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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.

The effects of complex additives and growth regulators on the growth and clonal propagation of Phalaenopsis orchids

Ackerman, Rodney Rex January 1988 (has links)
The goal of this study was two fold, the first was to determine the effect of different basal medium formulationsand medium supplements (complex additives and growth hormones) on the development and growth rate of Phalaenopsis orchids, while the second goal was to find or develop an efficent method for the clonal propagation of Phalaenopsis orchids.MethodsThe first part of this study was further subdivided in to several phases; the first of these involved a comparative study of the germination of Phalaenopsis ovules on six different basal medium formulations and seven different sets of medium supplements. The second phase involved a comparative study of the development of Phalaenopsis protocorms on six different basal medium formulations and ninteen different sets of medium supplements. The third phase involved a comparative study of the growth of Phalaenopsis seedlings on six different basal medium formulations and twelve sets of medium supplements. The forth and final phase involved a comparative study of the development and growth of Phalaenopsis protocorms and seedlings on media containing varing concentrations and combinations of auxins and cytokinins. The second part of this study involved a comparative study designed-to determine the suitability of several sizes of axillary buds and plantlets for the clonal propagation of Phalaenopsis orchids and the modification of several procedures in an attempt to determine suitable explant material and procedures for the commercial clonal propagation of Phalaenopsis orchids.Results and DiscussionResults of this study indicated that of the basal medium formulations and medium supplements tested Modified Heller's salt base medium and to a lesser extent Modified Vacin and Went salt base medium supplemented with vitamin formulation 1 and Bactopeptone yielded the highest percent germination and development up to the seedling stage. At the seedling stage the growth rate of seedlings grown on media supplemented with banana homogenate nearly doubled the growth rate of the seedlings grown on all of the other medium supplementstested.Results of the second part of this study indicated that by modifying the procedures of Bouriquet, Broly, and Legrand (1982) the proliferation rate (shoots per plantlet) could be increased by a factor of two to eight. This can be translated into an increase from two to five shoots per plantlet per six weeks to an increase of eight shoots per plantlet per six weeks with a minimal mortality rate. With further modification of the procedure of Bouriquet, Broly, and Legrand (1982), other results indicated that it may be possible to increase to forty the number of shoots per plantlet produced per six week period. / Department of Biology

The analysis and design of TLM mesh configurations for modelling electromagnetics

Raynes, Deborah Louise January 1999 (has links)
No description available.

The propagation of the Pacific Coast evergreen huckleberry, Vaccinium ovatum Pursh

Williamson, Henry Charles 15 May 1932 (has links)
Graduation date: 1932

Modélisation et étude de la transmission d'information par codes graphiques / Modelling and Study of Information Transmission with Graphical Codes

Houni, Karim 07 February 2008 (has links)
ALes codes graphiques tels que les codes-barres et les codes 2D sont une technologie majeure de l'identification et de l'EDI. L'affichage et la lecture de ces pictogrammes bicolores constituent un système singulier de communication numérique, ce qui nous a amené à conduire son analyse en nous axant sur la théorie de l'information. Nous avons proposé sur les bases radiométriques et optiques une modélisation du canal de transmission par un filtre linéaire bruité par un processus additif gaussien. Les paramètres du modèle sont ainsi fonction des caractéristiques du code, de son positionnement, de la puissance de rayonnement et des caractéristiques de la caméra. Les performances du système sont évaluées en calculant l'information mutuelle moyenne (IMM). Dans le cas 1D (codes-barres), l'IMM est estimée par une variante de l'étape "Forward" du BCJR en utilisant la markovianité du canal. L'IMM est alors une mesure objective à partir de laquelle nous définissons une profondeur de champ ainsi qu'une résolution spatiale théorique. Ces deux critères complètent et enrichissent leur pendant géométrique en tenant compte des distorsions et du bruit du canal. Dans le cas 2D, nous avons montré que le modèle implique que la distribution de probabilité des données émises sachant les observations (a posteriori) est celle d'un champ de Gibbs. Nous avons ainsi mis en évidence le lien entre l'estimation du flux d'information du système et celle de l'énergie libre du champ aléatoire. Parmi les perspectives des travaux: l'ajout de la couleur, l'application d'un codage canal et des principes turbo. / Graphical Codes such as barcodes and 2D codes are a leading technology in identification and EDI. Displaying and reading these black and white pictograrns is equivalent to a singular digital communication system such that we drove our study according to information theory. From radiometry and optics principles, we've proposed a transmission channel model as a linear filter with Gaussian noise. Model parameters are thus function of code and camera characteristics, positioning and radiating power. System performances are evaluated with the computation of average mutual information (AMI). ln the 1D case (barcodes), AMI is estimated with a version of the BCJR Forward recursion by using channel markovianity. AMI is then an objective measure from which we define a theoretic depth of field and spatial resolution. These two criteria complement their geometrical equivalent by considering channel distortions and noise. ln the 2D case, we've shown that the model imply that the probability distribution of data knowing observations (a posteriori) is a Gibbs random field. We have thus highlighted that the evaluation of system's information rate is equivalent to the estimation of the random field free energy. The perspectives of the works are: adding colour to the codes, channel coding and the application of turbo principles.

Winning the Catholic Reformation through the Conversion of Female Protestants: The Education of Les Nouvelles Catholiques in Seventeenth-Century France

Kang, Julie H. January 2010 (has links)
This dissertation examines the gendering of heresy and general ignorance in relation to the making of a centralized state in Catholic Reformation France. It studies the strategies of reformers and propagandists in France during the seventeenth century, whose main ambition was to extirpate heresy, namely, the religion of the French Reformed Church. In so doing, they targeted female Protestants in their efforts to establish a French state unified under the single religion of Catholicism. Established in Paris in 1632, the Propagation de la foi (Propagation of Faith) began to spread out to other regions of France in the mid-seventeenth century. Until the revocation of the Edict of Nantes in 1685, the deliberation records of the meetings of the provincial compagnies reveal an intense focus to convert Huguenot girls and women. Taking into account the significance of the early modern family in the making of a moral society, the Propagation’s plan to find new homes, often in the way of marriage, resonated with their ultimate objective and that of the French Catholic Reformation. Financial incentives drew in new female converts and at the same time allowed individual women and the families of girls to take advantage of the Propagation. In addition, religious reformers who denigrated the early modern female body created a binary comparison such that pious women could take part in French Catholicism’s war against Protestantism. Female missionaries, patrons, and maternal models defined, in opposition to idolaters and heretics, idealized aspects of femininity. Through a good upbringing or “education,” France was poised to become the kind of state that zealous Catholics envisioned. Early modern writers such as Fénelon could not emphasize enough a proper education for girls, whose primary teachers were their mothers. Parents and especially mothers, therefore, had the civic responsibility to raise their daughters well: to be modest and chaste. By reforming the family, reformers sought to make good Catholic daughters who would curtail the development of future generations of unruly Huguenot girls and women.

Cranberry nutrients, phenology, and nitrogen-phosphorus-potassium

DeMoranville, Carolyn J 01 January 1992 (has links)
The objective of this study was to compile and interpret nutritional and developmental data for cranberry (Vaccinium macrocarpon Ait.) as the basis for standardizing experimental techniques (particularly data collection) and tissue analysis, including tissue to sample, time of sampling, and normal element concentrations for 'Early Black'. Seasonal nutrient levels were determined in tissues of 'Early Black' cranberry under 10N-8.7P-8.3K fertilization (O, 170, 335, and 505 kg/ha). After three years, N, P, and K concentrations in new shoot tissues were positively affected by N-P-K supply. The N-P-K supply had no effect on Ca and Mg concentrations in new shoot tissue but B concentrations were lowest in unfertilized plants. N, P, K, and Cu concentrations in new shoots declined during the season, whereas those of Ca, Mg, B, and Mn rose. Element concentrations in the tissues indicated that mobilization of elements into new shoots from old leaf and woody stem tissues occurred. In an average crop (17 Mg/ha), 8.5 kg N/ha and 14.7 kg K/ha were removed from the cranberry bog. Vegetative growth (dry weight, upright length) was positively correlated with N-P-K supply, but the highest yields were associated with 335 kg N-P-K/ha. Upright density, percent of uprights flowering, and fruit set were the important determinants of yield. These variables were proposed as standards for data collection. Growing degree day (GDD) accumulations were recorded during this study using a base temperature of 6.5C (lower than previously recommended). Based on GDD accumulations at the canopy level, the correct base temperature for cranberries is most likely 4.5C or lower. However, for a single location over several years, day number was superior to GDD as a predictor of developmental and nutritional status. A period of stable element concentration in new shoot tissue (10 August to 15 September) was identified and recommended as the time to collect cranberry tissue samples for analysis. Mixed vegetative and flowering new upright tips were recommended as the tissue to sample, and standards for 'Early Black' were proposed. Element concentrations in 'Howes', 'Stevens', 'Pilgrim', 'Bergman', and 'Franklin' were determined and compared to the 'Early Black' standard values.

Propagation and Scattering of Waves by Terrain Features

Davis, Bradley A. 07 July 2000 (has links)
The intent of this dissertation is to obtain estimates of the effects of natural terrain features on the propagation and scattering of waves. It begins with the rough knife obstruction case, moves into rough surfaces and finally concludes with several approaches to a foliage covered rough surface. Each of these problems is encountered in radar, remote sensing and communication systems. The first topic in this dissertation is the study of the effect of random edge roughness on the diffraction of a wave. This has been accomplished by approximating the field beyond the diffracting half-plane through the use of spectral techniques and the Kirchhoff approximation. The relationships developed for the mean or average diffracted field and the incoherent diffracted power are studied for a range of electrophysical parameters that are representative of the situation encountered in a point-to-point communications link with blockage by a rough edged half plane. The interpretation of the results is facilitated by the observation that the total diffracted field is a superposition of the incident field and the edge-diffracted field. When the roughness on the edge increases, the edge diffracted-field becomes more incoherent and the phase interference consequently diminishes, leading to an attenuation of the oscillations in the coherent or mean total field. The model also addresses the effects of the knife edge in directions off the line-of-sight path as well as its effects on pulse propagation. Next, rough surface scattering effects are addressed. Extending the idea of the knife edge diffraction, this dissertation builds on the topic of a wedge on a plane by adapting the Method of Multiple Ordered Interactions (MOMI) to the dielectric surface. In this development, the coupled integral equations governing the scattering by a dielectric surface are combined into a single equation wherein the lossy dielectric enters the solution as a perturbation of the result for a perfectly conducting surface. Hence, the solution is not only exact, but as the loss increases, the convergence is rapid. Next, the Kirchhoff approximation is expanded to a two-frequency form for use with the later chapters which deal with pulse scattering by rough surfaces. Example waveform calculations are given. Propagation and scattering by a volume of scatterers over a surface is then examined. Starting from the radiative transfer equations, a model is developed herein for scattering from vegetated rough terrain. It assumes completely incoherent scattering and includes contributions from both the vegetation and the surface scattering along with a relatively simple accounting for their interaction. The model is developed into a form that easily separates the three primary components of the scattering problem - the radar system, the geometry, and the environment, and then recombines them through a multiple convolution. Extending the basic model to volumes for which multiple scattering is important is accomplished through the use of effective parameters. These effective parameters are obtained by comparing the model with pulsed radar data at normal incidence, i.e., looking directly down through the foliage and onto the ground. Hence, our overall model is a hybrid approach wherein the basic physics are retained in the simple solution. It is then extended to a more complicated environment through the use of these effective parameters. Example waveform calculations are given. The simple model assumes that multiple interactions are insignificant and that only narrow-band signals and narrow-beamwidth antenna patterns are used. Consequently, a more general radiative transfer approach is applied to the propagation of a beam through the random medium. This effort is a test of the narrow beamwidth and forward-backward scattering approximations implicit in the convolutional model. Next, the same convolutional model is developed using wave theory in order to clarify the assumptions and lend some physical meaning to the free parameters of the convolutional model. First the single scatter theory, with strictly forward and backward scattering is shown to be equivalent to the convolutional approach derived with radiative transfer theory. Next, multiple scattering in a discrete random medium is investigated in the "extended" Twersky approximation [Tsolakis, 1985]. This development leads to the mean Green's function for the medium, a form of the Distorted Wave Born Approximation and to a two-frequency radiative transfer equation. This transfer equation is then shown to simplify under the forward-backward assumption, eventually leading to a form which is compatible with the convolutional result. Finally, the effects of multiple scattering between the volume and its boundary, the rough surface, have been investigated. Using a numerical implementation (MOMI) of a scatterer over a rough surface, the orders of significant multiple interactions between the rough surface and the volume scattering components have been simulated. It is demonstrated that foliage components well above the rough surface may be treated as non-interacting; this includes components other than the trunks, which were not simulated. However, it is evident that multiple scattering effects may be significant for large objects near the rough surface. This work has been supported by grants from the Bradley Department of Electrical and Computer Engineering, National Science Foundation, and the Virginia Space Grant Consortium. Additional support has been provided by the U.S. Air Force at Hansom Airforce Base under grant F19628-96-C-0071, and U.S. Army Research Office under grant DAAG55-97-1-0164. / Ph. D.

A study of laminar flame propagation and quenching distances

Friedman, Raymond, January 1948 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1948. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Air as a rooting medium : an experimental air-mist chamber system for rooting cuttings using Forsythia x intermedia

Dodd, Melvin Ennis January 2011 (has links)
Digitized by Kansas Correctional Industries

A statistical study of the effects of the number of pecans per pot on the uniformity of the seedlings in size

Messina, William S. (William Samuel) January 1973 (has links)
No description available.

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