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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.
41

A study of legal information needs of public higher education administrators in the District of Columbia

Green, John Edward Milton January 1975 (has links)
This study was concerned with the assessment and analysis of legal information needs of the major administrators in the public higher education system of the District of Columbia. The study further sought to provide a model Request for Proposal (RFP) with a performance specification suitable for inclusion in a public contract which ultimately would result in a study and handbook of the identified legal aspects. The administrators' needs and desires for legal information were assessed through a questionnaire survey. The questionnaire was divided into three section emphasizing: a. What information was generally known. b. What additional information was needed. c. What information was desired. Results of the survey indicated that there was a generally low awareness of the more popular aspects of college and university law. However, the administrators appeared to be generally aware of the specific legal aspects pertaining to the instruction or classroom activity. Most of the administrators felt that they were not equipped with sufficient legal information to make decisions on matters with legal implication that could withstand a challenge in court. Constitutional rights, employment contracting, fiscal administration, and policy conflicts were viewed as the most frequent problem areas, while accreditation and tenure problems were viewed as the least frequent. The survey also resulted in a priority listing of legal topics for which additional information was desired. The survey results were used as a basis for developing a draft outline of legal information topics and sub-topics for inclusion in a study and handbook. A panel of experts in higher education administration and law was effective in producing a final qualified outline. Using the final topic outline, a draft model RFP, containing a performance specification, was designed. A second panel, comprised of experts in contracting, reviewed, modified and validated the model RFP as being usable to actually obtain the required services through a public contract, to conduct a study and produce a handbook with emphasis upon the District of Columbia public higher education system. It was concluded that: a. Administrators of the public colleges in the District of Columbia do want and need additional legal information. b. Administrators of the public colleges in the District of Columbia can specifically identify their needs and desires for legal information. c. Expressed or identified legal information needs can be converted into a public contract performance specification. Key recommendations for further study included the development of objective evaluation criteria applicable to performance contracts and the actualization of the study results by the appropriate offices of the District of Columbia Government. / Ed. D.
42

A test of Holland's hexagonal model of occupational classification using an inner-city high school population

Meadows, Ferguson B. January 1975 (has links)
John L. Holland has developed a theory which states that people can be characterized by their resemblance to each of six personality types: realistic, investigative, artistic, social, enterprising, and conventional. Holland further indicates that the environments in which people live can be characterized by their resemblance to six model environments which correspond to the six personality types. Finally, the pairing of persons and environments leads to predictable outcomes relative to vocational choice, vocational stability and achievement, educational choice, and susceptibility to influence. The purpose of this study was to determine the extent to which Holland's model of occupational classification could be applied to an inner-city high school population. In order to determine the applicability of Holland's model to the population being tested, four hypotheses were formulated. 1. There are significant relationships between the occupational classifications of Holland's model when applied to an inner city high school population. 2. There are significant relationships between the intercorrelations of the occupational classifications of Holland's national sample and the intercorrelationR of the occupational classifications of the present study. 3. There is a significant relationship between the rank ordering I of the intercorrelations of the occupational classifications of Holland's study and the rank ordering of the intercorrelations occupational classifications of the present study. 4. There are dominant personality types in an inner-city high school population as measured by the Vocational Preference Inventory. The subjects for the study were 492 high school sophomores (218 male, 274 female) from Region I of the Baltimore Public·School System. To test the first hypothesis, data collected by the VPI were treated by the correlation program BMDO3D. This treatment resulted in a correlation matrix. The data were then displayed on a hexagonal model. The relationships among the scales on the hexagon were treated by Spearman and Kendall correlation coefficients. The results indicated that the relationships were significant at the .001 level. The second hypothesis required a comparison of the hexagon which resulted from testing the first hypothesis with Holland's hexagonal model. The results revealed higher correlations among the six scales of the present study than for Holland's study. The third hypothesis was tested by treating the rank ordered correlations from the present study and Holland's model with the Spearman coefficient of rank correlation, The results indicated that the two rank orderings were significant at the .01 level. The fourth hypothesis 'Was tested by using the SPSS program Codebook. The results yielded means and standard deviations for male and female subjects. 'l'his made it possible to determine the three highest variables for male and female subjects. The dominant variables for the male subjects were Realistic, Enterprising, and Conventional, and for female subjects, social, Artistic, and Conventional. The results of statistically treating the data from this study revealed similarities between Holland's findings and the findings of this study. Thus, it could be suggested that the VP! is an appropriate instrument to use with inner-city high school students. / Ed. D.
43

An assessment of self-concept changes during first term attendance of students in a rural, Appalachian community college

Smith, Donald Howard January 1975 (has links)
The amount of change in self-concept during the first term of attendance of 267 students in a rural, Appalachian community college was explored. Sixteen subscales of the Tennessee Self-Concept Scale (TSCS) were employed, in a pre-test/post-test design, as the indicator of change in self-concept. Students were stratified by assignment to one of two groups within 11 demographic variables: Curricula, Age, Sex, Marital Status, Employment Status, Fathers I Education Level, Fathers' Occupation Level, Student Financial Aid, Special Services Program for the Disadvantaged, Level of Choice of the Community College, and Enrollment Status. The null hypotheses were tested by multivariate analysis of covariance (MANCOVA), univariate analysis of covariance (ANCOVA), and calculation of simultaneous confidence intervals. Adjusted mean scores of variable groups were compared through these statistical procedures, in order to discover if there were significant differences in self-concept change at an alpha level of .05. Significant differences were not noted at the .05 level, dictating a failure to reject the null hypotheses which stated that there would be no significant differences in the level of self-concept between the groups comprising the demographic variables. It was noted, however., that there were trends toward significant differences (p less than .10). The Total Positive Score subscale revealed significant differences at this level between 14 variable groups. The subscales of Self-Satisfaction, Physical Self, Distribution Scores, Identity, Personal Self, Social Self, Total Variability, and Self Criticism also yielded significant differences at this level., although between a lesser number of variable groups. Trends toward significant differences (p less than .10) were most evident on the variables of Age, Sex, Employment Status, Student Financial Aid, and on the comparison of the variable group combinations of Curricula/Fathers' Education Level. Exploration of self-concept change of the total sample., on each TSCS subscale, revealed a minor change, in a positive directio., on each subscale. Although self-concept is believed by many to be a major determinant of behavior and performance., findings of this study implied that self-concept development was not a principal classroom objective. It was also believed that since all subjects were commuting students., the environment which was external to the campus could have served as a counter-influence on individual self-concepts. Further investigation of this problem. using the TSCS and other self-report instruments. was recommended. / Doctor of Education
44

Effects of pumped storage project operations on the spawning success of centrarchid fishes in Leesville Lake, Virginia

Bennett, David H. January 1975 (has links)
Research was initiated in the spring of 1972 to evaluate the effects of the Smith Mountain Pumped Storage Project on the spawning success of centrarchid fishes in the lower impoundment, Leesville Lake. Hydroelectric power generation operations at the Smith Mountain Dam power plant create high water velocities with daily flow reversals, and water level and temperature fluctuations in Leesville Lake. Water levels in Leesville fluctuate as much as 3.5 m (11 ft) per day and 4 m (13 ft) per week during spawning periods of centrarchid fishes. In addition, daily intrusions of subsurface water from Smith Mountain Lake into Leesville Lake during periods of power generation average less than 20 C in temperature. At night and on weekends, surface waters from Leesville Lake are pumped back to Smith Mountain Lake. These project operations create three fluctuating, relatively unstable sections in Leesville Lake; a cool upper reservoir zone, a mid reservoir temperature mixing zone, and a warmer lower reservoir zone. Centrarchid fishes were collected from the three reservoir zones in Leesville Lake and gonads were examined. Generally, gonadal maturation and the presence of fish in spawning condition occurred earliest in the warmer lower zone, later in the mid reservoir, and last in the cooler upper zone of Leesville Lake during 1972 and 1974. During 1974, trained divers located and inspected 2010 centrarchid fish spawning nests in Leesville Lake. Based on a constant unit of diving effort, 40 percent of nests occurred in lower Leesville, 57 percent in mid, and about 3 percent in the upper reservoir zone. High water velocities restricted spawning activity in the mid and upper reservoir zones almost entirely to cove areas. Water velocities in lower Leesville had negligible effects on the distribution of spawning activity. A stepwise regression model indicated that water velocities during power generation at Smith Mountain Dam was the single most important factor affecting the distribution of spawning nests in the main lake. Vertical distribution of centrarchid fish spawning nests suggested that adjustment to the spawning depth had occurred in response to the fluctuation in water levels. Nearly 40 percent of all spawning nests in Leesville Lake were located 0.3 to 1.5 m below minimum pool elevation or about 4. 5 m below maximum pool level. Laboratory and field studies were conducted to evaluate hatching success of bluegill (Lepomis macrochirus) eggs under controlled water temperatures and exposures to air. Average hatching success increased as hatching temperatures increased from 16 to 28 C. Hatching success of naturally spawned bluegill eggs exposed during night and daytime hours in natural spawning nests in Leesville Lake decreased with increased exposure to air. SUCCESS, a computer-implemented mathematical model using data generated in this study, indicated that the average spawning success of bluegill would be about two times higher in the lower zone than in upper Leesville Lake. Predicted estimates of spawning success of bluegill for the entire reservoir were about 31 percent. Based on the current levels of exploitation, natural spawning success of largemouth bass and bluegill in Leesville Lake appears adequate to maintain the densities of these centrarchid fish stocks. / Ph. D.
45

Policy analysis relative to the employment of teacher aides in Virginia

Berry, Joseph Nelson January 1975 (has links)
In 1974 the state of Virginia began a legislative study of the methods utilized to fund teacher aides and developed accreditation standards for elementary and secondary schools permitting employment of teacher aides. Prior to this time, the Virginia State Department of Education had no state program for training or certification. However, it had suggested (in 1969) limited personnel policies for selection of teacher aides, which proved to be a stimulus for several local school districts in the state to develop limited personnel policies relating to the employment of teacher aides. This study was designed to present descriptive data concerning areas of existing local teacher aide personnel policy. The study also delineated, as normative data, those policy areas considered important for inclusion in future local and state guidelines. A study was made of the teacher aide policy handbooks received from an inquiry addressed to the directors of 141 local Career Opportunities Programs in the United States. Similarly, a study was made of the status of teacher aides as indicated in responses elicited from the Department of Certification and Teacher Training in each of the 50 states. With the data received from these studies, a three-part survey instrument was developed which contained 40 policy items under each of three major areas of concern, "current local policy," "opinion for future local policy," and "opinion for future state policy." An additional item was included to ascertain legal status and opinions relative to certification. The instrument was mailed to all (131) of the local district superintendents in Virginia, selected (24) administrative and instructional personnel in the Virginia State Department of Education, and all (67) of the teacher aides who were members of the Department of Teacher Aides, Virginia Education Association, in 1974. The rate of return for superintendents was 92.4 percent, for state department personnel, 87.5 percent, and for teacher aides, 61.2 percent. Statistical procedures of frequency distribution and percentage were utilized in analysis of the data. Of those items which are currently part of local policy, 15 were unanimously recommended for inclusion in both future local and state guidelines. Inclusion of 40 policy items was recommended by a majority of the superintendents for future local policy, while state department personnel recommended 38 and teacher aides, 34. For inclusion in future state policy, a majority of superintendents recommended 35 policy items, state department personnel, 22, and teacher aides, 33. The study revealed that for Virginia instructional teacher aides there should be developed a comprehensive set of local and state policy guidelines for training, certification and related personnel practices. These were seen as means of providing for shared accountability between state and local policymakers in those areas of funding and permanacy of the instructional teacher aide position. Policy guidelines for certification, training and related personnel areas have further implications for the individual instructional teacher aide. These were seen as means for providing greater job security, higher salaries, status, and availability of financial assistance for pre-service and in-service career training programs. / Ed. D.
46

A public choice analysis of millage issue elections for financing public schools

Holcombe, Randall G. January 1975 (has links)
In the relatively young sub-discipline of Public Choice, there are a number of theoretical models predicting the type of equilibrium that would be expected in the production of goods and services in the public sector. These models arrive at a number of different conclusions; but one major class of models predicts that public sector output will cater to the demands of the median voter, while another class of models predicts that the amount of public sector output will exceed that level most preferred by the median voter. More information can be generated about the nature of equilibrium in the production of public education than for most other goods and services produced in the public sector, because of the existence of millage issue elections that are held in many states. Two aspects of millage issue ·elections are emphasized in this analysis. First, millage issue elections . act as a constraint on the behavior of school boards, since the school board cannot enact a millage rate without first receiving the approval of the voters. Second, millage issue elections act as a revealed preference experiment, since voters are being asked to state their preferences on the millage issue presented in the referendum. These two aspects of millage issue elections generate information about the nature of equilibrium in the production of public education, and provide the basis for using millage issue elections as a vehicle for studying the nature of equilibrium in the production of public education. A model for interpreting the results of millage issue elections is developed, followed by a survey of institutional differences in public school finance from state to state. Some empirical propositions are forwarded, based on the hypothesis that there is a general tendency for school expenditures to exceed the level most preferred by the median voter. Two empirical analyses fail to support the propositions, but are in agreement with the results that would be expected if public education were being produced at close to the level most preferred by the median voter. / Ph. D.
47

The reaction of ortho-positronium with nitroaromatics via complex formation

Madia, William Juul January 1975 (has links)
A study was made to ascertain the mechanism by which ortho-positronium reacts with nitroaromatics in solution. These reactions are two to three orders of magnitude faster than expected by simple pickoff. Conjugation of the nitro group with the aromatic ring was found to be a necessary condition for this behavior. The rate constant for each of these reactions was measured in suitable solvents over a wide temperature range, 200-500°K. Distinct departure from the Arrhenius law was found. In general, the rate constant increased linearly with increasing temperature up to a point, and then decreased linearly as the temperature was raised further. The following mechanism is postulated: Ps + M [stacked right and left arrows with k₁ above and k₋₁ below] PsM [right arrow with k₂ above] M + 2γ. Ortho-Positronium reacts with the nitroaromatic, M, to form a complex in a reversible step. The complex may either decompose into a positronium atom and nitroaromatic molecule or it may go on to annihilate the positron. A steady-state concentration ot the complex is assumed and the observed rate constant for the process is K<sub>obs</sub> = k₁k₂ /(k₋₁+ k₂) The two limiting cases are: (1) k₂ >> k₋₁ causing k<sub>obs</sub> = k₁ . Typical Arrhenius behavior is expected and observed in this region, and (2) k₋₁ >> k₂ causing k<sub>obs</sub> = K<sub>EQ</sub>k₂ . In this region H<sub>EQ</sub> + E<sub>a</sub>(2) <O and the observed rate constant decreases with increasing temperature. This corresponds to a stable but temperature sensitive PsM complex. An approximate molecular orbital study has been made to study the possible existence of positron and positronium complexes with a select number of organic molecules. The CND0/2 approximation is used for all electronic integrals and for electron positron Coulomb integrals. The core Hamiltonian matrix elements for the positron were estimated by combining the Wolfsberg-Helmholtz and Cusachs-Cusachs approximations. This approach shows that the positron should become bound to the molecules. Using the same criteria, the formation of stable positronium complexes is more improbable. The calculated binding energies are strongly dependent on the value of the Wolfsberg-Helmholtz proportionality constant for positrons. / Doctor of Philosophy
48

Flutter of laminated plates in supersonic flow

Sawyer, James Wayne January 1975 (has links)
A procedure has been developed for solving flutter problems of simply supported laminated plates using linear small deflection theory. The plate construction may be arbitrary as long as it satisfies the assumptions of linear small deflection theory. For such plates, the bending and extensional governing equations are coupled and have cross-stiffness terms which do not appear in classical plate theory. The coupling and cross-stiffness terms occur as a result of the lamina principal directions (fibers) not coinciding with the neutral surface of the plate. The extended Galerkin method is used to obtain approximate solutions to the governing equations where the aerodynamic pressure loading used in the analysis is that given by linear piston theory with flow at arbitrary cross-flow angles. Flutter solutions were obtained for typical symmetric, angle-ply, and general laminated composite plates, and a limited parametric study was conducted. The parameters studied include the number, orientation, and orthotropy of the lamina; the plate length-width ratio; the inplane normal and shear loads; and the cross-flow angle. In addition, flutter solutions for several composite stiffened aluminum plate designs were obtained to determine the most flutter resistant design. The bending-extensional coupling and the cross-stiffness terms both have a large destabilizing effect on the flutter of unstressed laminated plates, but increasing the number of laminas, reducing the lamina orthotropy, and stacking the laminas in the"best" order reduce the destabilizing effect. For a square plate, aligning the fibers with the direction of flow (x-axis) results in the highest flutter stability, but for a plate with a length-width ratio of 2, large improvements in flutter stability may be obtained by rotating the fibers away from the x-axis. For angle-ply plates, inplane normal and shear loads and crossflow have a destabilizing effect on flutter similar to that obtained for orthotropic plates. However, for symmetric plates with the fibers not aligned with the x-axis, the cross-stiffness terms give rise to an improvement of the flutter stability with cross-flow angle. Flutter calculations for equivalent symmetric, angle-ply, and general unsymmetric plates indicate that for no cross-flow and no inplane shear loads, plates with an angle-ply construction will have the highest flutter stability. If cross-flow or inplane shear loads are present, symmetrically constructed plates may have higher flutter stability. Classical plate theory does not consider bending-extensional coupling and cross-stiffness terms, and therefore gives inaccurate and usually nonconservative flutter boundaries for laminated plates. Reduced bending stiffness theory, an approximate flutter theory which accounts for the coupling by reducing the plate bending stiffness as determined by the coupling terms and then neglects the coupling in solving the equations, gives flutter solutions that are adequate for all plates for which numerical results were obtained. / Doctor of Philosophy
49

Fluorosulfanylimination including related reactions and structural problems and thiazyl trifluoride complexes of the transition metals

Shanzer, Abraham January 1976 (has links)
This thesis reports the preparation of new pentafluorosulfanylimino (SF₅N=) derivatives, which have been synthesized from pentafluorosulfanyl isocyanate, SF₅NCO, pentafluorosulfanylamine, SF₅NH₂, and pentafluorosulfanyliminosulfur difluoride, SF₅N=SF₂. Reactions of SF₅NCO, SF₅N=SF₂, and SF₅NH₂, with appropriate substrates have produced SFN=S(CH₃)₂, SF₅N=CHC₆H₅, SF₅N=SCl₂, (SF5N=)₂C, (SF5N=)₂S and SF₅N=PCl₃, some of which are new compounds and some of which represent improved routes to compounds previously reported. When N,N'-bis(pentafluorosulfanyl)urea, (SF₅NH)₂CO, reacted with carbonyl fluoride SF₅NCO was formed. The reactivity of SF₅NCO in several basic reaction types including nucleophilic substitution, addition, exchange and coupling reactions was examined. Pentafluorosulfanyl isocyanate and dimethyl sulfoxide reacted to produce a crystalline product identified by its H-1 and F-19 nmr and in spectra as SF₅N-S(CH₃)₂. Pentafluorosulfanyl isocyanate and benzaldehyde reacted to produce a yellow solution and carbon dioxide. The solution was determined by spectroscopic mean to contain SF₅N=CHC₆H₅, a novel, electron-deficient Schiff base. Pentafluorosulfanylisocyanate and PCl5 reacted readily at 60-80° producing SF₅N=CCl₂ and POCl₃. A slow reaction between SF₅NCO and excess AgF₂ took place at room temperature. Infrared analysis of the reaction mixture at increasing temperatures gave evidence for formation and subsequent decomposition ofSF₅N=NSF₅. Pentafluorosulfanyliminosulfur difluoride (obtained from irradiation of N≡SF₃) reacted at room temperature with PCl₅ to produce SF₅N=SCl₂, a pale yellow liquid which rapidly attacked mercury, and reacted with AgF₂ (producing SF₅N=SF₂) and with SF₅NH₂(producing SF₅N=S=NSF₅). Pentafluorosulfanylamine, SF₅NH₂, and PCl₅ reacted at room temperature to give SF₅N=PCl₃ a pale yellow liquid which reacted rapidly with mercury. Thiazyl trifluoride reacted with metal carbonyls (Ni(Co)₄ , Fe(CO)₅, Mo(CO)₆, Mn(CO)₆) and ferrocene to produce thiazyl trifluoride - transition metal complexes. Chemical similarities between SF₅NCO and SF₅N=SF₂ with respect to nucleophilic substitution, exchange and coupling reaction reflect the similarity in bonding expected in these two systems. However, the failure of SF₅N=SF₂ and compounds containing the -N=SF₂ group to undergo additional reactions with polar reagents indicates some gross discrepancy from the usual behavior of these multiply bonded systems. Thus, a theoretical study of -N=SF₂ system was undertaken to clarify the role and magnitude of d-orbitals in the bonding of -N=SF₂ compounds. Theoretical calculations (CNDO) of the total energy of SF₅N=SF₂ , CF3N=SF₂ , C₂ F₅N=SF₂ , and FCON=SF₂ as a function of rotation about the N-S(IV) multiple bond showed that each total energy curve possessed a broad, flat minimum. Rotamers derived with only slight excitation would possess equal energy. Therefore, this multiple bond is nonrigid in contrast to the usual concept of the pπ-pπ double bond. The d-orbital contribution accounts for approximately 50% of the total π-bonding and is practically independent of the nature of the substituents on the nitrogen atom. Low temperature F-19 nmr studies showed that splittings occurred which can be explained on the basis of the total energy curves derived from the calculations. / Doctor of Philosophy
50

Factors related to the adoption of the consumer and homemaking curriculum by home economics teachers in Virginia secondary schools

Mays, Sue Bostic January 1975 (has links)
The purpose of this study was to identify and examine selected factors related to the adoption and implementation of curriculum change by home economics teachers in Virginia's public secondary schools. The major objective was to determine the relationship between the adoption of curriculum change and: (1) participation by home economics teachers in curriculum development activities and (2) selected demographic data. The population selected for the study were the consumer and homemaking teachers employed in Virginia's public secondary schools for 1973-1974. Stratified systematic sampling procedures were employed in which the teachers were divided into two subpopulations. The first subpopulation were teachers who participated directly in curriculum development activities. The second subpopulation were teachers not directly involved in curriculum development activities. A total of 180 teachers were included in the study; 161 responded for a response rate of 89 percent. The instrument (questionnaire) contained a list of fifty-one items. The three sections of the questionnaire included demographic data and participation and implementation inventories. A likert-type scale, ranging from one (strongly disagree) to six (strongly agree) was used to determine the strength of disagreement and agreement on the selected statements pertaining to participation in curriculum development and implementation of curriculum change. The responses were analyzed statistically by factor analysis, canonical correlations, bivariate correlation coefficients, tabulation and cross tabulations, and Pearson's correlation coefficients were computed to test the null hypotheses. Factor analysis of the responses resulted in the identification of three factors rotated for both the fourteen statements and the twenty-three statements. Canonical correlations and bivariate correlation coefficients were computed to determine if there was a significant relationship between the factor scores and each of the demographic variables. Pearson's product-moment correlation coefficients were computed to test the null hypotheses for significance. The findings indicated that there was no significant relationship between participation and adoption of curriculum change. A significant relationship was found between the age of the teacher, type of school, and manner in which the teachers received the Guide and teachers' adoption of curriculum change. No significant relationship was found between the level of educational preparation, area of undergraduate preparation, number of years experience, years in present system, source of school population, size of school enrollment, presence of a local supervisor of home economics education and adoption of curriculum change. Findings indicated a significant correlation between teachers who reported teaching in high school, teaching in rural communities, receiving the Guide at the annual Vocational Home Economics Teachers Conference, less number years of home economics teaching experience and participation perceived to be useful and essential to curriculum change and adoption. In view of the findings of this study, it is recommended that careful consideration should be given to the selection of teachers for participation in curriculum development activities and the manner in which curriculum materials are presented and disseminated to teachers. It is recommended that the Guide be re-evaluated as to its appropriateness for students in the middle, junior, and/or intermediate schools. It is further recommended that factors identified in this study which have a relationship to adoption and implementation of curriculum change should be considered in future curriculum development activities. / Ed. D.

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