9 resultados para Difference schemes

em Brock University, Canada


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All-electron partitioning of wave functions into products ^core^vai of core and valence parts in orbital space results in the loss of core-valence antisymmetry, uncorrelation of motion of core and valence electrons, and core-valence overlap. These effects are studied with the variational Monte Carlo method using appropriately designed wave functions for the first-row atoms and positive ions. It is shown that the loss of antisymmetry with respect to interchange of core and valence electrons is a dominant effect which increases rapidly through the row, while the effect of core-valence uncorrelation is generally smaller. Orthogonality of the core and valence parts partially substitutes the exclusion principle and is absolutely necessary for meaningful calculations with partitioned wave functions. Core-valence overlap may lead to nonsensical values of the total energy. It has been found that even relatively crude core-valence partitioned wave functions generally can estimate ionization potentials with better accuracy than that of the traditional, non-partitioned ones, provided that they achieve maximum separation (independence) of core and valence shells accompanied by high internal flexibility of ^core and Wvai- Our best core-valence partitioned wave function of that kind estimates the IP's with an accuracy comparable to the most accurate theoretical determinations in the literature.

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Existing research on attraction to body features has suggested that men show general preferences for women with lower waist-to-hip ratios (WHR), larger breasts, and slender body weights. The present study intended to expand on this research by investigating several individual difference factors and their potential contribution to variation in what men find attractive in female body features. Two hundred and seventy-three men were assessed for sex-role identity, 2D:4D digit ratios (a possible marker of prenatal exposure to androgens, and thus masculinization), physical attractiveness, early sexual experiences (as indices of early sexual conditioning), and early family attitudes toward body features, as well as their current preferences for WHR, breast size, weight, and height in women. For WHR, as predicted, physical attractiveness, early sexual experiences, and lower (more masculine) right-hand 2D:4D ratios significantly predicted current preferences for more feminine (lower) WHR. Early sexual experiences significantly predicted later preferences for breast size; in addition, more masculine occupational preferences and lower (more masculine) left-hand 2D:4D ratios predicted preferences for larger breasts. Participants' height, education level, Unmitigated Agency (masculinity) scores, and early sexual experiences significantly predicted current preferences for height. Finally, early sexual experiences significantly predicted current preferences for weight. The results suggest that variation in preferences for women's bodily features can be uniquely accounted for by a number of individual difference factors. Strengths and weaknesses of the study, along with implications for future research, are discussed.

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One hundred and five primarily Caucasian undergraduate couples were tested to study the phenomenon of attitude alignment, or the way in which individuals change their opinions to achieve greater attitudinal congruence with their romantic partners, and the hypotheses that relationship closeness, affect, attachment, social desirability, and centrality are each related to attitude alignment for individuals in close couples. The couples filled out an attitude questionnaire consisting of 50 issues in which they were asked to give their attitude on a scale from 1 to 9 as well as to rate the centrality, or importance, of that issue on a scale from 1 to 9. Before discussing four of these issues with each other - 2 were more central to the man and less central, or peripheral, to the woman, whereas the other 2 were central to the woman and peripheral to the man - the individuals completed established measures of relationship closeness, affect, attachment, and social desirability. The couples then filled out the identical attitudes questionnaire again, and their answers on the four discussion issues were compared to their prediscussion answers to determine whether attitude alignment had occurred. There were two experimental groups: a social desirability group, where the couples were told it was natural and normal to disagree with their partners, and a control group. Results indicated that attitude alignment did significantly occur across all couples, but most other variables - including centrality, relationship closeness, and affect - did not predict attitude alignment behaviour. As well, the social desirability experimental groups did not significantly differ on attitude alignment behaviours, but higher scores on the social desirability scale, specifically self-deception, significantly predicted higher attitude alignment scores across all couples. Large differences between individuals' frequency.

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This study explores how new university teachers develop a teaching identity. Despite the significance ofteaching, which usually comprises 40% of a Canadian academic's workload, few new professors have any formal preparation for that aspect of their role. Discipline-specific education for postsecondary professors is a well-defined path; graduates applying for faculty positions will have the terminal degree to attest to their knowledge and skill conducting research in the discipline. While teaching is usually given the same workload balance as research, it is not clear how professors create themselves as teaching professionals. Drawing on Kelly's (1955) personal construct theory and Kegan's (1982, 1994) model ofdevelopmental constructivism through differentiation and integration, this study used a phenomenographic framework~(Marton, 1986, 1994; Trigwell & Prosser, 1996) to investigate the question of how new faculty members construe their identity as university teachers. Further, my own role development as researcher was used as an additional lens through which to view the study results. The study focused particularly on the challenges and supports to teaching role development and outlines recommendations the participants made for supporting other newcomers. In addition, the variations and similarities in the results suggest a developmental model to conceptions ofteaching roles, one in which teaching, research, and service roles are viewed as more integrated over time. Developing a teacher identity was seen as a progression on a hierarchical model similar to Maslow's (1968) hierarchy of needs.

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Recent Ontario legislation by the Ministry of Education has targeted a goal of 50 percent as the minimum objective for representation by women in positions of responsibility by the year 2000. As a result,those few women currently in the field of Educational Administration have become a focus for researchers. The intent of this research is to contribute to the current knowledge and understanding of women principals in the leadership role. In-depth interviews with four experienced female principals were conducted centering on their perceptions and experiences on a wide range of issues that included: gender characteristics and impact on role, perceived differences as a result of gender characteristics, decision making, curriculum leadership, communication, the perception of others, and the advantages and disadvantages of being a woman in the role. Narrative profiles were constructed for each participant and analyzed. A description for each woman emerged by an analysis of common patterns and themes in the participants' narratives. Results revealed that the participants were able to identify and to describe particular gender traits that they perceived had impact on their role. Moreover the participants regarded their gender characteristics as facilitating and enhancing the performance of their role. Common patterns for all the participants emerged from the data that conveyed a strong feminine imagery of mother and espoused the idea of school as home, and staff and students as family. Leadership ii styles demonstrated an emphasis on collaborative decision making, open communication, and apparent difficulty and ambiguity arising from the role of Curriculum leader. The results of this study also indicate that personal metaphors ascribed and embedded in the narratives are significant in conceptualizing and interpreting the administrative role.

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Research and practice regarding LO students usually has focussed upon defining and supplementing deficiencies rather than seeking unique talents and capability patterns for learning and expression. This study examined nine dimensions that may constitute artistic or creative talent and compared LDs with "regular-class" students, pair-wise and as groups, for levels and distributions of the dimensions. For 14 LO and 9 "regular-class" elementary-school subjects, both genders, data were taken by direct observation, from a standardized test and assessments by two practicing artists. Assessments by artists were in concord. LOs improved more in "Composition". No other significant class, age or gender-related differences were found.

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We have presented a Green's function method for the calculation of the atomic mean square displacement (MSD) for an anharmonic Hamil toni an . This method effectively sums a whole class of anharmonic contributions to MSD in the perturbation expansion in the high temperature limit. Using this formalism we have calculated the MSD for a nearest neighbour fcc Lennard Jones solid. The results show an improvement over the lowest order perturbation theory results, the difference with Monte Carlo calculations at temperatures close to melting is reduced from 11% to 3%. We also calculated the MSD for the Alkali metals Nat K/ Cs where a sixth neighbour interaction potential derived from the pseudopotential theory was employed in the calculations. The MSD by this method increases by 2.5% to 3.5% over the respective perturbation theory results. The MSD was calculated for Aluminum where different pseudopotential functions and a phenomenological Morse potential were used. The results show that the pseudopotentials provide better agreement with experimental data than the Morse potential. An excellent agreement with experiment over the whole temperature range is achieved with the Harrison modified point-ion pseudopotential with Hubbard-Sham screening function. We have calculated the thermodynamic properties of solid Kr by minimizing the total energy consisting of static and vibrational components, employing different schemes: The quasiharmonic theory (QH), ).2 and).4 perturbation theory, all terms up to 0 ().4) of the improved self consistent phonon theory (ISC), the ring diagrams up to o ().4) (RING), the iteration scheme (ITER) derived from the Greens's function method and a scheme consisting of ITER plus the remaining contributions of 0 ().4) which are not included in ITER which we call E(FULL). We have calculated the lattice constant, the volume expansion, the isothermal and adiabatic bulk modulus, the specific heat at constant volume and at constant pressure, and the Gruneisen parameter from two different potential functions: Lennard-Jones and Aziz. The Aziz potential gives generally a better agreement with experimental data than the LJ potential for the QH, ).2, ).4 and E(FULL) schemes. When only a partial sum of the).4 diagrams is used in the calculations (e.g. RING and ISC) the LJ results are in better agreement with experiment. The iteration scheme brings a definitive improvement over the).2 PT for both potentials.

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This qualitative study explores practicing teachers' experiences of teaching in classrooms of diversity, that is, classrooms where students represent a variety of differences including race, culture, ethnicity, and class. More specifically, this study investigates the types of curricular and pedagogical practices teachers employ in their classrooms. This study attempts to make a contribution to the scholarship of critical pedagogy by drawing upon the works of critical pedagogues to make sense of participants' descriptions oftheir curricular and pedagogical practices. Four participants were involved in this study. Participants were elementary teachers in classrooms of difference in Ontario who contributed the primary sources of data by engaging in 2 individual interviews. Additional sources of data included a focus group meeting that 2 ofthe participants were able to attend, school board curriculum resource documents assisting teachers in teaching critically, as well as a research journal which the researcher kept throughout the study. The scholarship of critical pedagogy (Ellsworth, 1992; Giroux, 1993; McLaren, 1989) informs the analysis of participants' descriptions of their teaching experiences. Many of the participants did not engage in a practice of critical pedagogy. This study explores some of the challenges and possibilities of using critical pedagogy to create spaces in classrooms where teachers can build connections between the curriculum mandated by the government and the multiple identities and experiences that students bring into the classroom. This study concludes with a discussion on what teachers need to know to be able to begin creating equitable and educational experiences in classrooms of difference.

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Self-presentation reflects the processes by which individuals attempt to monitor and control the impressions others form of them (Schlenker & Leary, 1982). Concerns over impressions conveyed have been linked to numerous health behaviors (Crawford & Eklund, 1994; Martin, Leary, & O'Brien, 2001). The present study investigated the role of cognitive manifestations of dispositional and situational self presentational motivation (SPM) in 131 females with known groups differences on a measure of eating disorders. Participants were classified as in-treatment (IN = 39); at risk (AT = 46); and not at risk (NOT = 46) for eating disordered behaviour. Each participant completed The Brief Fear of Negative Evaluation Scale (FNE; Leary, 1983), the Public Self-Consciousness Scale (PSC; Fenigstein, Sheier, & Buss, 1975), and the Social Physique Anxiety Scale (SPA; Hart, Leary, & Rejeski, 1989), as measures of dispositional SPM. Situational SPM was assessed through Self-Presentational Efficacy (SPE; Gammage, Hall, & Martin, 2004), and the Exercise Motivation Inventory-2 (Markland & Ingeldew, 1997). Significant differences emerged on the measure of eating disorder behaviour between AT and NOT. To determine if group differences existed on measures of trait SPM an ANOVA was conducted. Results indicated that the NOT group experienced less FNE, PSC and SPA than the IN and AT groups, and the AT group experienced less FNE and PSC than the IN group. Pearson bivariate correlations were conducted on measures of trait SPM and EMI-2 subscales theoretically linked to SPM. It was found that FNE, PSC and SPA were all positively correlated with weight management for the NOT group. To determine if group differences existed on selfpresentational exercise motives independent samples I-tests were conducted. Results revealed that the AT group was more motivated to exercise for weight management, and appearance, and social recognition than the NOT group. To determine if group differences existed on the state measure of self-presentational efficacy a series of ANOVA's were conducted. Results revealed that the NOT group experienced significantly greater self-presentational efficacy expectancy and self-presentational outcome value than the AT group. Finally, a discriminant function analysis was conducted to determine if trait SPM would predict group membership. Results revealed that 63.4% of participants were correctly classified, with SPA, PSC, and FNE differentiating the NOT group from the AT and IN groups and FNE and PSC differentiating the AT group from the IN group. Thus self-presentation motivation appears to have an influence on females who have an eating disorder and those at risk for an eating disorder. Potential applications of the influence of self-presentational motives on eating disorders and future research directions are discussed.