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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.
61

The effects of relapse prevention training on smoking cessation

Burling, Thomas Arthur January 1981 (has links)
The major purpose of this study was to test the effectiveness of a relapse prevention program which was designed to help smokers anticipate and avoid relapse. To do this, twenty-three male and thirty-seven female smokers who volunteered for an experimental stop smoking clinic were randomly assigned to one of four treatments: (NF) a nicotine fading treatment in which smokers were required to gradually reduce the nicotine content of their brand prior to quitting; (ACS) an abbreviated American Cancer Society Stop Smoking Program; (NFACS) a treatment which combined the nicotine fading program with the American Cancer Society program; (NFRPT) a treatment which combined nicotine fading with a relapse prevention training program designed from the suggestions of Marlatt and Gordon (1978). A pre-test, post-test factorial design was used in which daily smoking rate, tar and nicotine levels, alveolar carbon monoxide levels, smoking topography measures, feelings of self-efficacy regarding quitting smoking, and attitude regarding health were assessed at baseline, end of treatment, 2-month follow-up, 3-month follow-up and 6-month follow-up. Contrary to expectations, the NFRPT group failed to exhibit superior outcome over controls on any dependent variable measuring smoking consumption. Further, the NFRPT group exhibited the poorest 6-month abstinence rate and had significantly higher 6-month daily smoking rates than the NF and ACS controls. As such, these findings fail to support the recent arguments of Marlatt and Gordon (1978) and others regarding the efficacy of relapse prevention training as a means of improving treatment outcome in smoking cessation programs. These results are also consistent with other recent studies which have failed to demonstrate the unique effectiveness of maintenance procedures. A secondary purpose of this study was to replicate the findings of Foxx and Brown (1979) and Prue, Krapfl, and Martin (1981) regarding the effectiveness of nicotine fading as an easy to administer, nonaversive smoking cessation treatment. As expected, the NF group exhibited significant decreases from baseline in daily cigarette rate and total nicotine intake at the 6-month follow-up. However, only moderate abstinence rates and carbon monoxide reductions were achieved. Compared to the data presented by Foxx and Brown (1979), the NF group of the present study achieved superior decreases in daily cigarette rate and tar and nicotine intake but poorer overall abstinence rates. Further, the present NF group did not exhibit superiority of the ACS control group. As such, these results are encouraging but only partially replicate the findings of Foxx and Brown (1979). / Ph. D.
62

On-line liquid distribution chromatographic/spectrofluorometric determination of PAH distribution in coal-derived products

Chen, Teng-Man January 1981 (has links)
On-line HPLC/Spectrofluorometric techniques have been applied to the determination of polycyclic aromatic hydrocarbons (PAHs) in coal-derived products. The PAHs were isolated by preparative silica gel columns with a hexane mobile phase, and fractionated into five samples based on the number of condensed rings. Each fraction was separated by reverse phase HPLC with an acetonitrile/water mobile phase. Compounds were detected by means of on-line fluorescence detection. Naphthalene, pyrene, fluoranthene, benzo(a)anthracene and benzo(a)pyrene were verified by comparing the excitation and emission spectra obtained by a stop-flow technique with those of PAH standards. A Picramido bonded phase packing was prepared by the reaction of picryl chloride and amino bonded phase silica gel, forming a charge-transfer active phase. The retention mechanism of aromatic hydrocarbons on the picramido bonded phase column was studied in three ways: electronic effects (Hammett cr function); temperature effects on heats of adsorption and solvent effects on capacity factors. Chromatographic properties of the picramido bonded phase column were compared to those of silica gel and amino bonded phase columns. An on-line LC/LC column switching system was developed for PAH analysis of solvent refined coal (SRC). It utilized a guard column, an amino bonded phase, and a picramido bonded phase column. The guard column prevented the highly polar materials from entering the analytical columns; the amino bonded phase column separated PAH materials into groups based on an adsorption mechanism; the picramido bonded phase column separated PAHs based on charge-transfer mechanism, and provided better resolution. / Ph. D.
63

Conodont biostratigraphy and paleoecology of the Lower Devonian Helderberg Group of Virginia

Cook, Elizabeth G. January 1981 (has links)
The occurrences of species of Delotaxis and Icriodus and the Ozarkodina remscheidensis eosteinhornensis--Ozarkodina remscheidensis remscheidensis lineage indicate that (1) most of the Keyser Formation of western Virginia is assignable to the uppermost Silurian eosteinhornensis zone; (2) the top of the upper limestone member of the Keyser is assignable to the basal Devonian woschmidti zone; (3) the remainder of the Helderberg Group is no younger than the delta zone; and (4) the basal Needmore Shale at the Price's Bluff section is assignable to the serotinus, patulus, or costatus costatus zones, of uppermost lower Devonian and lowermost Middle Devonian age, leaving a gap of at least six conodont zones represented by the Ridgeley Sandstone and its bounding unconformities. Conodonts tend to avoid tidal flat and lagoonal environments. They are not uniformly distributed through the rest of the section, but the occurrence of all but two species is not related to water depth, energy, or substrate; Ozarkodina excavata and Pseudooneotodus beckmanni prefer moderate energy environments. Icriodus helderbergensis and most of the simple cone species are associated with each other. There were 13,360 specimens collected, divided among 10 biological species and 15 form species; of the biological species, 3 are new and 2 are newly reconstructed apparatuses. / Master of Science
64

Planted architecture

Flanders, Michael Allen January 1981 (has links)
The creating of place will only occur in a response to its surrounding context. A built structure similar to a growing tree integral with its environment, inherently will Increase In complexity with age: as a result, living is encouraged. This work is merely a fundamental step in holding the belief of …. what is to be born, will be related to what is present. / Master of Architecture
65

Of the head and of the heart

Skreba, Leonard T. January 1981 (has links)
The work of an architect (his architecture) is a result of inspiration derived from his head and his heart. If his work is to be original, timeless, and improving, neither his head nor his heart must be fettered or coerced by any form of tyranny. The breaking of such bondage is necessary any time it is found to exist. It is with this spirit that design projects were approached and the architecture synthesized. Each project presented in this thesis, be it the house which is a celebration to man and to the sun, be it the satire with all its possible applications, be it one of several form projects, or be it the International House of Students designed to accommodate two hundred and fifty (250) students of multinational origin, reflect the dialogue between the architect's head and his heart. Collectively the projects represent a continuum of this dialogue. Only time can be the judge of the strength of an architect's head and of the purity of his heart. / Master of Architecture
66

An application of the hedonic approach to estimating prices for steam coal contract terms

Fletcher, Michael A. January 1981 (has links)
The hedonic approach involves determining the characteristics of a good or service that have a market price. Simultaneously, estimates of those prices are made using regression analysis. Both delivered and FOB mine prices are examined in regional U.S. markets. The steam coal contract terms examined include Btu, sulfur, and ash content; transportation cost, average annual tons delivered, start year of the contract, length of contract, buyer controlling interest in the mining operation, coal mine locations, and the individual buyers. Data for about eighty-five percent of all 1978 steam coal deliveries is utilized. The major findings were that coal price structure varies substantially across markets, from year to year, and for delivered prices and FOB mine prices. Btu is usually, but not always, the most important characteristic in explaining coal price variations. Length of contract is occasionally more important. Transportation cost and sulfur content are usually of high importance. Some buyers have a substantial impact on price because of market imperfections and poor buying practices. The regression results were robust. / Master of Arts
67

Étude de quelques propriétés anatomiques et physiques de provenances-descendances de peuplier deltoide (Populus deltoides bartr.)

Delucchi, Marco 05 April 2024 (has links)
Dans la présente étude, nous avons étudié les caractéristiques physiques et anatomiques du bois de peuplier deltoïde afin de pouvoir bâtir une sélection sur des données quantitatives en vue d'une amélioration de cette espèce. Le matériel, des carottes de 5,0 mm de diamètre prises à une hauteur de 0,4 m du sol, provenant du populetum de Villeroy (Québec), était âgé de dix ans. La densité basale, la longueur des fibres et l'analyse de tissu ont été choisies comme paramètres importants, soit pour approfondir les connaissances de cette espèce, soit pour effectuer une sélection efficace. Pour mieux comprendre l'interdépendance de ces paramètres, on les a reliés à des données auxométriques, tels le taux de croissance annuelle, la largeur du dernier cerne formé, la hauteur des arbres et la coloration ou pourriture du bois de coeur. La densité basale du peuplier deltoïde (353,4 kg/m³) se trouve être inférieure à celle du peuplier faux-tremble. Celui-ci étant en forêt naturelle le peuplier le plus utilisé au Québec, pourrait donc être partiellement substitué par le deltoïde en plantation. L'héritabilité au sens strict de ce caractère (97,33% à l'âge de huit ans) permet une sélection efficace des arbres ou familles intéressantes et garantit la stabilité des descendants pour ce paramètre. Une relation entre la densité basale et les conditions de croissance n'a pas pu être trouvée pour l'espèce en question. Ainsi, ce paramètre n'est ni fonction de la largeur des cernes ni fonction du taux de croissance annuelle, mais en relation directe avec l'épaisseur de la paroi secondaire des fibres. La longueur des fibres du peuplier deltoïde (0,956 mm) est légèrement inférieure à celle des autres espèces nord-américaines de peuplier. Il est cependant possible de l'augmenter en sélectionnant les arbres, dont la longueur se situe au-dessus de la moyenne, puisque ce caractère lui aussi est sous contrôle génétique. La longueur des fibres n'est pas fonction du taux de croissance radiale et n'a pas de relation avec les conditions de croissance. La longueur maximale étant atteinte à environ dix ans, ceci présume une montée très rapide pendant les premières années de croissance. L'espèce étudiée possède une surface moyenne occupée par les fibres de 66,53%. Ce paramètre est inversement proportionnel à la proportion de surface occupée par les vaisseaux. Il semble être influencé par les conditions de croissance, d'autant plus que la mise en place des vaisseaux est fonction de l'ampleur de la couronne de l'arbre. L'analyse des résultats nous a démontré que le pourcentage des fibres augmente avec la largeur du cerne. On peut donc conclure qu'en améliorant les conditions de croissance, on obtiendra automatiquement un pourcentage supérieur de fibres. Cette étude qui a été effectuée dans le but d'acquérir des connaissances sur la qualité du bois de peuplier deltoïde, met à la disposition du sélectionneur non seulement des données générales, mais aussi toute une série de corrélations, de régressions et de calculs d'héritabilité permettant une sélection efficace.
68

Factors influencing the educational aspirations of women pursuing a non-traditional career in law

Westbrook, Robert Charles January 1981 (has links)
The purpose of this study was twofold: (1) to identify variables that can be used to describe women pursuing nontraditional careers; and, (2) to determine the individuals who had the greatest influence on the educational aspirations of these women. A questionnaire, based on a review of the literature, was constructed to identify descriptive variables and factors influencing non-traditional educational aspirations. A self-administered survey was distributed to all women students at a southern law school. The completed questionnaire was returned by 123 women (41%). The data were analyzed using descriptive statistics and two-way joint frequency distributions. The major findings were: 1. Both parents were equally as influential on the respondents’ educational aspirations, despite a markedly higher educational level indicated for the father. 2. Sibl rank was not a contributing variable. 3. Mothers were not used as role models by the respondents. 4. Parents and significant-others were equally as likely to be seiected as the most influential person in determining the respondents' educational aspirations. As the way in which the role of women in our society is viewed changes, the ·variables influencing the educational aspirations of women will continue to change. Researchers must be. aware of these shifts and not be satisfied with identifying influential variables at a given point in time. / Master of Science
69

Non-punitive grading practices in the two-year college

Knight, William E. January 1981 (has links)
The status of non-punitive grading practices and policies in the two-year college remained highly uncertain due to a lack of substantive research. Therefore, the purpose of this study was to answer the following research questions: (1) How many public and private two-year colleges are currently using non-punitive grading practices? (2) What are the different forms of non-punitive grading practices now in use in public and private two-year colleges? (3) Are there differences in non-punitive grading practices among two-year colleges with different enrollment classification? (4) Are there differences in non-punitive grading practices among public and among private two-year colleges with different levels of academic policy control? (5) Are there differences in non-punitive grading practices among public and among private two-year colleges with different curricular emphasis? (6) What is the level of satisfaction among Deans of Instruction with the current non-punitive grading in public and private two-year colleges? (7) What are the future trends of non-punitive grading practices in public and private two-year colleges? The Non-Punitive Grading Practices Survey was designed to address the seven major research questions and was sent to 1,030 chief academic officers of public (n=866) and private (n=164} two-year colleges located in the continental United States. Seven hundred seventy-eight usable returns were received, representing a 75.5 percent response rate. The following conclusions were drawn from the findings: (1) Nonpunitive grading practices, in its purest forms, remain a viable grading system in a limited number of public and private two-year colleges during 1980-1981. (2) Non-punitive grading practices are considered to be "experimental" by many administrators and the majority of users of non-punitive grading do so on a limited basis. (3) Most academic deans in two-year colleges do not believe that non-punitive grading is consistent with the mission of their respective institutions. (4) An overwhelming majority of the deans in institutions with non-punitive grading practices favor non-punitive grades which represent the least change from traditional grading systems. (5) For non-punitive grading systems to be the exclusive methods of student evaluation academic policy control must be maintained at the local or state level. (6) University control over the academic policy of a two-year college is detrimental to the existence of non-punitive grading systems. (7) Curricular emphasis within pµblic community colleges has no apparent effect on the utilization of non-punitive grading practices. (8) Deans of instruction who utilize non-punitive grading practices, exclusively or experimentally, are very satisfied with these grading systems and practices. (9) No revolutionary changes in grading. systems are likely to occur in the next five years. (10) Non-punitive grading. systems will remain the minority grading systems in public two-year colleges.· (11) It is further concluded that faculty support is vital to the implementation and the deletion of non-punitive grading practices in two-year colleges. / Ed. D.
70

A construct validity study of the career development inventory and the attitude scale of the career maturity inventory

Dean, Susan A. January 1981 (has links)
The purpose of this study was to gain more information about the nomological network that supported the construct of career maturity. To achieve this purpose nine hypotheses were tested using a sample of 104 fourth year college students and 24 first year college students. These hypotheses tested the relationship of the within and between portions of the nomological network, the monotonic function of scores on measures of career maturity, and the sex differences of scores on measures of career maturity. A correlation matrix, a truncated multitrait-multimethod matrix, and t-tests between group means revealed that the convergent and discriminant validity of the construct of career maturity as measured by the Career Development Inventory and the Attitude Scale of the Career Maturity Inventory is far from assured. The Attitude Scale of the CMI failed to converge on the attitudinal scales of the CDI and correlated significantly with three out of the four cognitive scales of the CDI. The attitudinal scales of the CDI converged as expected. The cognitive scales of the CDI showed moderate correlations with each other with the exception of Scale 6, Information A and Preferred Occupation. Scale 6 had very low correlations with all of the CDI scales. Scales 1, 3, 4, and 5 of the CDI and the Attitude Scale of the CMI failed to present a pattern of correlations that would support their discriminant validity. Scale 1 of the CDI had significantly higher r's with locus of control and personal adjustment than with Scale 3 of the CDI. The Attitude Scale of the CMI had a significantly higher r-with grade point average than with Scales 2 and 6 of the CDI. It also had a significantly higher r with locus of control than with Scale 2 of the CDI. Scale 3 had a significantly higher r with grade point average than with Scales 1, 2 and 6 of the CDI. Scale 4 had a significantly higher r with grade point average than with Scales 2 and 6 of the CDI. Scale 5 had a significantly higher r with grade “l point average than with Scale 6 of the CDI. There were no significant differences between mean scores of female and male fourth year college 6 students at the .05 level on Scales 2, 3 and 5 of the CDI and the Attitude Scale of the CMI. Fourth year college students had significantly higher mean scores at the .05 level than first year college students on Scales 1 and 5 of the CDI. / Ed. D.

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