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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.
11

Juvenile Delinquency as a Function of Level of Aspiration

Hampton, Dan 08 1900 (has links)
This study evaluates the anomie theory of juvenile delinquency with empirical data drawn from a sample population of junior and senior high school students. This research originates from the findings published by Bernard Rosenberg and Harry Silverstein in The Varieties of Delinquent Experience, a portion of which this study partially replicates.
12

Effect of Emotional Stimulation on Recognition and Inference

Haddan, Eugene E. 08 1900 (has links)
The purpose of this study was to make an assessment of the probable effects of extraneous stimulation on both cognitive achievement or learning, and emotional reactions and autonomic arousals of students. While the focus of interest was upon possible disruptive effects, the kinds of measurements projected would make it possible to observe some effects of either kind, disruptive or facilitative.
13

The Rooney Rule: Affirmative Action Policy and Institutional Discrimination in the National Football League

Smith, Erica R. 23 December 2008 (has links)
African American underrepresentation in positions of power within the intercollegiate and professional sports hierarchy continues to be a major concern among the media, professional sports organizations, and academic researchers. Although African Americans dominate the rosters of college and professional football teams, they remain grossly underrepresented in the management ranks. In 2002, the NFL designed a diversity plan that is commonly referred to as the "Rooney Rule" in order to increase the recruitment of African-Americans in head coaching positions. This dissertation is based on an examination of the impact of this policy in fostering diversity in NFL hiring patterns for the pre- and post- Rooney Rule eras. The study's objectives were (1) to examine the effectiveness of the Rooney Rule in increasing the hiring of African-American head coaches and (2) to identify and describe the factors and mechanisms that function to either enhance or impede mobility for minority candidates. To achieve these aims data was compiled from a variety of archival sources, including NFL and news media records. Furthermore, an integrative theoretical model was developed to assess the previously overlooked factors, particularly job authority, affecting mobility for minorities. The results revealed that the Rooney Rule has been effective in increasing the number of African-American coaches interviewed and ultimately hired as NFL head coaches. However, it was also found that there are more factors that impede rather than enhance mobility opportunities within the management ranks of the NFL. The integrative theoretical model predicted that race would play a role in a candidate receiving consideration for and being hired for a high authority, high power job. It was concluded that the factor that predicts mobility the most, as assessed by hiring, is authority level; which is the area in which African-Americans are underrepresented, thus leading to decreased chances of being interviewed or hired. Analyses indicated that African-American coaches are found in the less powerful coaching positions, are offered fewer interviews, and are hired less frequently; providing support for the argument that race continues to be important in the connection between leadership and selection for management positions.
14

Molecular Level Studies of the Metal/Atmosphere Interface

Weissenrieder, Jonas January 2003 (has links)
The chemistry andphysics involved at the metal/atmosphereinterface is interesting both from a fundamental and an appliedperspective. Since iron is the most important of all metalsthis interface is of particular interest. The objective withthis thesis is to obtain new information on a molecular levelof the iron/atmosphere interface with a special emphasis on theinitial atmospheric corrosion. The work presented herein combines a large variety ofdifferent analytical surface science techniques. Both ultrahigh vacuum and ambient pressure investigations were conductedwith single crystals as well as polycrystalline samples. The interaction of segregated sulfur with a Fe(110) surfacewas investigated by means of atomically resolved scanningtunneling microscopy (STM). A large variety of high and lowcoverage reconstructions were reported. Comparable studies ofoxygen adsorption on the same surface were also completed.Similar to the sulfur experiments, oxygen induced a number oflow coverage reconstructions. At higher coverage, oxideformation was observed and ordered oxides could be fabricatedat elevated temperatures. The oxygen interaction with Fe(110) and Fe(100) surfaces wasalso investigated with synchrotron radiation basedphotoelectron spectroscopy. Detailed information of the initialadsorption and subsequent oxidation was obtained. The Fe 2pcore level of the clean Fe(110) surface was subject to furtherinvestigations because of its complicated line profile that wasinterpreted as an exchange split of the final state. Iron exposed to humidified air with low concentrations ofsulfur dioxide (SO2) shows a surprisingly passive behavior. Themeasured mass gain was significantly lower than that of acopper sample exposed in the same environment. In-situtechniques such as atomic force microscopy (AFM), quartzcrystal microbalance (QCM) and infrared reflection absorptionspectroscopy (IRAS) showed little or no corrosion. Initiationof corrosion was observed upon introduction of additionaloxidants. The conclusion drawn challenge the established modelfor formation and growth of sulfate nests. The condition andformation of sulfate nests are discussed in view of thegenerated in-situ observations. During further experiments, iron was exposed to humid airand sodium chloride aerosols. The surface was investigated within-situ techniques, which provided new useful information. Ahigh corrosion rate was observed and the corrosion attacks formfilaments characteristic of filiform corrosion. A schematicmodel for propagation of the corrosion filaments wasproposed. Filiform corrosion was observed on aluminum surfaces aswell. The corroded surfaces were investigated with synchrotronradiation based photoelectron microscopy and scanning over afiliform head revealed different oxidation states within the Al2p spectrum. The microscopy data was interpreted as anenrichment of aluminum chloride containing compounds within thefiliform corrosion head.
15

Expansion Planning of Distribution Systems Considering Distributed Generation and Reliability Cost

Chiu, Shian-Chun 06 July 2009 (has links)
This thesis investigates the capacity expansion of distribution substation of each service area considering PV system penetration to achieve the cost effectiveness of substation investment to comply with the service reliability. With the land use planning of Kaohsiung City Government, the load density of each small area for the target year is derived according to the final floor area and development strength of the land base. The load forecasting of each small area is then solved by considering the load growth of each customer class and a Markov model is applied for the forecasting of solar energy, which is then included in the expansion planning of substations. The forecasting of annual peak loadings for each area over the future 20 years is performed by the time series method based on the historical load data and load type of customers served. The forced outage rate ¡]FOR¡^ of main transformers in the substations is used to solve the loss of load expectation¡]LOLE¡^ according to the peak loading of each service area. By this way, the capacity expansion planning of main transformers to meet the service reliability can therefore be derived. To further enhance the distribution system planning, the capacity transfer capability of main transformers and the tie line flow capacity between different areas are considered too. It is found that the expansion planning of main transformers by the proposed methodology can provide better cost effectiveness of transformer investment to satisfy the service reliability as well as the system peak loading.
16

Molecular Level Studies of the Metal/Atmosphere Interface

Weissenrieder, Jonas January 2003 (has links)
<p>The chemistry andphysics involved at the metal/atmosphereinterface is interesting both from a fundamental and an appliedperspective. Since iron is the most important of all metalsthis interface is of particular interest. The objective withthis thesis is to obtain new information on a molecular levelof the iron/atmosphere interface with a special emphasis on theinitial atmospheric corrosion.</p><p>The work presented herein combines a large variety ofdifferent analytical surface science techniques. Both ultrahigh vacuum and ambient pressure investigations were conductedwith single crystals as well as polycrystalline samples.</p><p>The interaction of segregated sulfur with a Fe(110) surfacewas investigated by means of atomically resolved scanningtunneling microscopy (STM). A large variety of high and lowcoverage reconstructions were reported. Comparable studies ofoxygen adsorption on the same surface were also completed.Similar to the sulfur experiments, oxygen induced a number oflow coverage reconstructions. At higher coverage, oxideformation was observed and ordered oxides could be fabricatedat elevated temperatures.</p><p>The oxygen interaction with Fe(110) and Fe(100) surfaces wasalso investigated with synchrotron radiation basedphotoelectron spectroscopy. Detailed information of the initialadsorption and subsequent oxidation was obtained. The Fe 2pcore level of the clean Fe(110) surface was subject to furtherinvestigations because of its complicated line profile that wasinterpreted as an exchange split of the final state.</p><p>Iron exposed to humidified air with low concentrations ofsulfur dioxide (SO2) shows a surprisingly passive behavior. Themeasured mass gain was significantly lower than that of acopper sample exposed in the same environment. In-situtechniques such as atomic force microscopy (AFM), quartzcrystal microbalance (QCM) and infrared reflection absorptionspectroscopy (IRAS) showed little or no corrosion. Initiationof corrosion was observed upon introduction of additionaloxidants. The conclusion drawn challenge the established modelfor formation and growth of sulfate nests. The condition andformation of sulfate nests are discussed in view of thegenerated in-situ observations.</p><p>During further experiments, iron was exposed to humid airand sodium chloride aerosols. The surface was investigated within-situ techniques, which provided new useful information. Ahigh corrosion rate was observed and the corrosion attacks formfilaments characteristic of filiform corrosion. A schematicmodel for propagation of the corrosion filaments wasproposed.</p><p>Filiform corrosion was observed on aluminum surfaces aswell. The corroded surfaces were investigated with synchrotronradiation based photoelectron microscopy and scanning over afiliform head revealed different oxidation states within the Al2p spectrum. The microscopy data was interpreted as anenrichment of aluminum chloride containing compounds within thefiliform corrosion head.</p>
17

Locally adaptive speed functions for level set methods in image segmentation

Rink, Karsten January 2009 (has links)
Zugl.: Magdeburg, Univ., Diss., 2009
18

Late Holocene sea-level change around Newfoundland /

Daly, Julia F., January 2002 (has links)
Thesis (Ph. D.) in Geological Sciences--University of Maine, 2002. / Includes vita. Includes bibliographical references (leaves 141-149).
19

Design as interactions of problem framing and problem solving : a formal and empirical basis for problem framing in design

Dzbor, Martin January 2002 (has links)
In this thesis, I present, illustrate and empirically validate a novel approach to modelling and explaining design process. The main outcome of this work is the formal definition of the problem framing, and the formulation of a recursive model of framing in design. The model (code-named RFD), represents a formalisation of a grey area in the science of design, and sees the design process as a recursive interaction of problem framing and problem solving. The proposed approach is based upon a phenomenon introduced in cognitive science and known as (reflective) solution talkback. Previously, there were no formalisations of the knowledge interactions occurring within this complex reasoning operation. The recursive model is thus an attempt to express the existing knowledge in a formal and structured manner. In spite of rather abstract, knowledge level on which the model is defined, it is a firm step in the clarification of design process. The RFD model is applied to the knowledge-level description of the conducted experimental study that is annotated and analysed in the defined terminology. Eventually, several schemas implied by the model are identified, exemplified, and elaborated to reflect the empirical results. The model features the mutual interaction of predicates ‘specifies’ and ‘satisfies’. The first asserts that a certain set of explicit statements is sufficient for expressing relevant desired states the design is aiming to achieve. The validity of predicate ‘specifies’ might not be provable directly in any problem solving theory. A particular specification can be upheld or rejected only by drawing upon the validity of a complementary predicate ‘satisfies’ and the (un-)acceptability of the considered candidate solution (e.g. technological artefact, product). It is the role of the predicate ‘satisfies’ to find and derive such a candidate solution. The predicates ‘specifies’ and ‘satisfies’ are contextually bound and can be evaluated only within a particular conceptual frame. Thus, a solution to the design problem is sound and admissible with respect to an explicit commitment to a particular specification and design frame. The role of the predicate ‘acceptable’ is to compare the admissible solutions and frames against the ‘real’ design problem. As if it answered the question: “Is this solution really what I wanted/intended?” Furthermore, I propose a set of principled schemas on the conceptual (knowledge) level with an aim to make the interactive patterns of the design process explicit. These conceptual schemas are elicited from the rigorous experiments that utilised the structured and principled approach to recording the designer’s conceptual reasoning steps and decisions. They include • the refinement of an explicit problem specification within a conceptual frame; • the refinement of an explicit problem specification using a re-framed reference; and • the conceptual re-framing (i.e. the identification and articulation of new conceptual terms) Since the conceptual schemas reflect the sequence of the ‘typical’ decisions the designer may make during the design process, there is no single, symbol-level method for the implementation of these conceptual patterns. Thus, when one decides to follow the abstract patterns and schemas, this abstract model alone can foster a principled design on the knowledge level. It must be acknowledged that for the purpose of computer-based support, these abstract schemas need to be turned into operational models and consequently suitable methods. However, such operational perspective was beyond the time and resource constraints placed on this research.
20

Experience of control and level of aspiration

Stone, Paula Creighton, 1943- January 1969 (has links)
No description available.

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