To see the other types of publications on this topic, follow the link: PIAE.
Dissertations / Theses on the topic 'PIAE'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 dissertations / theses for your research on the topic 'PIAE.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
1
Eastman, Ryan S. "Experimental Investigation of Steel Pipe Pile to Concrete Cap Connections." BYU ScholarsArchive, 2011. https://scholarsarchive.byu.edu/etd/2628.
Full textAbstract:
Piles are often used to resist vertical and lateral loads when shallow foundations are inadequate or uneconomical. A critical part in designing pile foundations is the pile-to-cap connection. When a moment resisting connection is desired, reinforcement is typically used between the pile and the cap. A pile-to-cap connection with sufficient pile embedment depth, however, may provide similar results. One model that is currently used to determine the capacity of a pile-to-cap connection was developed by Marcakis and Mitchell for steel members embedded in concrete. This model considers an embedment mechanism that resists rotation at the connection. Recent testing has shown, however, that this model is conservative and that additional mechanisms contribute to the strength of the connection. An experimental study was conducted to investigate pile-to-cap connections for pipe piles without reinforcement. Three pile-to-cap specimens with varying pile embedment depth were loaded laterally to failure. The results from the testing confirm that pile-to-cap connections with shallow pile embedment depth have significant stiffness. An improved model was developed to estimate elastic and ultimate capacities of embedded connections. In addition to the embedment mechanism used by Marcakis and Mitchell, this model includes a bearing mechanism at the end of the pile. For pile-to-cap connections with a large pile bearing area to pile embedment depth ratio, this bearing mechanism provides more strength than the embedment mechanism. For pile-to-cap connections with a small pile bearing area to pile embedment depth ratio, this bearing mechanism has little contribution to the strength of the connection.
2
Cuthbertson-Black, Robert. "The interaction between a flighted steel pipe pile and frozen sand." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ57528.pdf.
Full text
3
Meyer, Natalie Jo. "Soil and plant response to slash pile burning in a ponderosa pine forest." Thesis, Montana State University, 2009. http://etd.lib.montana.edu/etd/2008/meyer/MeyerN1208.pdf.
Full textAbstract:
Slash pile burning is the most common method of forest residue disposal following ponderosa pine restoration harvests, which are intended to reduce the risk of catastrophic fire and restore the historical structure and function of forests in western Montana. The impact of high-intensity, long-duration fire (pile burning) on soil processes and plant community dynamics is not well understood. The objectives of this study were: (1) to characterize the influence of slash pile burning on soil nutrient availability, soil microbial activity, and arbuscular mycorrhizal (AM) infection; (2) to compare seeding and soil amendment effects on burn scars. In May 2006, slash piles were burned in a ponderosa pine stand near Florence, Montana and 45 scars were sampled. Soil samples were collected from three locations in each slash pile to a depth of 10 cm and characterized for available soil NH4 +-N, NO3 - -N, potentially mineralizable nitrogen (PMN), and total C and N, water-soluble PO4 3- -P, microbial biomass, and mycorrhizal inoculum potential (MIP). In the burned center, soil NH4 +-N was greatest one month post-burn and remained elevated one year later. There was no observable increase in NO3 - -N until one year post-burn. Soluble PO4 3- -P was not impacted by burning. Microbial biomass was reduced by burning and did not recover one year later. Pile burning greatly reduced MIP. In October 2006, fire scars were either seeded with native graminoids or left non-seeded, divided into subplots, and assigned to one of five treatments: control, addition of local organic matter, scarification, scarification and organic matter addition, or scarification and commercial compost addition. Soils were monitored for the previously measured soil parameters and resin-sorbed inorganic N. Scarification with organic matter amendment and scarification with compost amendment both ameliorated soil properties. Seeding most effectively increased plant cover and suppressed non-native invasive species, while scarification or scarification with organic matter amendment further improved early plant establishment. Collectively, these data help characterize the impacts of slash pile burning as a management technique in ponderosa pine forests and illustrate potential treatments for restoring burn pile scars.
4
Seymour, Geoff, and Aregai Tecle. "Impact of Slash Pile Size and Burning on Ponderosa Pine Forest Soil Physical Characteristics." Arizona-Nevada Academy of Science, 2003. http://hdl.handle.net/10150/296601.
Full text
5
Rodrigues, Paula Alexandra Pinto. "Archaeological roman glasses: comparative characterisation by non-destructive analytical techniques." Master's thesis, Faculdade de Ciências e Tecnologia, 2011. http://hdl.handle.net/10362/6145.
Full text
6
Bejjani-Ghauch, Alice. "Apport de l’analyse élémentaire (IBA) et moléculaire (ToF-SIMS) par faisceaux d’ions à l’étude de matériaux d’intérêt environnemental et pharmaceutique." Thesis, Lyon 1, 2009. http://www.theses.fr/2009LYO10302.
Full textAbstract:
Les faisceaux d’ions de l’ordre du MeV permettent la mise en œuvre de techniques d’analyse tant élémentaire (Ion Beam Analysis-IBA) que moléculaire (Time of Flight Secondary Ion Mass Spectrometry) pour des matériaux solides peu étudiés en raison de leur hétérogénéité: les mélanges de poudres. La première partie de notre travail est à placer dans le contexte de l’étude de la photodégradation des pesticides dans l’environnement à travers l’analyse ToF-SIMS de pesticides imprégnés dans des sols naturels. A partir d’une étude comparative du phénomène induit sur des dépôts sur des substrats homogènes nous présentons les résultats de la cinétique de dégradation pour plusieurs pesticides avec en particulier des valeurs de demi-vies. La seconde partie s’inscrit dans le processus de contrôle de produits pharmaceutiques commerciaux à analyser en l’état. Nous montrons que la quantification du principe actif (p.a.) en présence d’excipients est possible: -par les techniques IBA quand le p.a. contient des hétéroatomes non présents dans les excipients. La précision (<7%) est alors la plupart du temps bien meilleure que les exigences du contrôle industriel. -par la technique ToF-SIMS dans tous les cas mais dans des domaines définis par les courbes d’étalonnage pour avoir les meilleures sensibilités. Ces restrictions dépendent de la nature des partenaires (p.a. et excipients) et mettent en évidence des effets de matrice dont l’étude doit permettre l’amélioration de la préparation de tels échantillons en vue d’analyses plus performantes. Ces techniques dont les avantages et les limitations sont discutés, sont à notre connaissance utilisées pour la première fois sur de tels matériaux « réels »The aim of this study is to analyze heterogeneous organic matter by exhibiting analytical difficulties by classical techniques under solid state. The first part of this work is dedicated to the study of pesticides photodegradation impregnated in soils by ToF-SIMS technique. A comparative investigation of the induced phenomenon obtained with the same pesticides deposited as thin layer on a neutral support helped in studying the degradation kinetics of those pesticides especially their half-lives. The second part is dedicated to the development of new analytical method for the analysis of commercialized pharmaceutical compounds without prior sample preparation. We have demonstrated the possibility of active ingredient (A.I.) quantification in the presence of the excipients by the following analytical techniques: IBA techniques if the A.I. contains an heteroatom, however, absent in the excipients. The precision (< 7%) is found to be in the majority of the studied cases within the analytical standards of the quality control processes. ToF-SIMS technique for all drugs however within a specific range of concentration defined by the calibration curves for improved sensitivities. These restrictions in the dynamic concentration range depend on the nature of the mixtures A.I. / Excipients on hand and show evidence of the matrix effect on the other hand. A deep investigation on the matrix nature should improve the sample preparation method for more performance analysis. To our knowledge, it is the first time that the above mentioned techniques whose analytical advantages and limitations have been discussed were applied to such solid matrix samples
7
Seymour, Geoff, and Aregai Tecle. "Impact of Slash Pile Burning on Physical and Chemical Characteristics of Soil in a Ponderosa Pine Forest." Arizona-Nevada Academy of Science, 2002. http://hdl.handle.net/10150/296577.
Full text
8
Itoh, Yoshito, Yasuo Kitane, and Xiao Chen. "Evaluation of repair design on corrosion-damaged steel pipe piles using welded patch plates under compression." 土木学会, 2011. http://hdl.handle.net/2237/18848.
Full text
9
ITOH, Y., Y. KITANE, and X. CHEN. "Compression Behaviors of Thickness-Reduced Steel Pipes Repaired with Underwater Welds." Elsevier, 2011. http://hdl.handle.net/2237/18823.
Full text
10
Chaudhry, Anjum Rashid. "Static pile-soil-pile interaction in offshore pile groups." Thesis, University of Oxford, 1994. http://ora.ox.ac.uk/objects/uuid:7b4c8d56-184f-4c8d-98c9-2d9c69a1ef55.
Full textAbstract:
This thesis is a theoretical study, using both finite element and boundary element methods, of the behaviour of single-piles and pile groups under vertical and lateral loading. It offers an improved understanding of the soil-structure interaction that occurs in pile groups, particularly closely spaced piles subjected to lateral loads. The potential of a two- dimensional idealisation of what is a three-dimensional problem is demonstrated by achieving real insight into the complex nature of pile-soil and pile-soil-pile interaction in pile groups. A new load transfer mechanism is presented for a rigid, axially loaded vertical pile. From this an improvement is then derived to the analytical solution for pile head settlement given by Randolph and Wroth (1978). The improved mechanism has the further merit that it can be applied also to solutions for flexible piles and pile groups. The improved analytical solution is further adapted in the development of two correcting layers specifically for vertically loaded piles to model infinite boundaries in the finite element model. The correcting layers help in establishing superiority of the finite element method over the boundary element method. To model pile-soil interaction, a purely cohesive interface element is developed and then validated by performing various two-dimensional test problems, including stability analysis of flat surface footings. Footing-soil interface tension is successfully modelled in this way - an outcome that entails a significant modification to the Hansen (1970) bearing capacity solution. Stability analysis is also carried out of conical footings using a three-dimensional finite element model: the results help to explain the applicability of the existing bearing capacity theories to conical footings. The ultimate lateral soil reaction is determined and various pile loading stages are investigated through parametric studies. Study of the stage immediately following pile installation (i.e. the consolidation stage) highlights the need to develop an effective stress analysis for laterally loaded piles. Pile-soil interaction is studied using the cohesive interface element presented earlier, which proves to be quite successful in smoothing out the stress discontinuities around the pile. A new material model for frictional soils is presented, and validated by using it to model an extension test: it captures well post-peak behaviour and takes care of the effects of dilation on the response of laterally loaded piles. Finally, mechanisms of interaction in closely spaced pile groups are studied. Simple analytical expressions are derived which quantify the effects of interaction. A new method of analysis is presented for single-piles and pile groups which offers a considerable degree of reliability without having to do either impossibly expensive full scale field tests or prohibitively expensive full three-dimensional analysis using the currently available computers.
11
Höglund, Madicken, and Marcus Larsson. "Grundförstärkning med pålar i berg : I befintlig konstruktion med begränsat utrymme." Thesis, KTH, Byggteknik och design, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-287735.
Full textAbstract:
This study has been done in order to examine which type of pile, pile driving- and waterproofing methodsare most suited for an existing building. A building that will undergo an extensive reinforcement of itsfoundation.The study has been made in regard to the following conditions:● Different types of clay soil (Cohesion soil)● Underlying rock structure with heavy incline (8° slope)● Sensitive environment for vibrations and ground displacements● Limited accessibility (Room and maximum weight)● Compressive and tensile forces● Pool (Water environment)To answer the questions of statement a scientific literature study, interview with a foundation expert,calculations in sizing, but also time and cost analysis has been conducted. A site visit to an object ofreference, Nya Krav Himmerfjärdsverket, occurred where a reconstruction of an existing building withextensive work of reinforcement to its’ foundation was in progress.The steel pipe pile with anchor and steel core pile are the best pile types in such conditions as compressiveand tensile forces, clay soil with underlying inclined rock bed, limited accessibility and sensitivesurrounding environment. Which pile type, pile driving- and waterproofing methods that are most suited forsuch conditions is different for each project. The steel core pile is more suitable for higher loads, rockstructures in incline and when verification of load capacity is not needed. At the same time the steel pipepile is more suited when the underlying rock bed is far below ground level, where you would need manypile elements and joints. In addition, the steel pipe pile is suitable for buildings with a complex loaddistribution, where a greater number of piles with lower load capacities is needed in order to satisfy this.The best pile driving method for drilling in sensitive environment is the water equipped down-the-hole(DTH) drill. This drilling method is gentle to surrounding piles in existing building.In order to minimise the risk of water penetration and then expand the life span of the construction, use ofa combination of different waterproofing systems is to prefer when waterproofing pile heads or pilefoundations.
12
Richard, Leeland. "Spiral Welded Pipe Piles For Structures In Southeastern Louisiana." ScholarWorks@UNO, 2010. http://scholarworks.uno.edu/td/1257.
Full textAbstract:
In an effort to obtain 100-year level hurricane protection for southeastern Louisiana, the U.S. Army Corps of Engineers (USACE) has implemented design guidelines that both levees and structures shall be designed to. Historically, USACE has used concrete piles or steel H-piles as the foundations for these structures. Because of the magnitude of obtaining 100-year level hurricane protection, limited resources, and a condensed timeline, spiral welded pipe piles can be manufactured as an alternative to either the concrete piles or steel H-piles. This research will provide the necessary background for understanding pile foundations, will compare the behaviors of spiral welded pipe piles to that of other piles with respect to geotechnical concerns through a series of pile load tests, and will offer a current cost analysis. This background, testing, and cost analysis will show that spiral welded pipe piles are a viable alternative for USACE structures from a geotechnical and economic perspective.
13
Russell, Dalin Newell. "The Influence of Pile Shape and Pile Sleeves on Lateral Load Resistance." BYU ScholarsArchive, 2016. https://scholarsarchive.byu.edu/etd/6232.
Full textAbstract:
The lateral resistance of pile foundations is typically based on the performance of round piles even though other pile types are used. Due to lack of data there is a certain level of uncertainty when designing pile foundations other than round piles for lateral loading. Theoretical analyses have suggested that square sections will have more lateral resistance due to the increased side shear resistance, no test results have been available to substantiate the contention. Full-scale lateral load tests involving pile shapes such as circular, circular wrapped with high density polyethylene sheeting, square, H, and circular with a corrugated metal sleeve have been performed considering the influence of soil-pile interaction on lateral load resistance. The load test results, which can be summarized as a p-y curve, show higher soil resistance from the H and square sections after accounting for differences in the moment of inertia for the different pile sections. The increased soil resistance can generally be accounted for using a p-multiplier approach with a value of approximately 1.25 for square or 1.2 for H piles relative to circular piles. It has been determined that high density polyethylene sheeting provides little if any reduction in the lateral resistance when wrapped around a circular pile. Circular piles with a corrugated metal sleeve respond to lateral loading with higher values of lateral resistance than independent circular piles in the same soil.
14
Bordas, Mariano. "Possibilités offertes par l'utilisation simultanée des méthodes PIXE, Particle Induced X-ray Emission, et PIGE, Particle Induced Gamma-ray Emission, en analyse élémentaire." Grenoble 2 : ANRT, 1988. http://catalogue.bnf.fr/ark:/12148/cb376120482.
Full text
15
Bordas, Mariano. "Possibilites offertes par l'utilisation simultanee des methodes pixe (particle induces x-ray emission) et pige (particle induced gamma-ray emission) en analyse elementaire." Université Louis Pasteur (Strasbourg) (1971-2008), 1988. http://www.theses.fr/1988STR13009.
Full text
16
Lara-Chavez, Alejandra M. "Somatic embryogenesis in southern and tropical pine species: Loblolly pine (Pinus taeda), Longleaf pine (P. palustris) and Oocarpa pine (P. oocarpa)." Diss., Virginia Tech, 2010. http://hdl.handle.net/10919/77176.
Full textAbstract:
The focus of the current project was to establish an improved and reliable protocol for somatic embryogenesis in 1) Pinus taeda and Pinus palustris; pine species of high value for commercial applications and germplasm conservation supported through breeding programs at The Virginia Department of Forestry (Chapter III); and 2) Pinus oocarpa; an economically important pine species in the southern half of Mexico and Central America (Chapter IV). In addition, 3) the study of the gene expression analysis of developmental stages of both somatic and zygotic embryos of P. taeda was compared to assess developmental fidelity at the molecular level (Chapter V). By testing four basal media combined with different plant growth regulator combinations, we have established stable embryogenic cultures from high value families of P. taeda and P. palustris using the tissue culture medium 1218 (Pullman et al 2005) in combination with an auxin:citokinin ratio at 10:5 (molar). However, optimization of the protocols for the maturation and further conversion of somatic embryos to seedlings requires further work. For P. oocarpa, we hypothesized that somatic embryo induction may be possible by mimicking natural seed-embryo developmental conditions, and a new tissue culture medium, based on the mineral content of the seed nutritive tissue (megagametophyte), was formulated. The novel culture medium (PO) was tested in combination with different plant growth regulator concentrations for the initiation of somatic embryogenesis from fresh collections of P. oocarpa immature zygotic embryos. Additionally, the established embryogenic cultures were able to mature and germinate, to our knowledge resulting in the first report of the production of P. oocarpa plantlets through somatic embryogenesis. PO medium also has the potential to be used successfully for other tropical pine species which today suffer from suboptimal somatic embryogenesis protocols. The fundamental study of molecular regulation of embryo development showed that under the current maturation conditions, P. taeda somatic embryos were temporally similar in gene expression to zygotic embryos of the same species. However, potentially important differences were found and results could potentially explain the low germination success during somatic embryogenesis. More research is still needed to further explore the natural environment of developing seed embryos to improve the somatic embryogenesis protocols and to enable full integration of this clonal propagation method into the breeding programs for pines.Ph. D.
17
Lituma, Portocarrero Luis. "Pias Voluntades." Pontificia Universidad Católica del Perú, 2016. http://repositorio.pucp.edu.pe/index/handle/123456789/116114.
Full text
18
Olofsson, Filip. "Pite'-maffian." Thesis, Kungl. Musikhögskolan, Institutionen för jazz, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kmh:diva-2411.
Full textAbstract:
I dett arbete skriver jag om arbetet och processen kring mitt examensarbete som var en konsert på skolan till vilken jag skrivit all musik. Ämnen som behandlas är b.la hur det är att spela med syskon och hur det är att leda ett band med två mycket erfarna musiker. Stort fokus ligger på självkritik då jag tycker det är någoting som oftare borde tas upp.Kompositioner:The Pilot (Filip Olofsson) Pledge drive (Filip Olofsson) The keys (Filip Olofsson) Pitch (Filip Olofsson) The stakeout (Filip Olofsson) The Opposite (Filip Olofsson) Extra: Giant steps (John Coltrane) Medverkande:Robert Nordmark - saxofon, Petter Olofsson - bas, Filip Olofsson - trummor
19
Gross, Donovan. "Mountain Pine Beetle Fecundity and Offspring Size Differ Among Lodgepole Pine and Whitebark Pine Hosts." DigitalCommons@USU, 2008. https://digitalcommons.usu.edu/etd/34.
Full textAbstract:
Whitebark pine (Pinus albicaulis Engelmann) is a treeline species in the central Rocky Mountains. Its occupation of high elevations previously protected whitebark pine from long-term mountain pine beetle outbreaks. The mountain pine beetle, however, is currently reaching outbreaks of record magnitude in high-elevation whitebark pine. We used a factorial laboratory experiment to compare mountain pine beetle (Dendroctonus ponderosae Hopkins) life history characteristics between a typical host, lodgepole pine (Pinus contorta Engelmann), and whitebark pine. We tested the effects of natal host and brood host on beetle fecundity, offspring size, and brood sex-ratio. We reared mountain pine beetles from whitebark pine and from lodgepole pine, and infested half of them into their natal host and half into the other host. Fecundity was greater overall in lodgepole pine brood hosts. Among lodgepole brood hosts, beetles from whitebark pine had greater fecundity. Fecundity was also significantly related to phloem thickness, which was greater in lodgepole pine. Offspring were larger from whitebark brood hosts than from lodgepole, regardless of their parents’ natal host. Finally, sex-ratio was closer to 1:1 in lodgepole than in whitebark brood hosts. We conclude that host species affects life history of mountain pine beetle with consequences for individual beetle fitness.
20
Kamil, Insan. "Macro-element modeling for single pile and pile group." Thesis, Lille 1, 2019. http://www.theses.fr/2019LIL1I082.
Full textAbstract:
La méthode proposée présente une analyse simple de l’interaction sol-structure (SSI) pour le calcul des pieux sous sollicitation axiales, transversales et groupe de pieux. Un modèle basé sur le concept de macroéléments, s'inspire de Abboud 2017, est développé pour étudier le SSI en prenant en compte les différentes non-linéarités. Sa formulation est basée sur la théorie de l'élastoplasticité et s'inspire des normes européennes (Eurocodes 7 et 8). Les différents paramètres étant définis à partir d'essais en laboratoire ou in situ, ou à partir de simulations numériques dans des conditions statiques. Ce modèle réduit les coûts de calcul car les non-linéarités liées au SSI sont concentrées dans des points particuliers du modèle de calcul. L'avantage du macroélément réside dans sa formulation en forces et déplacements, ce qui facilite son utilisation pour la justification des fondations (capacité portante, glissement, détachement, tassement, translation, distorsions et rotation). De plus, ce macroélément est implémenté dans le cadre de la méthode des éléments finis en tant que fish function dans Flac3D. Cet outil est capable de simuler le SSI du chargé monotone appliqué verticalement et transversalement au pieu. Le modèle proposé a été validé par les résultats des tests de charge de pieu, la méthode des courbes de transfert (basée sur la méthode de Frank et Zhao) et la programmation informatique (conventionnels Flac3D et Pilate). L'approche réussit avec une bonne performance. De plus, l'efficacité et l'application pratique des cette methode dans l'analyse par éléments finis de calcul sont réalisables pour un pieu et un groupe de pieuxThe proposed method presents a simple analysis of Soil-Structure Interaction (SSI) for deep foundation under static load that is applied for single pile and pile group. A model based on macroelement concept, inspired from Abboud 2017, is developed to study the SSI taking into account the different nonlinearities. Its formulation is based on the theory of elastoplasticity and is inspired by European standards (Eurocodes 7 and 8). Wherein, the different parameters are defined from laboratory or in situ tests, or from numerical simulations under static conditions. This model reduces computational costs because the nonlinearities related to the SSI are concentrated in particular points of the computation model. The advantage of macroelement lies in its formulation in forces and displacements, which facilitates its use for the justification of the foundations (bearing capacity, sliding, detachment, settlements, translations, distortions and rotations). Furthermore, this macroelement is implemented in a Finite Element Method framework as a fish function in Flac3D. This tool is capable of simulating the SSI in the monotonic loaded pile. The proposed model has been validated with pile load test results, load transfer method (based on Frank and Zhao method) and computer programming (conventional Flac3D and Pilate). The approach succeeds with a good performance. Additionally, the efficiency and practical application of this method in the computation finite-element analysis are feasible for Single Pile and Pile Group
21
Gerard, Mathias. "Étude des interactions pile/système en vue de l'optimisation d'un générateur pile à combustible : -interactions cœur de pile/compresseur- -interactions cœur de pile/convertisseur-." Phd thesis, Université de Franche-Comté, 2010. http://tel.archives-ouvertes.fr/tel-00618808.
Full textAbstract:
La pile à combustible PEMFC est un convertisseur d'énergie qui présente des avantages indéniables pour faire partie des solutions mises en œuvre pour assurer un mixte énergétique décarbonné. Les nombreux auxiliaires du système de la pile génèrent des perturbations qui sont responsables directement ou indirectement des conditions défavorables sur le cœur de pile. Les performances et durée de vie de la pile peuvent être impactées. Dans l'objectif d'améliorer la co-conception de la pile avec son système, les interactions entre deux groupes du système et la pile sont étudiées dans ce travail : les interactions entre le groupe air et le cœur de pile. En particulier, l'étude s'est focalisée sur l'impact d'un fonctionnement en sous stœchiométrie en oxygène sur la performance et la durabilité de la pile et sur l'évolution des conditions locales du cœur de pile. Le couplage des différents essais expérimentaux (mesures de densité de courant, tests de vieillissement, études post-mortem) avec le modèle dynamique 2D a permis de mettre en évidence différentes zones de fonctionnement dans la pile. En effet, en entrée cathodique, durant un appauvrissement en oxygène, l'augmentation de la densité de courant peut devenir très importante impliquant une modification des conditions locales qui peuvent être très néfastes pour la pile. les interactions entre le convertisseur statique électrique et le cœur de pile. Plus particulièrement, les conséquences des oscillations de courant hautes fréquences générées par le convertisseur DC/DC sur la durabilité de la pile ont été étudiées. Des essais spécifiques de vieillissement longue durée ont permis de mettre en évidence une interaction entre les oscillations de courant et les dégradations réversibles de la pile.
22
Wallertz, Kristina. "Pine weevil feeding in Scots pine and Norway spruce regenerations /." Alnarp : Southern Swedish Forest Research Centre, Swedish University of Agricultural Sciences, 2009. http://epsilon.slu.se/200960.pdf.
Full text
23
DeGomez, Tom, and Deborah Young. "Pine Bark Beetles." College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2009. http://hdl.handle.net/10150/146729.
Full text
24
DeGomez, Tom, and Deborah Young. "Pine Bark Beetles." College of Agriculture, University of Arizona (Tucson, AZ), 2015. http://hdl.handle.net/10150/550373.
Full textAbstract:
Revised; Originally Published 20024 pp.
Pine bark beetles in Arizona are generally of the genus Ips or Dendroctonus. Fading foliage in the tree is often the first sign of a beetle attack. Prevention is best practiced since control is not possible once the beetles have successfully colonized the tree. Colonization is dependent upon trees being in a vulnerable condition caused by stress from various agents and site conditions.
25
McCormick, John T. II. "Jack Pine Scraggly." Miami University / OhioLINK, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=miami1091500019.
Full text
26
Pam, Hoat Joen. "Seismic performance of prestressed concrete piles and pile-pile cap connections." Thesis, University of Canterbury. Civil Engineering, 1987. http://hdl.handle.net/10092/7634.
Full textAbstract:
The performance, strength and ductility of prestressed concrete piles, and their connection to pile caps, subjected to severe seismic loading are investigated in this thesis.
Knowledge of the strength and ductility of the pile within its embedded length in the foundation material is of importance due to the large deformations which can occur during an earthquake, particularly at the interface of hard and soft layers of foundation material. Connection details are of interest since high moments, shears and axial forces need to be transferred to pile caps during earthquake loading.
Two series of tests of piles and their connections, and accompanying analyses, were conducted. Design tables and charts were derived.
The first test series consisted of six full scale octagonal prestressed concrete piles, confined spirally with either Grade 275 steel or hard drawn (Grade 485) steel wire and having various confinement levels, tested under axial load and cyclic flexure. Results of the theoretical analysis were compared with the experimental data. It was found that properly detailed prestressed concrete piles without additional nonprestressed longitudinal steel can sustain large displacement ductility factors without losing their lateral load carrying capacity significantly if confined according to full ductility.
The second test series consisted of six full scale octagonal piles connected to full scale reinforced pile caps. The piles were either fully or partially prestressed. Three types of pile to pile cap connection were investigated, namely the precast embedded type, the stripped pile head type, and the type where steel dowel bars are used as the connection device. Theoretical analyses were used to compare the experimental data. The connection details investigated were found to give satisfactory performance.
Finally, tables and charts obtained for the pile properties are presented for design purposes. The design tables are used to assess the enhancement factors of pile cross sections within the length or at the interface of the connection at the pile cap. The design charts are used to calculate the yield curvatures as well as the available curvatures and available curvature ductility factors. Recommendations for future research are proposed to complement the work already done up to this stage.
27
Pike, Stefan. "Experimental investigation of leakage-induced pipe erosion outside of pipe leaks." Master's thesis, University of Cape Town, 2016. http://hdl.handle.net/11427/20518.
Full textAbstract:
The problem of water loss from water distribution systems is an issue that faces municipalities worldwide. A large proportion of water loss is a result of leakage. With increasing water scarcity across the globe, it is imperative to conserve water resources, and hence reduce leakage in water distribution systems as best we can. Leaks develop in various different forms, and they form in pipes of all materials. It has been observed in numerous cases around the world that pipe material has been removed from the pipe surfaces adjacent to leaks in excavated failed water distribution pipe specimens. It was proposed by various researchers that this pipe material was being removed as a result of abrasive soil action caused by the pipe leak itself. When pressurised water distribution pipes fail, they emit high velocity jets of water into the surrounding soil bed. Research has shown that high velocity jets of water entering a granular soil bed have the ability to fluidise the bed, allowing the granular particles to move freely. This fluidisation mechanism is known as internal fluidisation. The concept of internal fluidisation offers an explanation for the erosion of pipe material adjacent to pipe leaks. In this study, the removal of pipe material adjacent to leaks due to internal fluidisation has been termed "leakage-induced pipe erosion." This phenomenon has received minimal attention from researchers in the past. Leakage-induced pipe erosion has the potential to aggravate small existing leaks. There are two main implications of aggravating small leaks; firstly, where water authorities do not utilise active leak detection programmes, aggravating the initial leak conditions of small leaks can result in increased long term water losses. Secondly, in water distribution systems where the water authority does implement active leak detection programmes, aggravating small leaks increases the probability of finding and repairing them. This aim of this study was to experimentally investigate the influence of various factors on the leakage-induced erosion process. Five main factors were investigated, namely bedding material grain size, cover depth, leakage flow rate, initial leak orientation and pipe material. An experimental setup was designed and manufactured in order to provide a controlled environment in which to investigate the factors affecting leakage-induced pipe erosion.
28
Oneil, Elaine E. "Developing stand density thresholds to address mountain pine beetle susceptibility in eastern Washington forests /." Thesis, Connect to this title online; UW restricted, 2006. http://hdl.handle.net/1773/5536.
Full text
29
Kite, Matthew J. S. "Computational modelling of clay pipe extrusion." Thesis, Available from the University of Aberdeen Library and Historic Collections Digital Resources. Online version available for University members only until June 9, 2014, 2009. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?application=DIGITOOL-3&owner=resourcediscovery&custom_att_2=simple_viewer&pid=25966.
Full text
30
Acharya, Tanka Prasad Somers Greg Lynn. "Prediction of distribution for total height and crown ratio using normal versus other distributions." Auburn, Ala., 2006. http://repo.lib.auburn.edu/2006%20Fall/Theses/ACHARYA_TANKA_3.pdf.
Full text
31
Powell, David B. "A post-harvest evaluation of mechanized thinning in natural loblolly pine in the coastal plain of Arkansas." Thesis, This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-09192009-040300/.
Full text
32
Bockino, Nancy Karin. "Interactions of white pine blister rust, host species, and mountain pine beetle in whitebark pine ecosystems in the Greater Yellowstone." Laramie, Wyo. : University of Wyoming, 2008. http://proquest.umi.com/pqdweb?did=1594498141&sid=3&Fmt=2&clientId=18949&RQT=309&VName=PQD.
Full text
33
ESPOSITO, RICARDO GUREVITZ CUNHA. "NUMERICAL MODELLING OF PILE INSTALLATION AND PILE LOAD TEST USING DISCRETE ELEMENTS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2015. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=26592@1.
Full textAbstract:
PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIROCOORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
PROGRAMA DE EXCELENCIA ACADEMICA
As alterações no solo decorrentes de um elemento de fundação profunda e seus desempenhos sob a aplicação de carga axial são processos há muito tempo estudados na engenharia civil. Diversos fatores como, método de instalação utilizado, formato da estaca, interações solo-estrutura, mecanismos de transferências de carga, movimentação do solo e alterações na compressibilidade e tensões do solo adjacente, apresentam desafios importantes que ainda não foram totalmente compreendidos nos fenômenos de penetração e capacidade de suporte em estacas. Diversos avanços foram realizados ao longo das últimas décadas para se investigar estes comportamentos, a partir procedimentos experimentais e novas formas de instrumentação, assim como ferramentas numéricas sofisticadas com o emprego de complexos modelos constitutivos em elementos finitos. Apesar destes avanços, a modelagem numérica dos processos citados, com todas as suas complexidades, ainda encontra alguns desafios. Devido a facilidade em lidar com simulações de grandes deformações e de captar o comportamento dilatante e nãolinear de solos granulares, o Método dos Elementos Discretos apresenta uma excelente ferramenta para investigar estes processos, sem grandes complicações. O presente trabalho procurou avaliar os comportamentos obtidos a partir de diferentes processos de instalação da estaca e seus efeitos nos resultados da prova de carga estática em solos granulares. As alterações de tensão e deslocamento foram avaliadas nos diferentes modelos e discutindo sobre uma metodologia básica para obter correspondências qualitativas e quantitativas com os diferentes comportamentos de campo e laboratório. Para este estudo foram utilizados os programas PFC, na versão 2D, e o programa UDEC, da Itasca co.
The disturbances experienced by the soil owing to the load applied to a deep foundation and its relative behavior consist of long time studied phenomena in civil engineering. Several factors such as the installation methods, the pile geometry, the interactions between soil and structure, the load-transfer mechanisms, the soil movements and the disturbances in the stress and compressibility fields present major challenges that have not yet been completely understood. Numerous advances have been observed throw-out the last decades, in order to investigate these behaviors starting from the different pile instrumentations, the use of calibration cameras and centrifuges and most recently the measurement of the stress and strain fields inside the soil mass in model tanks. Despite the advances the numerical modelling of those processes still faces major challenges. Due to simplified approach used by the Discrete Element Method to simulate large deformation and the dilant non-linear behavior of granular soils, it presents as an excellent tool to investigate these processes without further complications. The present work proposed to evaluate the different behaviors obtained with the variations of installation methods investigated as well as their effects in the results of the Pile Load Test. The disturbances were also evaluated in the different models considered and a basic method to achieve qualitative and quantitative comparisons was discussed. These studies were made possible with the help of the PFC2D and UDEC programs developed by Itasca co.
34
Adams, Thomas P. "Reconstructing Scotland's pine forests." Thesis, University of Edinburgh, 2010. http://hdl.handle.net/1842/4730.
Full textAbstract:
The Caledonian pinewoods are a habitat of crucial environmental and cultural importance, and the sole home of many rare species. However, they have seen steady decline in recent centuries, through the establishment of hunting estates and forestry plantations. A recent trend in management is the attempted transformation of existing plantations (dense communities with a regular spatial structure and low variance in size and age) towards a state mimicking the perceived natural condition, which has a lower density, irregular spatial pattern, high variance in size and age. This presents a problem for traditional forestry practices, which were conceived primarily with “even-aged” plantation populations in mind. The shift towards management of an uneven-aged structure requires a more in-depth consideration of individual trees’ lifecycles and their effect upon long-term population dynamics. In recent years, great advances in computational and mathematical models for spatially interacting populations have been made. However, certain complications have prevented them from being utilised to their full potential for the purposes of forest management. Forest communities are not only spatially structured; the size of each tree plays a role in its ability to acquire resources for growth and survival. Existing models of population dynamics are discussed, and their extension to incorporate both size- and spatially- structured interactions is presented. The key aspects of populations’ structural development are studied. Data from both plantation and semi-natural Scots Pine stands in Scotland allow parameterisation of a stochastic individual-based model, which in turn provides insights into the behaviour of real populations, and the importance of spatial effects and heterogeneity in individuals. A partial differential equation (moment) approximation to the stochastic model is presented. While this is analytically intractable, numerical integration and heuristic analysis of the equations enable clearer identification of the drivers of population structure. Many results are concordant with existing models of both qualitative forest stand development and theoretical dynamics of spatially-structured populations, while others are specific to joint size-space structure. This deeper understanding of the population dynamics allows robust recommendations for diverse uneven-aged stand management objectives to be made. Approaches to accelerating the transformation of plantation stands towards a “natural” state (using two key operations: thinning – removal of trees, and planting) are investigated. Finally, approaches to so-called “continuous cover forestry” – the practice of maintaining a quasi-natural state while also obtaining economic value from a forest – are also considered. In both cases, the model’s simplicity enables clearer conclusions than would be possible using other approaches.
35
England, Melvin Gerrard. "A pile behaviour model." Thesis, Imperial College London, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.311976.
Full text
36
Barkley, Clayde Betts Mikel Olay Anthony. "Indirect pipe pressure measurement /." Click here to view, 2009. http://digitalcommons.calpoly.edu/mesp/12.
Full textAbstract:
Thesis (B.S.)--California Polytechnic State University, 2009.Project advisor: Jim Meagher. Title from PDF title page; viewed on Jan. 20, 2010. Includes bibliographical references. Also available on microfiche.
37
Pineda-Vargas, Carlos A. "Thick target pixe analysis." Doctoral thesis, University of Cape Town, 1993. http://hdl.handle.net/11427/16005.
Full textAbstract:
Bibliography: p. 211-221.The evaluation of the physical parameters governing the X-ray yield production in thick targets by charged particles was investigated and matrix correction factors (MCF) were calculated for a wide variety of materials including values for all pure non-gaseous elements or their compounds for the Kα and Lα X-ray lines. These factors were calculated for 1, 2, 3 and 4 MeV proton bombarding energies. A new methodology named 'common matrix type' (CMT) was developed for the determination of trace element concentrations in carbon-rich materials, such as most biological materials, with unknown matrix composition. A universal set of matrix correction factors (MCF) values for these materials was established for trace elements with Z ≥ 19 and irradiations with proton energies in the range of 1 to 4 MeV. A similar methodology was developed for silicon-rich and calcium-rich materials where the main components, Al, Si and Ca do not vary appreciably in their concentrations. CMT methodologies were applied successfully for the determination of trace elemental concentrations in a wide variety of thick target materials, which included archaeological cultural materials, biological tissues and geological ores. The technique of correspondence analysis was used for the statistical analysis of the extended data matrix generated in most of the applications. This technique of interpretation of multielemental data proved to be a valuable tool. Two modes of PIXE application, macro-mode and micro-mode, were evaluated at different ion bombarding energies ranging from 1 to 85 MeV. Experimental X-ray production cross sections at 66 and 85 MeV were evaluated and found to correlate well with theory based on the plane wave Born approximation (PWBA) for the Kα and Kβ lines. It was found that the irradiation of intermediate thickness samples of geological ores by energetic protons (66 MeV) is a suitable technique for the determination of small traces of rare earth metals with detection limits for analysis expected to be below the μg.g-1 range. The fact that energetic protons can be used means that no need for matrix correction is necessary. Micro-PIXE with low energy protons was found suitable for the determination of small traces of metals in human kidney stones and for the study of interrelationships between trace element concentrations with time of stone formation, in stones excreted from a single patient.
38
Cassidy, Richard. "The 1259 pipe roll." Thesis, King's College London (University of London), 2012. https://kclpure.kcl.ac.uk/portal/en/theses/the-1259-pipe-roll(5e71288c-062d-4312-960f-10feccc4c194).html.
Full textAbstract:
The 1259 pipe roll contains accounts for most of the counties of England, covering the first full year of government by the reforming council set up by the baronial coup of 1258. The transcript of the roll makes up the bulk of this thesis. An unusually wide range of financial records, also mostly unpublished, survives from the years around 1259. These records are used together with the pipe roll to describe government finances and to show that the machinery of government continued to function successfully in the early years of the reform period. The thesis begins with a description of the editorial conventions used, and a discussion of the value of such transcripts. The financial information contained in the roll is extracted and analysed, to show the sources of government revenue, and how it was spent in the counties. The relationship between the central government and the sheriffs who administered the counties was changed radically in 1258, with the new sheriffs appointed by the reforming council as custodians, who were to account for the traditional income from the counties. These sheriffs’ accounts provide information about the customary payments and local courts in the counties which is not usually available. The income produced by the sheriffs and by the manors of the royal demesne over the period from 1241 to 1259 is compared, to show how the sheriffs squeezed additional revenue from the counties in the 1250s, and how the demesne continued to make a significant contribution to royal resources. The efforts of the reformers to control the financial administration and to reform Exchequer procedures had some success between 1258 and 1261. The financial collapse of the mid-1260s accompanied the struggle for control of the government and the drift towards civil war.
39
Kazma, Jad. "EFFECTS OF BEDDING VOID ON INTERNAL MOMENT INCREASE IN CONCRETE PIPES." Master's thesis, University of Central Florida, 2005. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2950.
Full textAbstract:
Large diameter concrete pipes have been used in many areas of central Florida to carry pressured sewage flow. These pipes have been typically located at six feet below finished roadway elevation, and ranges in diameter from thirty six to sixty inches. The water table is typically located at shallow depth below finished roadway elevation, and generally fluctuates between five to ten feet depending on the relative roadway elevation to mean sea level. These pipes are under pressure when carrying the sewage flow, but return to normal atmospheric pressures when the flow stops. Since the water table encases most of the pipe circumference, no leaks is developed from the water table to the pipe when the pipe is under pressure. Once the pressure in the pipes returns to zero, the water starts seeping into the pipe while washing the subgrade with it into the pipe's interior. The subgrade washes into the pipe at the joint inverts between adjacent pieces of the pipe, since the invert is where the most tension exists in the joint under the weight of the soil and traffic loading above the pipe, making it the most probable location where a gap in the joint would form. This would cause the origination of a small void under the pipe, which creates pressure redistribution in the subgrade reaction under the pipe. As the void develops in the middle third of the bedding under the invert, pressure redistribution occurs to the outer two thirds of the bedding. As the stress increases in the outer portions of the bedding, more subgrade material is washed into the pipe when it is not under pressure, making the void larger. As the void becomes large, the moment in the pipe is greatly increased, and therefore the gap in the joint is increased due to the tension increase at the bottom of the pipe. More material is allowed into the pipe, and the void becomes deeper as fewer restrictions are encountered between the water table and the empty pipe. As the pipe becomes pressurized, more subgrade material is disturbed by the leak from the inside of the pipe to the outside, and void is constantly generated. The void then leads to the continuous settlement of the roadway. It is intended by this study to model the stresses in the subgrade around the pipe using a finite element software to determine the effects of void in the pipe's bedding on the stress around the pipe's outer perimeter. The stresses calculated as a result of the void will then be used in determining the increase in internal moment created in the pipe as the void is generated and became larger and deeper. Average stresses on the top and bottom of the pipe were calculated due to the soil profile dead load and live load caused by loading the soil profile with one and two HS-20 trucks. The average stresses were recalculated after the addition of void in the pipe bedding. The void width and depth were varied to come up with the case that would generate the highest unbalanced load on the pipe. The average bottom stress was subtracted from the average top stress to determine the unbalanced load on the pipe that would cause an internal moment in the pipe. At the most critical case, a forty kilo pounds per foot moment was caused by the existence of the void under the sixty inch diameter pipe used in the model. Such a moment is large to be resisted by either the pipe alone or the pipe reinforced by an additional structural support, unless such support is accompanied by void decrease and a mean to stop the subgrade from eroding into the pipe.M.S.C.E.
Department of Civil and Environmental Engineering
Engineering and Computer Science
Civil Engineering
40
Guillement, Claire. "Pile – Soil Interaction during Vibratory Sheet Pile Driving : a Full Scale Field Study." Thesis, KTH, Jord- och bergmekanik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-136578.
Full textAbstract:
Urban construction sites require strict control of their environmental impact, which, for vibratory sheet pile driving, can include damage to nearby structures due to ground vibrations. However, the lack of knowledge concerning the generation of soil vibrations makes the prediction of ground vibration levels difficult. This MSc. thesis in particular, focuses on a crucial link in the vibration transfer chain: the sheet pile – soil interface, which is also one of the least documented. The aim of this thesis is first, to carry out a full-scale field test consisting in the monitoring of sheet pile and ground vibrations during sheet pile vibratory driving. And second, to analyze a selected portion of the collected data with focus on the sheet pile – soil vibration transfer. Both aspects of the thesis work aim, more generally, to contribute to the understanding of ground vibration generation under vibratory sheet pile driving. The full-scale field study was performed in Solna in May 2013. It consisted in the vibratory driving of seven sheet piles, out of which three were fitted with accelerometers. During the driving, ground vibrations were measured by accelerometers, the closest ones placed only 0.5 m from the sheet pile line. The design and installation of the soil instrumentation was innovative in as much as accelerometers were not only set on the ground surface but also at three different depths (~ 3 m, 5 m and 6 m). The analysis presented in this thesis is primarily a comparison between sheet pile vibrations and ground vibrations measured 0.5 m from the sheet pile line. The principal aspects considered in the comparison are: the influence of penetration through different soil layers, the sheet pile – soil vibration transfer efficiency, the frequency content of sheet pile and soil vibrations, and differences between toe- and shaft-generated vibrations. The main conclusions from this study are: Most of the vibration loss occurs in the near field: 90-99% of the sheet pile vibration magnitude was dispersed within 0.5 m from the driven sheet pile. Moreover, the sheet pile – soil vibration transfer efficiency was reduced for higher sheet pile acceleration levels and higher frequencies. The soil characteristics strongly influence the sheet pile vibration levels. A clear distinction could be made between "smooth" and "hard" driving, the latter being associated with an impact situation at the sheet pile toe. The focus of ground vibration studies should not only be the vertical vibrations. Indeed, the ground vibrations’ horizontal component was found to be of the same or even higher magnitude than the vertical component.
41
Dean, Diana K. "Host utilization by the mountain pine beetle, Dendroctonus ponderosae Hopkins (Coleoptera: Scolytidae), in mixed stands of limber pine, Pinus flexilis James, and lodgepole pine, Pinus contorta latifolia Engelmann." Laramie, Wyo. : University of Wyoming, 2007. http://proquest.umi.com/pqdweb?did=1404342031&sid=1&Fmt=2&clientId=18949&RQT=309&VName=PQD.
Full text
42
Fries, Megan L. "Relationships between Rooting Restrictions, Radial Growth, and Drought Stress with White Pine (Pinus strobus) Decline in Southern Maine." Fogler Library, University of Maine, 2002. http://www.library.umaine.edu/theses/pdf/FriesML2002.pdf.
Full text
43
Gama, Sophie. "Evénements métallogéniques à W-Bi (Au) à 305 Ma en Châtaigneraie du Cantal : apport d'une analyse multi-spectrométrique (micro PIXE-PIGE et Raman) des minéraux et des fluides occlus à l'identification des sources de fluides hydrothermaux." Phd thesis, Université d'Orléans, 2000. http://tel.archives-ouvertes.fr/tel-00002404.
Full textAbstract:
Le district de la Châtaigneraie comporte deux mines de W de type filonien encaissées dans les micaschistes au contact des granites. Afin de contraindre la source de ces minéralisations, des analyses ponctuelles d'éléments traces dans des inclusions fluides et minéraux de la paragenèse minéralisée primaire ont été entreprises par PIXE-PIGE et comparées aux analyses des minéraux et des fluides des réservoirs métamorphique et leucogranitique, sources potentielles des métaux.L'emploi d'un "funny filter" lors de l'analyse PIXE permet la détection des éléments K à U. Ce travail illustre que cette méthode est absolue à condition que la géométrie du dispositif analytique soit connue précisément. La paragenèse primaire à W possède une signature d'éléments traces d'affinité leucogranitique (F, Mn, Zn, Ga, As, Nb, Sn, Ta, W, Bi). L'arsenic apparaît écouplé des leucogranites et contrôlé par les micaschistes encaissants : cet élément est détecté dans les fluides du métamorphisme barrovien (¡Ö340 Ma) et les minéraux et fluides du stade à W (¡Ö305 Ma). Les caisses filoniennes subissent une fracturation en tension, une intense dissolution du quartz, un dépôt géodique
de pyrite et muscovite, une paragenèse à bismuth natif, bismuthinite, molybdénite, chalcopyrite, covellite, tennantite, waylandite, cannonite, sidérite et chlorite. Des tourmalinites massives stériles se développent, en veines ou en remplacement, de façon contemporaine. Les tourmalinites de La Granière présentent du quartz cataclastique avec de nombreuses microinclusions de biotite, muscovite, feldspath potassique, ilménite, zircon, monazite et xénotime. Le cortège de traces de ce stade est caractérisé par Fe, Mn, Cu, Zn, Ti, Cr, Sc, V, Se, Zr, Ag, Cd, Ba, Sr, Sb, Hf, Y, La, Ce et Th.
Les fluides associés sont aquo-carboniques, riches en K, Ca, métaux de base. Le caractère de ce fluide, alumino-potassique, sous-saturé en silice, phosphaté, chargé en métaux lourds et de transition (y compris Cr et Sc), REE, LILE et HFSE, suggère une affinité avec des fluides métasomatiques du manteau, ce que confirment la géochimie, la minéralogie et la texture d'un lamprophyre sécant sur une veine minéralisée. La chimie des minéraux et des fluides indique une ébullition généralisée des
solutions à ce stade en liaison avec le flux thermique élevé et la remontée rapide du bâti en fin d'orogenèse.
44
Cedervind, Jan. "Impact of pine looper defoliation in Scots pine : secondary attack by pine shoot beetles, tree mortality, top-kill, growth losses, and foliage recovery /." Uppsala : Dept. of Entomology, Swedish Univ. of Agricultural Sciences, 2003. http://epsilon.slu.se/s297.pdf.
Full text
45
Deckner, Fanny. "Ground vibrations due to pile and sheet pile driving : influencing factors, predictions and measurements." Licentiate thesis, KTH, Jord- och bergmekanik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-119291.
Full textAbstract:
Ground vibrations due to pile driving are part of a complex process. Vibration is generated from the pile driver to the pile. As the pile interacts with the surrounding soil, vibrations are transferred at the pile-soil interface. The vibration propagates through the ground and interacts with structures, both above ground and underground. The vibration continues into the structure where it may disturb occupants and/or damage the structure. In this thesis the study of the vibration transfer process due to pile driving is limited to the vibration source and the wave propagation in the soil. Vibration transmission to adjacent buildings and structures is not studied. However, impact of vibrations on buildings is briefly discussed in the literature study. It is important to accurately predict the magnitude of ground vibrations that result from pile driving in urban areas, both over- and underestimated vibration levels lead to increased costs. A lot of research has been performed within this field of knowledge, but a reliable and acknowledged prediction model for vibrations induced by pile or sheet pile driving is still needed. The objective of the research project is to increase the knowledge and understanding in the field of ground vibrations due to impact and vibratory driving of piles and sheet piles. This research project also aims to develop a reliable prediction model that can be used by practising engineers to estimate vibration due to pile driving. This licentiate thesis presents the first part of the research project and aims to increase the knowledge and understanding of the subject and to form a basis for continued research work. The most important findings and conclusions from this study are: The main factors influencing vibrations due to pile and sheet pile driving are; (1) the vibrations transferred from the pile to the soil, (2) the geotechnical conditions at the site and (3) the distance from the source. The vibrations transmitted from the pile to the soil depend on the vibrations transferred to the pile from the hammer, the pile-soil interaction and the wave propagation and attenuation in the plastic/elasto-plastic zone closest to the pile. There is today no prediction model that fulfils the criteria of the “perfect” prediction model; reliable but yet easy to apply. Future research should study the transfer of vibrations at the pile-soil interface, including the generation of a plastic/elasto-plastic zone in the area closest to the pile and how that affects the transfer of vibrations from the pile to the soil.Markvibrationer på grund av pålning är del av en komplex process. Vibrationer genereras från pålmaskinen till pålen. När pålen kommer i kontakt med den omgivande jorden överförs vibrationer mellan påle och jord. Vibrationerna fortplantar sig som vågor genom marken och träffar byggnader och andra konstruktioner, både ovan och under jord. Vibrationerna fortsätter in i byggnaden där de kan orsaka störningar eller skador. I denna avhandling begränsas studien av vibrationsöverföringsprocessen till vibrationskällan och vågutbredningen i jord. Vibrationsöverföringen till intilliggande byggnader eller konstruktioner har inte studerats. Påverkan av vibrationer på byggnader diskuteras dock kort i litteraturstudien. Det är viktigt att på ett tillförlitligt sätt kunna förutsäga markvibrationerna på grund av pålning i stadsmiljö, både över- och underskattade vibrationsnivåer leder till ökade kostnader. Forskning har tidigare utförts inom detta område, men en tillförlitlig och allmänt accepterad prognosmodell för vibrationer på grund av pålning eller spontning saknas fortfarande. Syftet med forskningsprojektet är att öka kunskapen och förståelsen för markvibrationer som uppkommer vid installation genom slagning eller vibrering av pålar och spont. Forskningsprojektet syftar också till att utveckla en tillförlitlig prognosmodell som kan användas av yrkesverksamma ingenjörer för att uppskatta vibrationsnivåer orsakade av pålning. Denna licentiatavhandling presenterar den första delen av forskningsprojektet och syftar till att öka kunskapen och förståelsen inom ämnesområdet samt att skapa en plattform för det fortsatta forskningsarbetet. De viktigaste resultaten och slutsatserna från denna studie är: De huvudsakliga faktorer som påverkar vibrationer orsakade av pålning är; (1) de vibrationer som överförs från källan till jorden, (2) de geotekniska förhållandena på platsen och (3) avståndet från vibrationskällan (pålen). Vibrationerna som överförs från pålen till jorden beror på de vibrationer som överförs från pålmaskinen till pålen, påle-jord interaktionen samt vågutbredning och dämpning i den plastiska/elasto-plastiska zonen som bildas närmast pålen. Det finns idag ingen prognosmodell som uppfyller kriterierna för den ”perfekta” prognosmodellen; tillförlitlig men ändå lätt att tillämpa. Framtida forskning bör undersöka överföringen av vibrationer mellan påle och jord, innefattande uppkomsten av en plastisk/elasto-plastisk zon närmast pålen och hur det påverkar vibrationsöverföringen från påle till jord.
QC 20130314
46
Chin, Victor B. L. "The dynamic response of pile-soil interfaces during pile driving and dynamic testing events." Monash University, Dept. of Civil Engineering, 2003. http://arrow.monash.edu.au/hdl/1959.1/9421.
Full text
47
Bourbour, Ajdari Elena. "Volatile Organic Compound (VOC) Emission during Cured-in-Place-Pipe (CIPP) Sewer Pipe Rehabilitation." ScholarWorks@UNO, 2016. http://scholarworks.uno.edu/td/2126.
Full textAbstract:
The maintenance or replacement of deteriorated pipes and culverts is a constant and significant concern for municipalities and transportation agencies in the United States (Donaldson and Wallingford, 2010). Trenchless technologies and especially the Cured-in-place pipe (CIPP) method have become increasingly common ways to preserve infrastructures owing to their feasibility, cost-effectiveness, and fewer social impacts (Jung and Sinha, 2007). Therefore, there is a growing need to understand the direct and indirect effects of pipeline rehabilitation activities on the environment. Nearly all past CIPP studies have focused on its mechanical properties, and its environmental impacts are poorly investigated and documented (Allouche et al. 2012). Sewer pipelines and storm-water culverts are administered by municipalities and transportation agencies who bear the responsibility for rehabilitation and renewal of these infrastructures. In consequence, they rarely allow sampling and research projects in the field due to liability issues. This is a main obstacle to conducting comprehensive, precise, and unbiased research on CIPP environmental impacts and to date, the degree of relevant health effects and related environmental impacts have remained unknown.
Numerous building indoor air contamination incidents indicate that work is needed to understand the magnitude of styrene emission from CIPP sanitary sewer repairs. The main goal of this study was to better comprehend Volatile Organic Compounds emission at three CIPP sanitary sewer installation sites in one U.S. city. Results showed that CIPP chemical emissions may be a health risk to workers and nearby building inhabitants. Additional testing and investigations regarding chemical emissions from CIPP should be commissioned to fill in the environmental and public health knowledge gaps. The acute and chronic chemical exposure risks of CIPP chemical steam constituents and styrene to sensitive populations should be further examined.
Other goals of this study were to estimate the magnitude of solid waste generated as well as the amount of certain criteria air pollutants and greenhouse gases emitted from onsite heavy equipment for both CIPP and open-cut sites in a U.S city. The results indicated that the amount of open-cut related solid waste, criteria air pollutants, and greenhouse gases were greater than those during CIPP activities. Additional work is needed to quantify pollutant emissions from CIPP and open-cut activities and consider emissions from a cradle-to-grave standpoint.
48
Ajdari, Elena Bourbour. "Volatile Organic Compound (VOC) Emission during Cured-in-Place-Pipe (CIPP) Sewer Pipe Rehabilitation." Thesis, University of New Orleans, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10291102.
Full textAbstract:
The maintenance or replacement of deteriorated pipes and culverts is a constant and significant concern for municipalities and transportation agencies in the United States (Donaldson and Wallingford, 2010). Trenchless technologies and especially the Curedin- place pipe (CIPP) method have become increasingly common ways to preserve infrastructures owing to their feasibility, cost-effectiveness, and fewer social impacts (Jung and Sinha, 2007). Therefore, there is a growing need to understand the direct and indirect effects of pipeline rehabilitation activities on the environment. Nearly all past CIPP studies have focused on its mechanical properties, and its environmental impacts are poorly investigated and documented (Allouche et al. 2012). Sewer pipelines and storm-water culverts are administered by municipalities and transportation agencies who bear the responsibility for rehabilitation and renewal of these infrastructures. In consequence, they rarely allow sampling and research projects in the field due to liability issues. This is a main obstacle to conducting comprehensive, precise, and unbiased research on CIPP environmental impacts and to date, the degree of relevant health effects and related environmental impacts have remained unknown.
Numerous building indoor air contamination incidents indicate that work is needed to understand the magnitude of styrene emission from CIPP sanitary sewer repairs. The main goal of this study was to better comprehend Volatile Organic Compounds emission at three CIPP sanitary sewer installation sites in one U.S. city. Results showed that CIPP chemical emissions may be a health risk to workers and nearby building inhabitants. Additional testing and investigations regarding chemical emissions from CIPP should be commissioned to fill in the environmental and public health knowledge gaps. The acute and chronic chemical exposure risks of CIPP chemical steam constituents and styrene to sensitive populations should be further examined.
49
Runesson, Ulf Torarind. "Considerations for early remote detection of mountain pine beetle in green-foliaged lodgepole pine." Thesis, University of British Columbia, 1991. http://hdl.handle.net/2429/31483.
Full textAbstract:
A general review of the mountain pine beetle (Dendroctonus ponderosae Hopkins) - lodgepole pine (Pinus contorta Dougl.) complex, including previous broad-band remote sensing studies aimed at early detection, is provided. The main emphasis of this thesis is on the utility of waveform analysis, based on in-situ spectroscopy, to successfully differentiate between tree canopies experiencing various degrees of stress. Damage to the tree canopies was both beetle-induced and artificial. In support of the spectroscopy, foliar analysis was performed. In addition, for comparative purposes, large-scale color-infrared photographs were both visually interpreted and measured for dye layer densities. Further, airborne digital broad-band data for the same study site were also acquired and analyzed.
Despite significant differences in pigmentation levels and moisture status, the analysis showed poor detection success with both the densitometry and visual interpretation of the color-infrared photographs. This is in sharp contrast with previous studies and is concluded to be attributed to the natural variation from year to year and from site to site. The analysis of the digital airborne data resulted in equally poor differentiation between healthy and damaged tree canopies.
The main objective of utilizing waveform analysis to take advantage of anticipated pigmentation reductions in stressed trees yielded very positive results. There were significant blue-shifts in the red-edge positions of currently attacked tree
canopies. The data suggest that in a situation where conventional detection means such as those based on photo sensitivity fail, a suitable red-edge threshold can be determined from attacked trees and used to successfully differentiate healthy from currently attacked lodgepole pines.Forestry, Faculty of
Graduate
50
Braun, David M. "Host colonization behavior of the mountain pine beetle (Dendroctonus ponderosae Hopkins) in thinned and unthinned stands of second-growth ponderosa pine (Pinus ponderosa Laws.) /." Thesis, Connect to this title online; UW restricted, 1998. http://hdl.handle.net/1773/5482.
Full text