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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.
171

Live crown ratio model and lumber recovery for intensively managed loblolly pine

Parajuli, Kamana 09 January 2025 (has links)
Loblolly pine is a commonly planted pine species in the Southern US which is intensively managed as well as a major contributor to the timber industry. Various silvicultural treatments are commonly applied to pine plantations including thinning and sometimes pruning. Tree crowns contain the active photosynthesis region and play a vital role in tree growth. Among various tree crown measurements, live crown ratio (LCR) is derived from height to live crown base (HLCB) and total tree height. Accurate measurement of HLCB is basis for live crown ratio prediction. Due to numerous definitions and practical considerations, HLCB and crown structure are difficult and slow to measure accurately. Despite this, LCR is a useful predictor in various growth and yield models. Due to the challenges in measuring tree crowns, accurate live crown ratio prediction models are useful. The LCR model of (Dyer and Burkhart, 1987) was refit with intensively managed plantation (IMP) data. The parameters were significant, and the residual plots showed no concerning patterns but the prediction of height to live crown base for pruned trees was not logical as it sometimes predicted HLCB lower than pruning height. To address this, the base model was modified to accommodate the pruning effect and provide logical predictions. LCR is in range of 0 - 1 and HLCB is greater or equal to pruning height. If trees are not pruned, it reverts to the original model. The models were validated with a dataset of IMP measurements not used in fitting. Validation statistics suggest the model performs nearly as well as the original, unconstrained base model. It is expected that the new model will be useful for forest managers to predict LCR of both pruned and unpruned trees. The second part of the study is to understand the importance of common tree variables in predicting the lumber recovery in planted loblolly pine. A random forest model was used to determine the variable importance of DBH, total tree height and live crown ratio for total board ft., high-grade, and high-grade lumber proportion compared to total board ft. DBH ranked at the first position followed by total tree height and live crown ratio similarly ranked for volume and high-grade lumber volume. For proportions of high-grade lumber, tree height was at top rank followed by LCR, and DBH. However, the effect of these variables for lumber recovery was not explored. It is suggested that future work can explore parametric model forms for accurately predicting lumber recovery using simple, easy to measure tree variables. / Master of Science / Loblolly pine plantations are found in large areas of southern United States. Significant investments are made for maximizing wood production and economic benefits. The growth of trees is largely governed by its crown which is the green foliage found in upper parts of tree. Planted trees are often thinned to provide crown sufficient light for improved growth. Tree crowns are sometimes pruned to reduce knot size and improve lumber quality. If we can understand how these activities affected the crown length of trees, we can manage our plantation accordingly. With this motivation, the live crown ratio which is the ratio of length of live crown and total tree height was modeled. An existing live crown ratio model for planted loblolly pine trees was modified to provide logical predictions for pruned trees and was updated with newer data. Simple tree measurements like tree diameter, height and age were used in the model. Common tree variables were used because LCR is derived from height to live crown base which is difficult to measure in field. The new model will be useful to forest managers for predicting the growth of loblolly pine plantations subjected to pruning. Similarly, an attempt is made to explore the various standing tree characteristics affecting the amount of lumber that can be obtained. This will assist in understanding the lumber grade by using common tree measurements and value of a stand from lumber production side can be known.
172

Establishment of blackberries and detection and management of raspberry crown borer

Heard, Edward, January 2006 (has links)
Thesis (M.S.)--Mississippi State University. Department of Plant and Soil Sciences. / Title from title screen. Includes bibliographical references.
173

Root morphology and sexual dimorphism : size standards for crown and root dimenstions in adolescents

Couch, William Max , Jr., January 2007 (has links) (PDF)
Thesis (M.S. )--University of Tennessee Health Science Center, 2007 / Title from title page screen (viewed on June 10, 2008). Research advisor: Edward F. Harris, PhD Document formatted into pages (xii,163 p. : ill.). Vita. Abstract. Includes bibliographical references (p. 109-125).
174

Pseudorotaxanes and Supramolecular Polypseudorotaxanes Based on the Dibenzo-24-Crown-8/Paraquat Recognition Motif

Huang, Feihe 06 November 2003 (has links)
The research presented in this thesis focused on pseudorotaxanes and supramolecular polymers based on a new recognition motif, the dibenzo-24-crown-8/paraquat recognition motif. Main kinds of pseudorotaxanes and rotaxanes and various protocols used for the study of them were discussed first. By preparation and characterization of a series of pesudorotaxanes based on DB24C8 and paraquat derivatives, it was found that these complexes were stabilized by N+...O interactions, C-H...O hydrogen bonding, and face-to-face p-stacking interactions. Because methyl protons of paraquat are involved in hydrogen bonding to the host, the substitution of any methyl hydrogen on paraquat causes apparent association constant of the pseudorotaxane to decrease. The concentration dependence of apparent association constants, Ka,exp, of fast exchange host-guest systems was studied for the first time by using complexes based on viologens and crown ethers as examples. While the bis(hexafluorophosphate) salts of paraquat derivatives are predominantly ion paired in acetone (and other low dielectric constant solvents presumably) the complex based on dibenzo-24-crown-8 and paraquat is not ion paired in solution, resulting in concentration dependence of Ka,exp. However, four complexes of two different bis(m-phenylene)-32-crown-10 (BMP32C10) derivatives and bis(p-phenylene)-34-crown-10 (BPP3C10) with viologens are ion paired in solution, as shown by the fact that Ka,exp is not concentration dependent for these systems involving hosts with freer access to bound guests. X-ray crystal structures support these soluton-based assessments in that there is clearly ion pairing of the cationic guest and its PF6- counterions in the solid states of the latter four examples, but not in the former. The complexes based on the new dibenzo-24-crown-8/paraquat recognition motif are thus different from the complexes based on two old recognition motifs: the BPP34C10/BMP32C10-paraquat and DB24C8-ammonium motives. In order to compare these recognition motives further, the selectivity between two hosts, DB24C8 and BPP34C10, and two guests, dimethyl paraquat and dibenzyl ammnonium salt, was discussed. By individual and competitive complexation studies, it was demonstrated that DB24C8 is a better host than BPP34C10 for paraquat, and that paraquat is a better guest than dibenzyl ammonium salt for DB24C8. Finally the DB24C8-paraquat recognition motif was successfully applied in the preparation the first star-shaped supramolecular polymer based on a tetraparaquat guest and a DB24C8 functionalized polystyrene oligomer. A model system based on this guest and DB24C8 was also studied for comparison. It was found that the complexation in these two systems is cooperative, as are most biological complexations of multitopic species. Due to the ready availability of DB24C8 and paraquat derivatives, the new recognition motif should prove to be very valuable for self-assembly of other more sophisticated supramolecular systems. / Master of Science
175

Análise da distribuição das tensões nas estruturas de suporte de overdentures, rebordo residual e implantes, com sistema de conexão de coroas cônicas (Syncone-Dentsply). / Analysis of the tensions distribution in the structures of overdentures support, residual alveolar ridge and implants, with connection of conical crowns system (Syncone-Dentsply)

Guariglia, Ana Cristina Aurora Rosa Perasso 22 March 2007 (has links)
O sistema de osseointegração desenvolvido por Branemark revolucionou o campo das reabilitações protéticas, incentivando os profissionais a indicar e realizar próteses do tipo overdentures. Estes dispositivos representam uma ótima alternativa para solucionar os problemas dos pacientes desdentados, insatisfeitos por diversos fatores. Várias são as associações entre os implantes e os sistemas de conexões empregados em overdentures. A literatura e a prática clínica fazem observar que na dependência do sistema de conexão empregado, há uma diferença no comportamento biomecânico, realizado por este conjunto: prótese/implante/conexão. Desta forma, é importante analisar como as tensões se distribuem sobre as estruturas que suportam estas cargas, uma vez que não existe o ligamento periodontal ao redor dos implantes que promove o mecanismo fisiológico, natural nos dentes. Assim, o objetivo desta investigação foi de avaliar, com o auxílio do método fotoelástico, o comportamento da distribuição das tensões em sobredentaduras (overdentures), suportadas por quatro implantes Ankylos®/ Dentsply®, utilizando-se o sistema protético de conexão de coroas cônicas Syncone®/ Dentsply®, onde se comparou duas formas de distribuição dos implantes, na primeira (CPM1) os implantes foram posicionados nas regiões de incisivos centrais e pré-molares e o segundo (CPM2) os implantes estavam posicionados nas regiões de caninos e pré-molares. Os modelos receberam cargas de forma crescente de 0,0 a 9,0 kg e, as tensões resultantes nas estruturas de suporte, foram analisadas fotoelasticamente. De acordo com a metodologia empregada nesta pesquisa, somos levados a concluir que: 1) Quando se associa o sistema Syncone® com overdenture ou sobredentadura, apoiada e retida sobre quatro implantes, sendo 2 localizados na região de incisivos centrais e 2 situados, diametralmente opostos, na região de segundos pré-molares na mandíbula - CPM1 - o rebordo residual é quem recebe a maior quantidade de tensões em relação aos implantes; 2) Quando se associa o sistema Syncone® com overdenture ou sobredentadura, apoiada e retida sobre 4 implantes, dispostos 2 a 2, bilateralmente e diametralmente opostos, nas regiões de caninos e pré-molares, na mandíbula (CPM2), as maiores tensões são transmitidas ao rebordo residual, sendo que os implantes suportes resultam mais preservados; 3) Comparativamente, o CPM2, aparenta ter transmitido menores tensões aos implantes que o CPM1; 4) Os implantes são preservados quanto à ocorrência de uma sobrecarga, durante a máxima intercuspidação dos arcos dentários, quando se emprega o sistema Syncone® associado à overdenture ou sobredentadura. / The osseo-integrated system develop by Branemark has revolutionized the prosthetic rehabilitation field, encourage the professionals to indicate and perform prostheses like overdentures. These devices represent an optimal alternative to solve the full dentures patient?s problems, dissatisfied for diverse factors. There are several associations between implants and prosthetic connectors employees for overdentures. The literature and the clinic practice may observe that according of the connection system employed, there is a difference into the biomechanical behavior, realized for this set: prostheses/implant/connection. From this forms, it is important to analyze how the tensions are distributing on the structures subject that support these loads, since it doesn\'t exist the periodontal ligament around the implants, what promotes the physiological mechanism of the natural teeth. Such, the purpose from this investigation was appraising, with the aid of the photoelastic method, the distribution way from the tensions at the overdentures, supported by four implants Ankylos®/ Dentsply, by using the prosthetic system of connection of conic crowns ? Syncone®/ Dentsply, were applied loads from 0,0 to 9,0kg, in crescent forms and, the tensions resulting on the support structures, have been analyzed by the photoelasthic method. Where two forms of distribution of the implantations were compared, first (CPM1) the implants were located at the regions of the central incisors and pre-molar, and as (CPM2) the implants were located at the regions of canines and pre-molar. The models had received loads of increasing form, from 0,0 to 9,0 kg and, the resultant tensions in the support structures, had been analyzed by the photoelastic method. In agreement with the methodology used in this research, we are led to conclude that: 1) When the overdenture is associated with Syncone® system, supported and retained by 4 implants, being 2 located in the region of central incisors and 2, diametrical opposing ones, in the region of the second pre-molar (CPM1) the residual alveolar ridge is who receives the biggest amount of tensions in relation to the implants; 2) When the overdenture is associated with Syncone® system, supported and retained by 4 implants, bilaterally and diametrical opposing ones, in the regions of canine and pre molar (CPM2), the biggest tensions were transmitted to the residual alveolar ridge, being the implants supports resulted more preserved; 3) Comparatively, the CPM2, seems to have transmitted less tensions to the implants than the CPM1; 4) The implants were preserved as the occurrence of an overload, during the maximum intercuspidação of the dental arcs, when the overdenture associated with Syncone® system has been used.
176

The Honour of the Crown: Making Sense of Crown Liability Doctrine in Crown/Aboriginal Law in Canada

2014 January 1900 (has links)
Simply put, Crown liability doctrine in Crown/Aboriginal Law in Canada is a mess. Demonstrably, there are fiduciary-based duties, fiduciary-based principles, an over-arching honour of the Crown principle, Crown honour-based duties, and a constitutional Crown/Aboriginal “reconciliation” imperative. How the various pieces are meant to fit together is atypically unclear. In this project, Ronald Dworkin’s rights thesis is invoked as a conceptual tool in an attempt to help bring some order to the disarray. It is argued that the Supreme Court of Canada made a fundamental (Dworkinian) mistake in the manner in which they adopted fiduciary concepts into the core of Crown/Aboriginal Law; that this mistake has led to a dysfunctional doctrine; and that the Supreme Court has implicitly acknowledged their error and are now in the process of incrementally mending their materially flawed doctrine. Crown liability doctrine in Crown/Aboriginal Law in Canada is now centrally organized around the principle that the honour of the Crown must always be upheld in applicable government dealings with Aboriginal peoples. Enforceable Crown honour-based “off-shoot” duties operate to regulate the mischief of Crown dishonour in constitutional contexts. The Supreme Court has now stated that a (non-conventional and fundamentally unresolved) Crown/Aboriginal fiduciary obligation is one such “off-shoot” duty. This emergent “essential legal framework” is meant to protect and facilitate the over-arching project of reconciling the pre-existence of Aboriginal societies with the de facto sovereignty of the Crown, which reconciliation project, it is argued here, is to be fundamentally undertaken by the executive and legislative branches of government working collaboratively with Aboriginal peoples. The judicial branch of government is then largely limited to the more modest task of regulating the mischief of constitutional Crown dishonour. This project ultimately purports to theorize this relatively new Crown honour-based framework, and to conceptualize what residual role there is for fiduciary accountability to play in applicable Crown/Aboriginal contexts moving forward. It is concluded there is likely only a narrow jurisdiction remaining for fiduciary accountability in Crown/Aboriginal contexts, which jurisdiction appears destined to take the form of conventional fiduciary doctrine which, as will be demonstrated, has itself been fundamentally reconfigured in recent years.
177

Análise da distribuição das tensões nas estruturas de suporte de overdentures, rebordo residual e implantes, com sistema de conexão de coroas cônicas (Syncone-Dentsply). / Analysis of the tensions distribution in the structures of overdentures support, residual alveolar ridge and implants, with connection of conical crowns system (Syncone-Dentsply)

Ana Cristina Aurora Rosa Perasso Guariglia 22 March 2007 (has links)
O sistema de osseointegração desenvolvido por Branemark revolucionou o campo das reabilitações protéticas, incentivando os profissionais a indicar e realizar próteses do tipo overdentures. Estes dispositivos representam uma ótima alternativa para solucionar os problemas dos pacientes desdentados, insatisfeitos por diversos fatores. Várias são as associações entre os implantes e os sistemas de conexões empregados em overdentures. A literatura e a prática clínica fazem observar que na dependência do sistema de conexão empregado, há uma diferença no comportamento biomecânico, realizado por este conjunto: prótese/implante/conexão. Desta forma, é importante analisar como as tensões se distribuem sobre as estruturas que suportam estas cargas, uma vez que não existe o ligamento periodontal ao redor dos implantes que promove o mecanismo fisiológico, natural nos dentes. Assim, o objetivo desta investigação foi de avaliar, com o auxílio do método fotoelástico, o comportamento da distribuição das tensões em sobredentaduras (overdentures), suportadas por quatro implantes Ankylos®/ Dentsply®, utilizando-se o sistema protético de conexão de coroas cônicas Syncone®/ Dentsply®, onde se comparou duas formas de distribuição dos implantes, na primeira (CPM1) os implantes foram posicionados nas regiões de incisivos centrais e pré-molares e o segundo (CPM2) os implantes estavam posicionados nas regiões de caninos e pré-molares. Os modelos receberam cargas de forma crescente de 0,0 a 9,0 kg e, as tensões resultantes nas estruturas de suporte, foram analisadas fotoelasticamente. De acordo com a metodologia empregada nesta pesquisa, somos levados a concluir que: 1) Quando se associa o sistema Syncone® com overdenture ou sobredentadura, apoiada e retida sobre quatro implantes, sendo 2 localizados na região de incisivos centrais e 2 situados, diametralmente opostos, na região de segundos pré-molares na mandíbula - CPM1 - o rebordo residual é quem recebe a maior quantidade de tensões em relação aos implantes; 2) Quando se associa o sistema Syncone® com overdenture ou sobredentadura, apoiada e retida sobre 4 implantes, dispostos 2 a 2, bilateralmente e diametralmente opostos, nas regiões de caninos e pré-molares, na mandíbula (CPM2), as maiores tensões são transmitidas ao rebordo residual, sendo que os implantes suportes resultam mais preservados; 3) Comparativamente, o CPM2, aparenta ter transmitido menores tensões aos implantes que o CPM1; 4) Os implantes são preservados quanto à ocorrência de uma sobrecarga, durante a máxima intercuspidação dos arcos dentários, quando se emprega o sistema Syncone® associado à overdenture ou sobredentadura. / The osseo-integrated system develop by Branemark has revolutionized the prosthetic rehabilitation field, encourage the professionals to indicate and perform prostheses like overdentures. These devices represent an optimal alternative to solve the full dentures patient?s problems, dissatisfied for diverse factors. There are several associations between implants and prosthetic connectors employees for overdentures. The literature and the clinic practice may observe that according of the connection system employed, there is a difference into the biomechanical behavior, realized for this set: prostheses/implant/connection. From this forms, it is important to analyze how the tensions are distributing on the structures subject that support these loads, since it doesn\'t exist the periodontal ligament around the implants, what promotes the physiological mechanism of the natural teeth. Such, the purpose from this investigation was appraising, with the aid of the photoelastic method, the distribution way from the tensions at the overdentures, supported by four implants Ankylos®/ Dentsply, by using the prosthetic system of connection of conic crowns ? Syncone®/ Dentsply, were applied loads from 0,0 to 9,0kg, in crescent forms and, the tensions resulting on the support structures, have been analyzed by the photoelasthic method. Where two forms of distribution of the implantations were compared, first (CPM1) the implants were located at the regions of the central incisors and pre-molar, and as (CPM2) the implants were located at the regions of canines and pre-molar. The models had received loads of increasing form, from 0,0 to 9,0 kg and, the resultant tensions in the support structures, had been analyzed by the photoelastic method. In agreement with the methodology used in this research, we are led to conclude that: 1) When the overdenture is associated with Syncone® system, supported and retained by 4 implants, being 2 located in the region of central incisors and 2, diametrical opposing ones, in the region of the second pre-molar (CPM1) the residual alveolar ridge is who receives the biggest amount of tensions in relation to the implants; 2) When the overdenture is associated with Syncone® system, supported and retained by 4 implants, bilaterally and diametrical opposing ones, in the regions of canine and pre molar (CPM2), the biggest tensions were transmitted to the residual alveolar ridge, being the implants supports resulted more preserved; 3) Comparatively, the CPM2, seems to have transmitted less tensions to the implants than the CPM1; 4) The implants were preserved as the occurrence of an overload, during the maximum intercuspidação of the dental arcs, when the overdenture associated with Syncone® system has been used.
178

A post construction evaluation of an interior landscape and related spaces

Warren, Gregory Alan. January 1979 (has links)
Call number: LD2668 .T4 1979 W37 / Master of Landscape Architecture
179

POLYMORPHISM OF FOUR ENANTIOTROPIC CRYSTALLINE SYSTEMS CONTAINING Ni(II), H<sub>2</sub>O, 15-Crown-5 AND NO<sub>3</sub><sup>-</sup>

Siegler, Maxime Andre 01 January 2007 (has links)
The series of compounds [M(H2O)2(15-crown-5)](NO3)2, M = Mg, Mn, Co, Cu and Zn, has been extended to include two new phases for M = Fe and two new phases for M = Ni. The system [M(H2O)2(15-crown-5)](NO3)2 is remarkable for having many high-Z’ phases (Z’ > 1) with similar packing and for having solid-solid phase transitions through which there is no significant loss of crystallinity. The synthesis of the analogous Ni complex was carried out. Single-crystal X-ray diffraction showed that the coordination of the Ni2+ ion is different from that of the other six M2+ ions in the system [M(H2O)2(15-crown- 5)](NO3)2. High temperature phases with high Z’ (8) were isolated for M = Mg, Fe and Zn. The refinements of such phases are challenging because of the lack of information in the diffraction patterns. Full details of the refinements for these three phases are discussed. Six other Ni(II) complexes consisting of Ni2+, NO3-, 15-crown-5 and different solvents were found when efforts were made to synthesize the compound [Ni(H2O)2(15-crown- 5)](NO3)2. In these chemically different environments, the Ni2+ ions are not coordinated by the 15-crown-5 molecules; rather, one-dimensional H-bonded chains are formed from uncomplexed 15-crown-5 molecules and the Ni(II) complexes. Among these six Ni(II) complexes, the compounds [Ni(H2O)6](NO3)2·(15-crown-5)·H2O, [Ni(H2O)6](NO3)2·(15-crown-5)·2H2O and [Ni(H2O)2(MeCN)(NO3)2]·(15-crown- 5)·MeCN were found to have reversible solid-solid phase transitions between structurally related phases. In all of these transitions, no significant crystal damage was detectable. The two latter systems are unusual because their phase sequences include three transitions and four phases between 90 and 295 K and because of the existence of high-Z’ phases. These high-Z’ phases are best depicted as being intermediate to low- and hightemperature phases. A method based on thermal analyses and X-ray diffraction has been developed for studying such sets of phase transitions.
180

Prosecutor Selected Youth Diversion: Identifying the Circumstances and Conceptualizing the Cases

Coady, Kyle N. P. 29 August 2012 (has links)
Crown selected youth diversion has received little academic attention in Canada. As a process that channels offenders out of the formal legal system, diversion purports to achieve contradictory self-serving system and offender-based goals. Using 50 randomly selected prosecution files – half of which the Crown diverted and half of which the Crown prosecuted – a mixed method investigation of diversion assesses cases through quantitative content analysis and grounded theory method. Based on the quantitative analysis, it is argued that there is an emerging patterned nature of Crown selected diversion that is not completely benign. This patterned nature of diversion unearths a distinctive discourse of diversion/non-diversion. Qualitatively, it is argued that the cases are organized around three temporal moments that create an area for distinctions to be made in terms of threat, responsibility, (in)tolerableness and recourse. Seemingly, there is a persistent paradoxical existence of the diversion process that emerges from the case files.

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