Current Search: Analysis (x)
Pages
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Title
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Dynamic response and stability of viscoelastic structures by interval mathematics.
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Creator
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Duan, Dehe., Florida Atlantic University, Elishakoff, Isaac
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Abstract/Description
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It is demonstrated in this thesis that the interval mathematics is a powerful tool to deal with uncertain phenomena especially when the uncertainty in bounded. In this thesis, we apply interval mathematics to several engineering problems, apparently for the first time in the world literature. The following topics are included: (1) The application of interval mathematics in several applied mechanics problems. A brief review of basis concepts is given, and some problems are presented to...
Show moreIt is demonstrated in this thesis that the interval mathematics is a powerful tool to deal with uncertain phenomena especially when the uncertainty in bounded. In this thesis, we apply interval mathematics to several engineering problems, apparently for the first time in the world literature. The following topics are included: (1) The application of interval mathematics in several applied mechanics problems. A brief review of basis concepts is given, and some problems are presented to illustrate the application of interval mathematics. (2) The stability and dynamic response of viscoelastic plate are studied. The effect of viscoelastic parameters on critical velocity is elucidated. (3) The application of Qiu-Chen-Elishakoff theorem in uncertain string and beam problems is investigated.
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Date Issued
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1994
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PURL
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http://purl.flvc.org/fcla/dt/15090
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Subject Headings
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Interval analysis (Mathematics), Viscoelasticity, Fractional calculus
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Format
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Document (PDF)
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Title
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Content analysis of design practices.
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Creator
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Shah, Prerak Pradyumna., Florida Atlantic University, Coulter, Neal S., College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
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Abstract/Description
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A database based on best manufacturing practices documents is explored relative to the "design" component of such best practices. This content analysis study yields lexical maps of key terms. Maps are categorized depending on their node arrangement in the following main groups: Cyclic maps, Sequential maps, Spoke-patterned maps and Isolated maps. A comparative study of names selected by different naming algorithms helps us in establishing the relation between map patterns and naming...
Show moreA database based on best manufacturing practices documents is explored relative to the "design" component of such best practices. This content analysis study yields lexical maps of key terms. Maps are categorized depending on their node arrangement in the following main groups: Cyclic maps, Sequential maps, Spoke-patterned maps and Isolated maps. A comparative study of names selected by different naming algorithms helps us in establishing the relation between map patterns and naming algorithms. Super network and distributions maps generated from the same database are useful in defining relations among the different maps. This study outlines the overall structure of design process through the maps' names and their interrelations.
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Date Issued
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1997
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PURL
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http://purl.flvc.org/fcla/dt/15420
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Subject Headings
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Content analysis (Communication), Production management--Databases
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Format
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Document (PDF)
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Title
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Image classification and image resolution issues for DOQQ analysis.
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Creator
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Boruff, Bryan Jeffery., Florida Atlantic University, Roberts, Charles
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Abstract/Description
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High-resolution imagery is becoming readily available to the public. Private firms and government organizations are using high-resolution images but are running into problems with storage space and processing time. High-resolution images are extremely large files, and have proven cumbersome to work with and control. By resampling fine resolution imagery to a lower resolution, storage and processing space can be dramatically reduced. Fine-resolution imagery is not needed to map most features...
Show moreHigh-resolution imagery is becoming readily available to the public. Private firms and government organizations are using high-resolution images but are running into problems with storage space and processing time. High-resolution images are extremely large files, and have proven cumbersome to work with and control. By resampling fine resolution imagery to a lower resolution, storage and processing space can be dramatically reduced. Fine-resolution imagery is not needed to map most features and resampled high-resolution imagery can be used as a replacement for low-resolution satellite imagery in some cases. The effects of resampling on the spectral quality of a high-resolution image can be demonstrated by answering the following questions: (1) Is the quality of spectral information on a color infrared DOQQ comparable to SPOT and TM Landsat satellite imagery for the purpose of digital image classification? (2) What is the appropriate resolution for mapping surface features using high-resolution imagery for spectral categories of information? (3) What is the appropriate resolution for mapping surface features using high-resolution imagery for land-use land-cover information?
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Date Issued
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2000
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PURL
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http://purl.flvc.org/fcla/dt/15787
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Subject Headings
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Remote sensing, Image processing, Image analysis
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Format
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Document (PDF)
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Title
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PROPAGATORS.
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Creator
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MESSITER, MARK A., Florida Atlantic University
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Abstract/Description
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This thesis discusses propagators and uses them to construct a solution to the following initial value problem under some special conditions: {du(t)/dt = A(t)u(t) u(s) = φ where A(t) is a linear operator in a Banach space X for every t ε R, φ ε X, and s ε R.
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Date Issued
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1981
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PURL
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http://purl.flvc.org/fcla/dt/14080
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Subject Headings
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Banach spaces, Hilbert space, Functional analysis
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Format
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Document (PDF)
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Title
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POLARIZED ELECTRONIC SPECTRA OF TRANS-DIACIDOBIS(ETHYLENEDIAMINE)CHROMIUM(III) COMPLEXES.
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Creator
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MILLER, NELSE CHRISTIAN, Florida Atlantic University
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Abstract/Description
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Polarized electronic spectra of trans-diacidobis (ethylenediamine )- chromium(III) complexes were measured at liquid nitrogen temperature, the diacido groups being aquochloro, aquobromo, bromochloro, bis(N, N-dimethylformamide), chloro(N, N-dimethyl£ormamide) and bromo(N, N-dimethylformamide). The quadrate components of the first two cubic bands were polarized and assigned on the basis of predicted polarization pattern for D4h vibronic mechanism for d^3 configuration. The higher energy...
Show morePolarized electronic spectra of trans-diacidobis (ethylenediamine )- chromium(III) complexes were measured at liquid nitrogen temperature, the diacido groups being aquochloro, aquobromo, bromochloro, bis(N, N-dimethylformamide), chloro(N, N-dimethyl£ormamide) and bromo(N, N-dimethylformamide). The quadrate components of the first two cubic bands were polarized and assigned on the basis of predicted polarization pattern for D4h vibronic mechanism for d^3 configuration. The higher energy intraconfigurational doublets were uncovered in most of the systems. The bis(N, N-dimethylformamide) complex showed two high-energy spin-forbidden bands at ~32,000 cm^-1 not previously observed in the spectra of chromium(III) complexes. The ligand field and electron correlation parameters were evaluated by fitting the observed band maxima with d^3 quadrate energy equations including full configuration interaction but neglecting spin-orbit perturbation. The parameters of these complexes and of the other trans-diacidobis (ethylenediamine) systems obtained by others were analysed in terms of the bonding nature of ligands.
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Date Issued
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1974
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PURL
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http://purl.flvc.org/fcla/dt/13639
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Subject Headings
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Spectrum analysis, Chromium--Spectra, Chemistry, Analytic
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Format
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Document (PDF)
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Title
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Photoluminescence analysis of zinc(1-x) manganese(x) selenium.
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Creator
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Xue, Jun, Florida Atlantic University, Medina, Fernando D.
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Abstract/Description
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Zn1-x is a ternary alloy belonging to a class of materials known as Diluted Magnetic Semiconductors (DMS's). Single-crystal samples of this material possesses a cubic (zinc-blende) structure for x 300 K. Three emission bands are detected and are named the YEL (centered ~2.12 eV), ORA (centered 1.91 --> 1.98 eV) and IR bands. The shift of the YEL band is observed and related to the d-d interaction of the Mn^+2 ions and to thermal lattice expansion. The electron-phonon interaction is used to...
Show moreZn1-x is a ternary alloy belonging to a class of materials known as Diluted Magnetic Semiconductors (DMS's). Single-crystal samples of this material possesses a cubic (zinc-blende) structure for x<0.30 and a hexagonal (wurtzite) structure for 0.30 300 K. Three emission bands are detected and are named the YEL (centered ~2.12 eV), ORA (centered 1.91 --> 1.98 eV) and IR bands. The shift of the YEL band is observed and related to the d-d interaction of the Mn^+2 ions and to thermal lattice expansion. The electron-phonon interaction is used to explain the broadening of the YEL band. A model is proposed to explain the existence of the ORA band and the shift of its energy with temperature and Mn concentration. This model for the first time provides a detailed explanation of the anomalous behavior of the energy gap of this material for low Mn concentrations.
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Date Issued
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1997
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PURL
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http://purl.flvc.org/fcla/dt/15388
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Subject Headings
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Diluted magnetic semiconductors--Analysis, Photoluminescence
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Format
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Document (PDF)
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Title
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Spectroscopic studies of zinc(1-x) manganese(x) sulfur.
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Creator
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Chen, Xiaoming., Florida Atlantic University, Medina, Fernando D.
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Abstract/Description
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The optical properties of the diluted magnetic semiconductor Zn1-x MnxS have been studied by using photoluminescence emission, lifetime and excitation spectroscopies. In photoluminescence spectroscopy three bands were found peaking at 585 nm (yellow band), 650 nm (orange band) and 750 nm (red band). For the yellow and red bands the peak position changes little with Mn concentration. For the orange band the peak energy decreases with increasing Mn concentration. The lifetimes of the yellow,...
Show moreThe optical properties of the diluted magnetic semiconductor Zn1-x MnxS have been studied by using photoluminescence emission, lifetime and excitation spectroscopies. In photoluminescence spectroscopy three bands were found peaking at 585 nm (yellow band), 650 nm (orange band) and 750 nm (red band). For the yellow and red bands the peak position changes little with Mn concentration. For the orange band the peak energy decreases with increasing Mn concentration. The lifetimes of the yellow, orange and red bands were found to be about 70, 50 and 7 mus. The results of the lifetime measurements support the assumption that there is energy transfer from the yellow to the red band through radiationless transitions. In the excitation spectroscopy of the yellow band four peaks were found peaking near 526, 487, 461 and 426 nm. These four bands have been ascribed to transitions from the four lowest excited states of Mn ++ to the ground state. (Abstract shortened with permission of author.)
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Date Issued
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1992
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PURL
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http://purl.flvc.org/fcla/dt/14790
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Subject Headings
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Diluted magnetic semiconductors, Photoluminescence, Spectrum analysis
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Format
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Document (PDF)
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Title
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THE TAXONOMIC AND NON-TAXONOMIC CLUSTERING AND RECALL OF YOUNG CHILDREN IN A SORTING AND DELAYED RECALL TASK.
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Creator
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ZAKEN, FLORA JANE, Florida Atlantic University
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Abstract/Description
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Several studies have found recall and clustering performance of young children to be greater with non-taxonomic (NT) than with taxonomic (T) materials, while other studies have found the reverse. The present experiment has tried to resolve this discrepancy by introducing the variable of criterion vs single sorting prior to recall. A comparison of Immediate and Delayed recall between child-generated T and child-generated NT categories under criterion (two consecutive identical sorts) and...
Show moreSeveral studies have found recall and clustering performance of young children to be greater with non-taxonomic (NT) than with taxonomic (T) materials, while other studies have found the reverse. The present experiment has tried to resolve this discrepancy by introducing the variable of criterion vs single sorting prior to recall. A comparison of Immediate and Delayed recall between child-generated T and child-generated NT categories under criterion (two consecutive identical sorts) and single sorting conditions was used to assess the differences in these T and NT grouping patterns as a basis for organizing recall. Although there were no significant interactions with delay, when subjects sorted only once, recall performance was greater with T related materials. However, when subjects sorted to a stable criterion of two consecutive identical sorts, recall performance with NT related materials was greater than performance with T related materials. These results suggest that under single sorting conditions, the use of T categories may have resulted in a better fit with the child's semantic memory structure than NT groupings. However, with stable sorting, both T and NT grouping patterns were equally consolidated into the memory structure, making them both equally retrievable.
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Date Issued
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1980
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PURL
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http://purl.flvc.org/fcla/dt/14009
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Subject Headings
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Memory in children, Cluster analysis, Recollection (Psychology)
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Format
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Document (PDF)
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Title
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A METHOD OF ANALYSIS FOR EVALUATING THE EFFECTIVENESS OF PARTIAL DAMPING LAYER TREATMENTS FOR CIRCULAR PLATES.
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Creator
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SHOMSTEIN, SAMUEL COLEMAN., Florida Atlantic University, Stevens, Karl K., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
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Abstract/Description
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This thesis develops an approach for predicting the loss factors and natural frequencies of circular plates with partial and complete viscoelastic damping surface treatments. Plates with fixed and simply supported edges were considered. The analysis is based on an energy approach to the free vibration of plates. Results predicted were compared with those obtained experimentally by Lopes. Both the experimental and analytical studies clearly indicate that substantial amounts of material and...
Show moreThis thesis develops an approach for predicting the loss factors and natural frequencies of circular plates with partial and complete viscoelastic damping surface treatments. Plates with fixed and simply supported edges were considered. The analysis is based on an energy approach to the free vibration of plates. Results predicted were compared with those obtained experimentally by Lopes. Both the experimental and analytical studies clearly indicate that substantial amounts of material and added weight can be saved by using partial damping surface treatments.
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Date Issued
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1985
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PURL
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http://purl.flvc.org/fcla/dt/14279
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Subject Headings
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Damping (Mechanics)--Analysis, Viscoelasticity--Experiments
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Format
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Document (PDF)
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Title
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AN AWARENESS MODEL OF INTERPERSONAL BEHAVIOR IN EDUCATIONAL LEADERSHIP TRAINING.
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Creator
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BATTS, LESLIE DAVIS, Florida Atlantic University, Logsdon, James D.
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Abstract/Description
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The problem of this study was threefold: (1) To explore the availability of instruments that will increase student awarenesses on interpersonal and intrapersonal behavior. (2) To design or modify an instrument to be used as part of an awareness model in educational leadership training. (3) To survey awareness changes in a sample of the student population when the model is used in educational leadership training. A pilot study was conducted on a group of students enrolled in a Middle School...
Show moreThe problem of this study was threefold: (1) To explore the availability of instruments that will increase student awarenesses on interpersonal and intrapersonal behavior. (2) To design or modify an instrument to be used as part of an awareness model in educational leadership training. (3) To survey awareness changes in a sample of the student population when the model is used in educational leadership training. A pilot study was conducted on a group of students enrolled in a Middle School Leadership Sequence during the summer of 1973. This initial effort resulted in several training instruments, among them the Personnel Relations Survey, that were effective in the area of behavioral awareness. Of the instruments used in the pilot study, The Personnel Relations Survey was selected and modified for use in educational leadership training. Since the survey was designed to be used originally by manager trainees in an industrial setting, the nonsignificant modification was, for the most part, the substitution of educational personnel for employees, managers, and supervisors. The survey instrument which was a part of the model was used with a sample of students in an experimental and a control group to measure the dependent variables of exposure and feedback in relationships with teachers, principals, and superintendents. The participant was provided with a graphic analysis of his interaction and awareness by using the Johari Window that was a part of the model. Results were treated statistically with multivariate analysis of variance. Of the three hypotheses treated, there was insufficient evidence to reject the two following: 1. There is no significant difference between the experimental and control treatment effect when one is considering the dependent measures of exposure and feedback relevant to feelings. 2. There is no significant difference among the interaction effect of treatment with personnel when one is con~idering the dependent measures of exposure and feedback relative to feelings. No significant difference was noted in the treatment main effect when comparing the performance of the experimental and control groups on the dependent measures. The interaction effect of treatment, personnel, and treatment with personnel was nonsignificant. was: One hypothesis that was rejected at the .05 level of significance There is no significant difference between the personnel relationships main effect when one is considering the dependent measures of exposure and feedback relevant to feelings. A significant difference in the main effect of personnel was investigated with a multiple comparison test and the results showed that relationships with superintendents were significantly different from the relationships with the two other groups of educational personnel when considering the dependent measure of exposure. The model was not designed to produce change but to produce an awareness of one's interaction style and more desirable styles to which the participant could change if he so desired. Recommendations were made for more effective use of awareness training in educational leadership.
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Date Issued
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1974
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PURL
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http://purl.flvc.org/fcla/dt/11632
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Subject Headings
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Interaction analysis in education, Interpersonal relations
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Format
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Document (PDF)
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Title
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The microprocessor design team assignment problem with a new multistage stochastic/Brownian motion model.
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Creator
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O'Grady, Thomas James., Florida Atlantic University, Han, Chingping (Jim), College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
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Abstract/Description
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The Microprocessor Design Team Assignment Problem models the microprocessor design efforts of Intel Corporation over a 29-year period from 1972 until 2001. The basic model is a Erlang queuing system based probability model of the individual programming-design team daily operations. After extensive research the Erlang Loss/Delay Blocked Multiserver Model is utilized throughout the dissertation The Erlang loss-delay model takes into account the Key Man Constraint for team leaders and...
Show moreThe Microprocessor Design Team Assignment Problem models the microprocessor design efforts of Intel Corporation over a 29-year period from 1972 until 2001. The basic model is a Erlang queuing system based probability model of the individual programming-design team daily operations. After extensive research the Erlang Loss/Delay Blocked Multiserver Model is utilized throughout the dissertation The Erlang loss-delay model takes into account the Key Man Constraint for team leaders and programming team personnel. The Microprocessor Design Team Assignment Problem Case Study and massive research effort, into Intel Corporations design efforts, is complicated by modeling a major programming-design team operation without any current data or assistance from Intel Corporation. However much of the lack of assistance and data was obtained by utilizing a critical managerial design team decomposition which answered most major questions about Intels lack of adequate personnel and overutilization of team leaders and asst. team leaders throughout the 48 months of most major design projects. The study-dissertation concludes that Intels and Hewlett Packards current positions in the computer industry are relatively secure because of extremely high entry level costs exceeding $850,000,000.00 million dollars. Many individual issues about programming-design team operations are analyzed in a great amount of detail. This is the first time that much of this design-programming team material and information is being made public for future research and continuing improvement upon large scale project managerial methods and techniques. The basic design-programming team effort is also modeled with Erlang probability models and stochastic Riccati differential equations. This modeling effort is discussed in great detail in chapter 5 and Appendix Alpha. It is believed that this fundamental research leads the way for more advanced efforts in manufacturing systems and possibly mechatronics for further models utilizing strong Markov properties. This research effort substantially advances the basic research and knowledge of Partially Observable Markov Decision Processes and Strong Brownian Motion with the basic unit being strong Markov properties.
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Date Issued
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2001
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PURL
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http://purl.flvc.org/fcla/dt/11962
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Subject Headings
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Brownian motion processes, Stochastic analysis, Microprocessors
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Format
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Document (PDF)
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Title
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A stability study of octadecylalumina columns for use in HPLC.
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Creator
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Goldberg, James Vincent, Florida Atlantic University, Haky, Jerome E.
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Abstract/Description
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Chromatographic stability studies of an alumina-based reversed phase, ODA, stationary phase were performed. These studies involved monitoring the chromatographic performance of columns packed with the ODA phase after separate, continuous treatment with aqueous solutions of trifluoroacetic acid and sodium hydroxide over a period of several weeks. Chromatographic performance of the ODA columns undergoing treatment with these mobile phases was evaluated by comparing changes in chromatographic...
Show moreChromatographic stability studies of an alumina-based reversed phase, ODA, stationary phase were performed. These studies involved monitoring the chromatographic performance of columns packed with the ODA phase after separate, continuous treatment with aqueous solutions of trifluoroacetic acid and sodium hydroxide over a period of several weeks. Chromatographic performance of the ODA columns undergoing treatment with these mobile phases was evaluated by comparing changes in chromatographic capacity factors, resolutions, plate numbers, and peak asymmetries of a test mixture consisting of uracil, phenol, aniline, methyl benzoate, m-toluidine, N,N-dimethylaniline, and toluene. The results indicate that the alumina-based ODA phase is stable under acidic conditions (pH 2--3) and exceptionally stable to chemical degradation under alkaline conditions (pH ∼ 11).
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Date Issued
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2000
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PURL
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http://purl.flvc.org/fcla/dt/12681
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Subject Headings
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Chromatographic analysis, High performance liquid chromatography
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Format
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Document (PDF)
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Title
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The role of asset reliability and auditor quality in equity valuation.
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Creator
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Fallatah, Yaser., Florida Atlantic University, Higgs, Julia
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Abstract/Description
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This paper brings together the auditor quality, asset reliability and firm valuation literatures by examining the role of auditor quality in equity valuation. The study broadly follows the Richardson et al. (2005) categorization of the reliability of accounting accruals of balance sheet components and conjectures that the role of auditor quality in equity valuation is more pronounced when asset reliability is not high. Auditor quality is measured using reputation, industry specialist and...
Show moreThis paper brings together the auditor quality, asset reliability and firm valuation literatures by examining the role of auditor quality in equity valuation. The study broadly follows the Richardson et al. (2005) categorization of the reliability of accounting accruals of balance sheet components and conjectures that the role of auditor quality in equity valuation is more pronounced when asset reliability is not high. Auditor quality is measured using reputation, industry specialist and tenure metrics. The underlying assumption is that auditor quality enhances the market's perception of firm value; as such, auditor quality may mitigate the cost of security mispricing documented by Richardson et al. (2005) for low or medium reliability accruals. The results of the study provide some support that high quality auditors contribute to the valuation of equity for assets. It is less clear as to whether the value is more pronounced for low or medium reliability assets.
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Date Issued
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2006
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PURL
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http://purl.flvc.org/fcla/dt/12231
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Subject Headings
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Auditing--Quality control, Econometrics, Investment analysis
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Format
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Document (PDF)
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Title
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A volume scattering model for sediment classification through acoustic means.
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Creator
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Jenkins, Michael Gerard., Florida Atlantic University, LeBlanc, Lester R.
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Abstract/Description
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A simple model is developed to evaluate the acoustic scattering environment of sediments based on the envelope function of digital sub-bottom sonar data. Scattering pressure and intensity histograms are produced from model results. These histograms are compared to the theoretical distributions expected for scattering event pressure and intensity. Sediment composition is inferred from the determined acoustic scattering environment. The model has been applied to X-Star digital sub-bottom data...
Show moreA simple model is developed to evaluate the acoustic scattering environment of sediments based on the envelope function of digital sub-bottom sonar data. Scattering pressure and intensity histograms are produced from model results. These histograms are compared to the theoretical distributions expected for scattering event pressure and intensity. Sediment composition is inferred from the determined acoustic scattering environment. The model has been applied to X-Star digital sub-bottom data taken in the vicinity of St. John's Harbor, New Brunswick. Model results are compared to ground truth (Borehole logs) taken within the survey area. This comparison indicates general trends within the sediment scattering environment which may be linked to sediment composition. Distinct differences in model results were noted over areas of differing sediment types.
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Date Issued
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1993
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PURL
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http://purl.flvc.org/fcla/dt/14945
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Subject Headings
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Sedimentation analysis, Underwater acoustics, Sound--Reverberation
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Format
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Document (PDF)
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Title
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Employment of modern analytical methods for adsorption studies and pharmaceutical analysis.
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Creator
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Foss, Wendy Marie, Florida Atlantic University, Haky, Jerome E.
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Abstract/Description
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Ultraviolet spectrophotometry was employed to investigate the adsorption of phenylphosphonic acid onto the surface of alumina from aqueous solution. It was found that an initial chemisorption occurred with monolayer coverage, reaching a maximum at a solution pH of 3.0. The results were interpreted as indicating that this and related adsorptions are controlled by ligand exchange processes involving electrostatic attraction between oppositely-charged species. In a separate project, high...
Show moreUltraviolet spectrophotometry was employed to investigate the adsorption of phenylphosphonic acid onto the surface of alumina from aqueous solution. It was found that an initial chemisorption occurred with monolayer coverage, reaching a maximum at a solution pH of 3.0. The results were interpreted as indicating that this and related adsorptions are controlled by ligand exchange processes involving electrostatic attraction between oppositely-charged species. In a separate project, high performance liquid chromatography was employed for the quantitative analysis of aminophylline in commercial thigh cream formulations. The analysis required derivatization of the compound by dansylation under carefully-controlled conditions. This enhanced its detection and separation from other cream components.
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Date Issued
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1997
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PURL
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http://purl.flvc.org/fcla/dt/15404
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Subject Headings
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Adsorption, Spectrophotometry, Chromatographic analysis, Solution (Chemistry)
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Format
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Document (PDF)
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Title
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Electrochemical behavior of carbon fiber cathode materials in organic electrolytes containing various lithium salts.
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Creator
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Durand, Severine Nathalie., Florida Atlantic University, Lipka, Stephen M.
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Abstract/Description
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The intercalation of anions into carbon fiber from organic electrolytes containing lithium salts was studied. The reversible intercalation of anions into carbon could lead to the possible substitution of conventional metal oxide cathode materials in lithium-ion cells. EWC300 was selected as the most suitable carbon fiber material based on data from preliminary tests. Experiments were performed with LiClO4 in EC/DMC and LiPF6 in EC/DMC electrolytes. Slow scan cyclic voltammetry (0.1 mV/s) and...
Show moreThe intercalation of anions into carbon fiber from organic electrolytes containing lithium salts was studied. The reversible intercalation of anions into carbon could lead to the possible substitution of conventional metal oxide cathode materials in lithium-ion cells. EWC300 was selected as the most suitable carbon fiber material based on data from preliminary tests. Experiments were performed with LiClO4 in EC/DMC and LiPF6 in EC/DMC electrolytes. Slow scan cyclic voltammetry (0.1 mV/s) and galvanostatic charge/discharge experiments at various C rates were used. Intercalation of PF6- occurred by staging and was highly dependent on the current density. High current density (20 mA/g) was necessary to reach potentials over 5 V vs Li to achieve intercalation capacities over 80 mAh/g. Powder x-ray diffraction revealed that carbon fibers became less crystalline after anions were intercalated into their structure. Scanning electron microscopy showed longitudinal cracking on the carbon fibers after 120 cycles indicating dimensional instability.
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Date Issued
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1999
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PURL
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http://purl.flvc.org/fcla/dt/15624
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Subject Headings
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Anions, Carbon fibers, Lithium cells, Electrochemical analysis
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Format
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Document (PDF)
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Title
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Essays on Actively Managed Mutual Funds.
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Creator
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Kaushik, Abhay, Barnhart, Scott W., Florida Atlantic University
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Abstract/Description
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In this dissertation, I examine three main issues in mutual fund research: 1) the performance of "sector funds" over the business cycles; 2) the performance and managerial characteristics of "focus funds" and finally 3) the impact of taxes and tax overhang on flow of funds & performance of "corporate bond funds". My first essay analyzes the performance of sector funds across different stages of business cycles. Using a sample of 1,488 sector funds over the period 1990 to 2005, I demonstrate...
Show moreIn this dissertation, I examine three main issues in mutual fund research: 1) the performance of "sector funds" over the business cycles; 2) the performance and managerial characteristics of "focus funds" and finally 3) the impact of taxes and tax overhang on flow of funds & performance of "corporate bond funds". My first essay analyzes the performance of sector funds across different stages of business cycles. Using a sample of 1,488 sector funds over the period 1990 to 2005, I demonstrate that sector funds perform differently across different stages in the business cycles. Average difference between expansion and recession cycles ranges from 2.75 percent per year to 3.78 percent per year. Findings of this essay further suggest that sector funds do exhibit different timing effects across recessions and expansions. Flow of funds and buy turnover ratio have differential effects across business cycles whereas sell turnover trading activities have a negative effect on funds' overall performance. My second essay analyzes the performance of "focus funds". These funds are well managed but tend to keep 50 or less stocks in their portfolio. Using a sample of 926 focus funds that existed during all or part of the period 1997 to 2006, I find that on average focus funds do not outperform a corresponding passive benchmark. My results further indicate that focus funds that are more concentrated in their top holdings, have larger net asset size, relatively young management and lower turnover ratios may offer higher abnormal returns compared to passive benchmarks. The third essay analyzes the effect of taxes and tax overhang on the flow of funds and performance in bond funds. Using a sample of 741 corporate bond funds that existed at some time during the period 1997 to 2006, findings of this essay indicate that new investors to bond funds are sensitive to unrealized capital gains/losses, however, the flow of funds is not affected by past dividend distributions. Findings further indicate that tax liabilities, unrealized gains/losses, and managerial tenure explain post-tax abnormal performance after controlling for investment style, and other known factors that explain the pre-tax performance ofbond funds.
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Date Issued
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2007
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PURL
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http://purl.flvc.org/fau/fd/FA00000307
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Subject Headings
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Mutual funds--Management, Investment analysis
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Format
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Document (PDF)
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Title
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Investigation of perfluoroalkyl bonded alumina-based stationary phases for reversed phase high performance liquid chromatography applications.
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Creator
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Mannschreck, Tina Marie, Florida Atlantic University, Haky, Jerome E.
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Abstract/Description
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The general chromatographic properties of perfluoroalkyl-bonded alumina-based stationary phases were evaluated by comparing hydrophobicities and selectivities to octadecyl-bonded silica phases. Potential applications for the perfluoroalkyl-bonded alumina-based stationary phases were also investigated by analyzing octapeptide mixtures as well as separations which employed totally aqueous mobile phases. The fluorinated alumina-based stationary phases investigated in this study were found to...
Show moreThe general chromatographic properties of perfluoroalkyl-bonded alumina-based stationary phases were evaluated by comparing hydrophobicities and selectivities to octadecyl-bonded silica phases. Potential applications for the perfluoroalkyl-bonded alumina-based stationary phases were also investigated by analyzing octapeptide mixtures as well as separations which employed totally aqueous mobile phases. The fluorinated alumina-based stationary phases investigated in this study were found to possess different chromatographic properties compared to octadecylsilica columns.
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Date Issued
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1994
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PURL
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http://purl.flvc.org/fcla/dt/15055
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Subject Headings
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Chromatographic analysis, High performance liquid chromatography
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Format
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Document (PDF)
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Title
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THE SPECIFIC ACOUSTIC IMPEDANCE OF FERROMANGANESE NODULES AT EIGHT KILOHERTZ.
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Creator
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GARDNER, DAVID LEE, Florida Atlantic University, Davidson, J. Blaine
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Abstract/Description
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Ferromanganese nodules are small, irregular lumps of precipitated metal oxides composed primarily of manganese, iron, copper, cobalt, and nickel which accrete in deep ocean environments. The nodules have mining value and commercial recovery is expected in the near future. As present techniques for the detection and evaluation of ferromanganese nodule deposits are cumbersome and time consuming, an investigation of the specific acoustic impedance of the nodules is conducted in an effort to...
Show moreFerromanganese nodules are small, irregular lumps of precipitated metal oxides composed primarily of manganese, iron, copper, cobalt, and nickel which accrete in deep ocean environments. The nodules have mining value and commercial recovery is expected in the near future. As present techniques for the detection and evaluation of ferromanganese nodule deposits are cumbersome and time consuming, an investigation of the specific acoustic impedance of the nodules is conducted in an effort to determine the feasibility of surveying ferromanganese nodule deposits via side-scan sonar techniques. An acoustic transmission line (impedance tube) is utilized to investigate the specific acoustic impedance of the ferromanganese nodule samples. The accuracy of the experimental technique is evaluated using a steel reference cylinder. Results of the tests (on the ferromanganese samples) indicate that the specific acoustic impedance of a typical ferromanganese nodule sample is 2.07 +- .15 x 106 Rayls. Suggestions for future investigations are also presented.
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Date Issued
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1976
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PURL
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http://purl.flvc.org/fcla/dt/13822
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Subject Headings
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Ferromanganese--Analysis, Acoustic impedance--Instruments
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Format
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Document (PDF)
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Title
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SPECTROSCOPIC MEASUREMENTS OF OH ABUNDANCES IN THE TERRESTRIAL ATMOSPHERE.
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Creator
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LANGSTON, JAMES HUTTON, II., Florida Atlantic University, Burnett, Clyde R., Charles E. Schmidt College of Science, Department of Physics
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Abstract/Description
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Spectroscopic observations were made of the resonance absorption of sunlight by the atmospheric hydroxyl radical (OH). The abundance of 0 terrestrial OH was measured from the Fritz Peak Observatory (39.92 N, 105.50°W) in Colorado during September of 1978. These measurements were made on the absorption of the P1 (1) line of the A^2sigma^+ - x^2pi(O , O) rotational band of OH at 3081.7 A. The instrument used was the PEPSIOS (Poly Etalon Pressure Scanned Interferometric Optical Spectrometer)...
Show moreSpectroscopic observations were made of the resonance absorption of sunlight by the atmospheric hydroxyl radical (OH). The abundance of 0 terrestrial OH was measured from the Fritz Peak Observatory (39.92 N, 105.50°W) in Colorado during September of 1978. These measurements were made on the absorption of the P1 (1) line of the A^2sigma^+ - x^2pi(O , O) rotational band of OH at 3081.7 A. The instrument used was the PEPSIOS (Poly Etalon Pressure Scanned Interferometric Optical Spectrometer) because of its high luminosity - resolution product . The computer methods ·~sed in the analysis procedure are described . These measurements indicated an average daytime vertical column abundance of (5.40 ± 0.67) x 10^13 OH molecules/cm^2.
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Date Issued
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1979
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PURL
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http://purl.flvc.org/fcla/dt/13968
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Subject Headings
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Spectrum analysis, Absorption spectra, Atmospheric chemistry
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Format
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Document (PDF)
Pages