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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

Believing you have it worse than others: maximization- a coping strategy

Tiedeman, Karyn 06 June 2008 (has links)
The present research examined the use of a heretofore unstudied coping strategy in which people maximize negative life events they have experienced. Maximization is defined as the process of comparing oneself to others on the number or intensity of negative life events one is experiencing, with the goal of finding that one is experiencing more or worse negative life events in comparison to others. It was hypothesized that maximization arises, in part, from self-verification concerns. It should therefore be elicited when an individual's experienced distress is not validated by others following a stressful life event. In addition, it was proposed that maximization will occur at both the public and private levels. Two variables, adjustment and perceptions of embarrassment or stigma are proposed to moderate the relationship between self-verification and maximization behavior. An experiment was conducted using 83 undergraduate college students, (identified from mass testing), who scored either .80 standard deviations above (Positive Event condition, n=43) or .80 standard deviations below (Negative Event condition, n= 40) the mean on the Life Experiences Survey. During a group discussion with two confederates regarding the types of negative life events college students experience, participants were randomly assigned to receive one of two types of Feedback, Invalidation or No Feedback. In the Invalidation condition, participants received information from the confederates that the confederates’ negative life experiences were more difficult in comparison to the participants. Participants in the No Feedback condition received no information regarding the negative life events they reported during the group discussion. The results suggest preliminary support for the proposal that the invalidation of distress following a negative life event(s) will elicit maximization behavior, both publicly and privately. Participants in the Negative Event/Invalidation condition, compared to the other three conditions, were significantly more likely to report during the group discussion that their experiences were worse than the confederates. Ona private measure of maximization, participants in the Negative Event/Invalidation condition, compared to the other three conditions, were significantly more likely to report that their experiences were worse than other Virginia Tech students. In addition, adjustment and perceptions of embarrassment significantly moderated the relationship between self-verification and maximization behavior, although the nature of the relationship differed for public and private behavior. Limitations of the experiment and future directions are discussed. / Ph. D.
22

Solid waste disposal and enforcement with an application to Virginia's scrap tires

Stedge, Gerald D. 06 June 2008 (has links)
This dissertation fills a void in the economics literature related to the effect of enforcement costs on solid waste disposal policy. The analysis demonstrates that the choice of a cost effective policy tool, be it either an enforcement mechanism or targeted subsidy, is an empirical question dependent on the particular attributes of the current waste disposal situation and the cost of enforcement. A solid waste disposal market simulation model is developed. The model is applied to the development of a policy aimed at solving Virginia's scrap tire disposal problem. The policy options considered are criminal enforcement, regulatory enforcement, and subsidies. The results of the case study indicate that in every case criminal enforcement is more expensive than regulatory enforcement. With regard to the question of what the role of enforcement versus subsidies should be, the most important indicator is the objective function. If the policy makers are concerned with total costs, and are not public budget constrained, then subsidies were found to dominate. If however, officials are concerned with gross or net public costs, due to a budget constraint, then enforcement dominates. The dissertation also documents the author's involvement in the development of Virginia's scrap tire management regulations. This experience shows that the model, although accurate, would only be useful as a policy development tool under certain conditions. Lastly, although this research provides a sophisticated means to determine least cost solutions to solid waste disposal problems, such as, used oil disposal, hazardous waste disposal, animal waste disposal, or human sludge disposal, it can be even more powerful as a means to demonstrate the need to consider the cost of enforcement when developing policy. / Ph. D.
23

The role of executive search consultants in the selection of school superintendents

Roberts, Mark Alan 26 October 2005 (has links)
The purposes of this study were to describe the role of executive search consultants in the superintendent selection process and compare their roles to the roles of executive search consultants in a previously conducted study. This study was patterned after a similar study completed in 1986, at the University of Wisconsin-Madison, by James Rickabaugh. Unlike the 1986 study, which concentrated on the Upper Mid-West region of the United States, this study was conducted using consultants from a geographic area consisting of Upper Mid-Atlantic states including: Massachusetts, New Hampshire, New York, Pennsylvania, Vermont, and Virginia. The role of executive search consultants from those states was compared with data from the 1986 study to determine whether the role of executive search consultants has changed or remained the same. / Ed. D.
24

Exploration of a Brunswik learning environment developed to instruct basic statistical concepts

Packard, Abbot Livermore 07 June 2006 (has links)
An ongoing debate persists of the value of computerized delivery of instructional material. At the center of this debate about the value of computer-assisted-instruction (CAI) is (1) the lack of a theoretical base and (2) the question of whether CAI influences the learner. Research begun by Brunswik allows the value of accommodation of individual learning preferences to be applied. CAI also has the capacity to supplement the presentation of textbook content and support educators using a multimodal approach to teaching that accommodates individual preferences. This study examined the development of an environment to presented stimulation which could add to the motivation of learners. This study investigated the relationship between the creation of a CAI learning environment based on Brunswik’s psychology and 102 master and doctoral students' cognitive styles. The study investigated the ability of two cognitive measures to predict the CAI presentation method best suited for an individual's cognitive ability. Two different cognitive measures were regressed against three different CAI presentation methods (text only, text and static graphics, and text and animated graphics). These three different methods were used for delivery of a basic instructional design since they were simple for the user to follow and easily created via a multimedia environment for the designer. Instruction using these methods was limited to three content areas: random sampling, systematic sampling, and skewness of distribution. An Aptitude-Treatment-Interaction (ATI) analysis was used to study the interaction between participants' cognitive attributes and CAI presentation types. While a significant effect was not found in most of the recall tests, many disordinal interactions demonstrated tendencies that warranted further study. An ANCOVA was also performed using the total immediate recall scores showing significant differences among the CAI presentation types. The results of a one-way ANOVA found that participants assigned to the text only CAI presentation method tested better than their counterparts using the graphic additions to the textual instruction. / Ph. D.
25

Ethics and the secondary school social studies teacher

Rogers, Catherine S. 22 December 2005 (has links)
The purposes of this study were to examine how teachers responded to ethical issues in the workplace and to prepare materials for use in teacher training and staff development programs. To determine teacher responses to certain ethical situations, twenty open-ended scenarios describing ethical situations were developed. Twenty social studies teachers from school divisions with 25,000 students or more and twenty social studies teachers from school divisions with 3,500 students or less were selected and on-site interviews were conducted with each teacher responding to four randomly selected scenarios. Responses were transcribed, analyzed, and distilled. The twenty scenarios and the teachers' responses were then used as a basis for the development of materials for teacher preparation programs for one college and staff development programs for one school division. All but two scenarios reflected a difference between what teachers perceived to be the action most taken by teachers and the action perceived to be the most ethical. Responses by teachers to ethical situations revealed that potential and practicing teachers would benefit by the study of professional ethics in their professional preparation program. / Ed. D.
26

The school board and self-evaluation: do school boards in the Commonwealth of Virginia evaluate their own performance?

Martin, John A. 14 August 2006 (has links)
School boards are the governing bodies for school divisions. Their successful operation is essential to the success of the school division. "Best practice", as indicated in the literature, calls for school boards to recognize the need to examine or assess their own performance and to set the criteria or goals by which they will evaluate their performance and to create a composite of strengths and weaknesses in relation to the criteria they set for themselves. Boards should design or select evaluation instruments which reflect local performance criteria and instruments that are open ended so that other items may be included as board members desire. The development of objectives for the improvement of the boards' performance should be based on an evaluation of themselves discussed and agreed to in a regularly scheduled annual meeting with a facilitator and site for the event predetermined. Finally, the process should be focused on the board as a body; not on the individual board members. This study solicited information describing the practices of school boards in Virginia relative to evaluation of themselves as boards and compared those practices with literature-based "best practice." Defining "best practice" was accomplished by reviewing educational literature on the practice of board evaluation. The literature was screened for components recommended as required in effective school board self-evaluation. Components recommended as effective practice were determined to be "best practice." The questionnaire was designed in two sections. The first grouping of questions on the survey was to identify the divisions where school boards practiced self-evaluation. Subsequent queries, in section two, gathered information that would allow description of the practices used by school boards who practiced self-evaluation. Section two, also, posed questions regarding the boards' use of procedures that were determined to be components of "best practice". A survey questionnaire was mailed to the superintendents of all 132 school divisions in Virginia inquiring about their board's practices of evaluating their own performance. Responses were received from 128 of the 132 divisions, a 97% rate of return. Only forty-one (32%) of the responding school divisions reported having school boards that evaluate themselves. Are school boards in the Commonwealth evaluating their own performance? The major findings of this study indicate that most school boards in Virginia, more than two out of three, do not practice school board evaluation. School boards in Virginia that allege participation in the practice of school board evaluation do not use many of the components of self-evaluation recommended as "best practice". School board evaluation is used less often in those divisions of medium size than in other divisions and less often in those divisions associated with counties as their governing units than in other divisions associated with other types of governing units. / Ed. D.
27

Molecular investigation of the wood/pMDI adhesive bondline

Ni, Jianwen 04 October 2006 (has links)
Polymeric diphenylmethane diisocyanate, pMDI, has become an important wood binder in recent years, due to its excellent performance in wood-based composites. However, much still remains unknown about the nature of their bonding mechanism. This research describes efforts to learn more molecular information about the pMDI-wood bondline, and to further improve the bonding performance. In order to correlate molecular phenomena with macroscopic performance of wood-adhesive bondline, low frequency molecular motions in wood were probed using dynamic mechanical analysis (DMA) and ¹³C cross-polarization, magic-angle spinning (CP/MAS) NMR. A correlation between the CP time constant <T<sub>c</sub><sub>h</sub>* and the dynamic storage modulus E’ was established for dry wood, but was not valid for wet wood samples. Two types of pMDI with properties similar to commercial resins, except for isomer ratio, was synthesized. The one with isomer ratio similar to commercial resins was analyzed with ¹⁵N CP/MAS NMR. The results show that the pMDI-wood bondline is a heterogeneous complex of urethanes, polyureas, residual isocyanates and biurets. The network structure is controlled by the curing variables such as temperature and time. Urethane formation was detected under relatively mild cure conditions. Thermal decomposition of urethanes (120°C) and polyurets (185°C) were detected. ¹⁵N NMR was demonstrated as a powerful technique, but suffers from signal overlap which prevents a clear evaluation of the relative contributions of urethane and urea formation. Another type of pMDI with higher 2,4’- isomer content was used to investigate the effects of isomer ratio on bonding mechanism. The chemical species found in the heterogeneous bondline are similar, except that urethane formation is less evident here. Relaxation studies show very different behaviors, in which the bondline with higher 2,4’- isomers may have a higher molecular mobility. A fracture toughness test method, contoured double cantilever beams (CDCB), was developed to evaluate the macroscopic performance. They both showed strong bonding, and there was no significant difference found. To explain the strong bonding of pMDI and wood, an interpenetrating polymer network (IPN) theory was hypothesized. ¹³C CP/MAS NMR and DMA were used to evaluate this hypothesis. The results were inconclusive due the limitations of the techniques. / Ph. D.
28

Synthesis and photophysical investigation of supramolecular complexes developed for photoinitiated electron collection

Molnar, Sharon Marie 26 October 2005 (has links)
In this research, photochemical molecular devices were designed to perform photoinitiated electron collection. These devices were synthesized, characterized and their spectroscopic, photochemical and electrochemical properties investigated. The general formula for these systems is {[(bpy)₂Ru(BL)]₂MCl₂}⁵⁺ (M = Ir<sup>III</sup> and BL = dpq (2,3-bis(2- pyridyl)quinoxaline) or dpb (2,3-bis(2-pyridyl)benzoquinoxaline), or M = Rh<sup>III</sup>, BL = dpp (2,3-bis(2-pyridyl)pyrazine)). The functioning of these devices as photoinitiated electron collectors was determined. Through the use of a sacrificial electron donor in a photolysis experiment, the functioning of the {[(bpy)₂Ru(dpb)]₂IrCl₂}⁵⁺ trimetallic complex as a photochemical molecular device for photoinitiated electron collection was established. The interaction of the electron donor with the trimetallic complex was also investigated through a Stern-Volmer quenching study. To tune the properties of the chromophoric units, [Ru₂(bpy)(BL)]²⁺, the bridging ligand was varied. The dpq bridging ligand was modified through the incorporation of electron donating and electron withdrawing substituents. The 6,7-dimethyl-2,3-bis(2’- pyridyl)quinoxaline and 6,7-chloro-2,3-bis(2’-pyridyl)quinoxaline bridging ligands were synthesized and characterized. The ruthenium mono- and bimetallic complexes utilizing these bridging ligands, as well as dpb, were synthesized and investigated. It was shown that the light absorbing and electrochemical properties of these [Ru(bpy)₂(BL)]²⁺ chromophores can be varied by altering the π-acceptor nature of the bridging ligand. / Ph. D.
29

Decision support system for locating traffic information dissemination sites along freeway corridors

Nutakor, Christopher 14 August 2006 (has links)
Dynamic route guidance systems which are products of the Intelligent Transportation Systems (ITS) Technology have been reasonably useful in guiding motorists from their origins to destinations. In general, transportation networks could be used more efficiently if dynamic route guidance information could be provided to motorists at all relevant locations along freeway corridors. This is however not possible, particularly because of financial constraints. It is therefore imperative that information be provided to motorists at locations where it will be of maximum benefit. The objective of this research is to develop methodologies and computer models for estimating utility of motorist information at different locations along freeway corridors. Such models will be very useful in guiding transportation professionals to optimize resources when providing guidance information to motorists. The methodologies have been developed based on both recurrent and non recurrent traffic congestion situations. The methodologies assume that motorists behave rationally and will divert from congested freeways to uncongested arterials based on the user equilibrium traffic assignment criteria. The utility of information estimation has however been based on total system time savings. Computer models have been developed based on the methodologies using the C++ programming language. Nonetheless, because the computer models have been developed based on historical traffic data, they have been validated using real time simulation models developed with the SIMSCRIPT II.5 programming language. The validation process proved reasonably successful. Many factors which include traffic volumes on alternate arterial routes to a given freeway link, the number of alternate routes to the freeway link especially under recurrent traffic congestion conditions, link lengths, volume of traffic on the freeway link and incident history in the case of non recurrent congestions influence the utility of information. With the particular networks investigated in this research however, the results indicate volume of traffic on the freeway links as the most influencing factor, since freeway links with relatively high traffic volumes tend to have relatively high utility values. The reason for this is probably because of the small size nature of the networks used, hence as a result all the freeway links tend to have only one or two alternate routes and the traffic volumes on the arterial links also do not differ significantly. The freeway link volumes therefore become the dominating factor in influencing the information utilities. / Ph. D.
30

Predictors of psychological distress and well-being in the caregivers of children with or at-risk for HIV infection

Miller, Kathryn M. 22 December 2005 (has links)
Assessed the contribution of demographic, illness, and psychosocial parameters to the psychological adjustment of 64 caregivers of children with or at risk for HIV infection. As a group, caregivers reported a significantly greater level of psychological distress than the general population while the level of well-being reported by caregivers was similar to that of the general population. Illness and demographic parameters failed to significantly predict aspects of caregiver adjustment, together accounting for only six and nine percent of the variance in caregiver psychological distress and well-being, respectively. Psychosocial variables, however, contributed significant increments in the variance of both domains of caregiver adjustment. Specifically, higher levels of caregiver psychological distress were associated with poorer caregiver health status, greater number of coping strategies reported, and higher levels of family conflict. Higher levels of caregiver well-being were associated with perceptions of less impact of negative life events, lower levels of family conflict, and greater perceptions of emotional support. Implications for future research and intervention are discussed. / Ph. D.

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