curvature to that without. The turbulence structure was found to require a finite distance along the recovery section before it reverts to a plane wall turbulence structure. The presence of the extra rate of strain, and the history effects at sudden changes in surface curvature, make strong demands on any turbulence model. Various turbulence models have been tested, and although no one turbulence model has proved robust enough for all flow situations, a number of models have been identified to provide superior performance under certain conditions. The use of a higher order numerical scheme has also been found to reduce the effects of numerical diffusion, leading to improvements in the predictions of the flow shock cell structure and the breakaway performance of the jet.
27

Geochemical evaluation of a mineralized fossil hot spring system, Eureka County, Nevada

Grahn, Howard Lance, January 1990 (has links) (PDF)
Thesis (M.S. - Geosciences)--University of Arizona, 1990. / Includes bibliographical references (leaves 151-156).
28

Temperature and light adaptations of Synechococcus isolates from a hot spring microbial community

Allewalt, Jessica Post. January 2004 (has links) (PDF)
Thesis (M.S.)--Montana State University--Bozeman, 2004. / Typescript. Chairperson, Graduate Committee: David M. Ward. Includes bibliographical references (leaves 60-65).
29

Possibilities of pre-heating water with the heat obtained by cooling milk in a wet-tank milk cooler /

Charity, Leon F. January 1952 (has links)
Thesis (M.S.)--Virginia Polytechnic Institute, 1952. / Vita. Includes bibliographical references (leaves 73-75). Also available via the Internet.
30

Die Nacheile im Völkerrecht /

Bose, Hasso von. January 1935 (has links)
Thesis (doctoral)--Georg-August-Universität zu Göttingen.

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