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Dissertations / Theses on the topic 'Tree'
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1
Simmons, Mark Trevor. "Tree-grass and tree-tree interactions in a temperate savanna." Diss., Texas A&M University, 2003. http://hdl.handle.net/1969.1/1168.
Full textAbstract:
Savannas comprise over one eighth of the world's land surface with some 50 Mha in North America alone. They are productive systems supporting a high level of both faunal and floral diversity and are of increasing socioeconomic importance. The maintenance and formation of savannas have been attributed to climate, soils, herbivory and fire. However, the reasons for the coexistence of trees and the grass layer have still to be determined. These two contrasting life forms create a complex of intra- and interspecific positive, negative, and neutral interactions, few of which have been quantified. Under lower-than-average rainfall, tree effects on grasses in a Prosopis savanna in northern Texas were largely neutral with few measurable competitive or facultative effects from the tree canopy. However, grasses demonstrated increased productivity where belowground competition with neighboring trees was removed. Similarly, tree growth increased following the removal of grasses under and around individual trees, particularly on shallower soils, but only during a season of significant precipitation. Low intensity burning of grasses enhanced growth of adult trees, but patterns were inconsistent between two different sites. Moderate clipping around individual trees had no apparent effect on tree growth. Intraspecific competition between savanna trees was not evident, but may have been blurred by an extensive, lateral distribution of near-surface roots. Overall, tree intraspecific competition was neutral regardless of soil depth, suggesting lateral tree roots may be only used opportunistically. Although some competitive relationships were verified, the differences in the responses between the two years of study, and at different sites indicated that soil depth and climate may have overriding impacts on tree-grass interactions and savanna dynamics in this system.
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Okoth, Isaac Owino. "Combinatorics of oriented trees and tree-like structures." Thesis, Stellenbosch : Stellenbosch University, 2015. http://hdl.handle.net/10019.1/96860.
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Thesis (PhD)--Stellenbosch University, 2015.<br>ENGLISH ABSTRACT : In this thesis, a number of combinatorial objects are enumerated. Du and
Yin as well as Shin and Zeng (by a different approach) proved an elegant
formula for the number of labelled trees with respect to a given in degree
sequence, where each edge is oriented from a vertex of lower label towards
a vertex of higher label. We refine their result to also take the number of
sources (vertices of in degree 0) or sinks (vertices of out degree 0) into account.
We find formulas for the mean and variance of the number of sinks
or sources in these trees. We also obtain a differential equation and a functional
equation satisfied by the generating function for these trees. Analogous
results for labelled trees with two marked vertices, related to functional
digraphs, are also established.
We extend the work to count reachable vertices, sinks and leaf sinks in
these trees. Among other results, we obtain a counting formula for the number
of labelled trees on n vertices in which exactly k vertices are reachable
from a given vertex v and also the average number of vertices that are reachable
from a specified vertex in labelled trees of order n.
In this dissertation, we also enumerate certain families of set partitions
and related tree-like structures. We provide a proof for a formula that counts
connected cycle-free families of k set partitions of {1, . . . , n} satisfying a certain
coherence condition and then establish a bijection between these families and the set of labelled free k-ary cacti with a given vertex-degree distribution.
We then show that the formula also counts coloured Husimi graphs
in which there are no blocks of the same colour that are incident to one another.
We extend the work to count coloured oriented cacti and coloured
cacti.
Noncrossing trees and related tree-like structures are also considered in
this thesis. Specifically, we establish formulas for locally oriented noncrossing
trees with a given number of sources and sinks, and also with given
indegree and outdegree sequences. The work is extended to obtain the average
number of reachable vertices in these trees. We then generalise the
concept of noncrossing trees to find formulas for the number of noncrossing
Husimi graphs, cacti and oriented cacti. The study is further extended
to find formulas for the number of bicoloured noncrossing Husimi graphs
and the number of noncrossing connected cycle-free pairs of set partitions.<br>AFRIKAANSE OPSOMMING : In hierdie tesis word ’n aantal kombinatoriese objekte geenumereer. Du
en Yin asook Shin en Zeng (deur middel van ’n ander benadering) het ’n
elegante formule vir die aantal geëtiketteerde bome met betrekking tot ’n
gegewe ingangsgraadry, waar elke lyn van die nodus met die kleiner etiket
na die nodus met die groter etiket toe georiënteer word. Ons verfyn hul
resultaat deur ook die aantal bronne (nodusse met ingangsgraad 0) en putte
(nodusse met uitgangsgraad 0) in ag te neem. Ons vind formules vir die gemiddelde
en variansie van die aantal putte of bronne in hierdie bome. Ons
bepaal verder ’n differensiaalvergelyking en ’n funksionaalvergelyking wat
deur die voortbringende funksie van hierdie bome bevredig word. Analoë
resultate vir geëtiketteerde bome met twee gemerkte nodusse (wat verwant
is aan funksionele digrafieke), is ook gevind.
Ons gaan verder voort deur ook bereikbare nodusse, bronne en putte in
hierdie bome at te tel. Onder andere verkry ons ’n formule vir die aantal geëtiketteerde
bome met n nodusse waarin presies k nodusse vanaf ’n gegewe
nodus v bereikbaar is asook die gemiddelde aantal nodusse wat bereikbaar
is vanaf ’n gegewe nodus.
Ons enumereer in hierdie tesis verder sekere families van versamelingsverdelings
en soortgelyke boom-vormige strukture. Ons gee ’n bewys vir ’n
formule wat die aantal van samehangende siklus-vrye families van k versamelingsverdelings
op {1, . . . , n} wat ’n sekere koherensie-vereiste bevredig,
en ons beskryf ’n bijeksie tussen hierdie familie en die versameling van
geëtiketteerde vrye k-êre kaktusse met ’n gegewe nodus-graad-verdeling.
Ons toon ook dat hierdie formule ook gekleurde Husimi-grafieke tel waar
blokke van dieselfde kleur nie insident met mekaar mag wees nie. Ons tel
verder ook gekleurde georiënteerde kaktusse en gekleurde kaktusse.
Nie-kruisende bome en soortgelyke boom-vormige strukture word in
hierdie tesis ook beskou. On bepaal spesifiek formules vir lokaal georiënteerde
nie-kruisende bome wat ’n gegewe aantal bronne en putte het asook
nie-kruisende bome met gegewe ingangs- en uitgangsgraadrye. Ons
gaan voort deur die gemiddelde aantal bereikbare nodusse in hierdie bome
te bepaal. Ons veralgemeen dan die konsep van nie-kruisende bome en
vind formules vir die aantal nie-kruisende Husimi-grafieke, kaktusse en
georiënteerde kaktusse. Laastens vind ons ’n formule vir die aantaal tweegekleurde
nie-kruisende Husimi-grafieke en die aantal nie-kruisende samehangende
siklus-vrye pare van versamelingsverdelings.
3
Creus, López Carles. "Tree automata with constraints and tree homomorphisms." Doctoral thesis, Universitat Politècnica de Catalunya, 2016. http://hdl.handle.net/10803/394077.
Full textAbstract:
Automata are a widely used formalism in computer science as a concise representation for sets. They are interesting from a theoretical and practical point of view. This work is focused on automata that are executed on tree-like structures, and thus, define sets of trees. Moreover, we tackle automata that are enhanced with the possibility to check (dis)equality constraints, i.e., where the automata are able to test whether specific subtrees of the input tree are equal or different. Two distinct mechanisms are considered for defining which subtrees have to be compared in the evaluation of the constraints. First, in local constraints, a transition of the automaton compares subtrees pending at positions relative to the position of the input tree where the transition takes place. Second, in global constraints, the subtrees tested are selected depending on the state to which they are evaluated by the automaton during a computation.
In the setting of local constraints, we introduce tree automata with height constraints between brothers. These constraints are predicates on sibling subtrees that, instead of evaluating whether the subtrees are equal or different, compare their respective heights. Such constraints allow to express natural tree sets like complete or balanced (like AVL) trees. We prove decidability of emptiness and finiteness for these automata, and also for their
combination with the tree automata with (dis)equality constraints between brothers of Bogaert and Tison (1992). We also define a new class of tree automata with constraints that allows arbitrary local disequality constraints and a particular kind of local equality constraints. We prove decidability of emptiness and finiteness for this class in exponential time. As a consequence, we obtain several EXPTIME-completeness results for problems on images of
regular tree sets under tree homomorphisms, like set inclusion, finiteness of set difference, and regularity (also called HOM problem).
In the setting of global constraints, we study the class of tree automata with global reflexive disequality constraints. Such kind of constraints is incomparable with the original notion of global disequality constraints of Filiot et al. (2007): the latter restricts disequality tests to only compare subtrees evaluated to distinct states, whereas in our model it is possible to test that all subtrees evaluated to the same given state are pairwise different. Our tests correspond to monadic key constraints, and thus, can be used to characterize unique identifiers, a typical integrity constraint of XML schemas. We study the emptiness and finiteness problems for these automata, and obtain decision algorithms that take triple exponential time.<br>Los autómatas son un formalismo ampliamente usado en ciencias de la computación como una representación concisa para conjuntos, siendo interesantes tanto a nivel teórico como práctico. Este trabajo se centra en autómatas que se ejecutan en estructuras arbóreas, y por tanto, definen conjuntos de árboles. En particular, tratamos autómatas que han sido extendidos con la posibilidad de comprobar restricciones de (des)igualdad, es decir, autómatas que son capaces de comprobar si ciertos subárboles del árbol de entrada son iguales o diferentes. Se consideran dos mecanismos distintos para definir qué subárboles deben ser comparados en la evaluación de las restricciones. Primero, en las restricciones locales, una transición del autómata compara subárboles que penden en posiciones relativas a la posición del árbol de entrada en que se aplica la transición. Segundo, en restricciones globales, los subárboles comparados se seleccionan dependiendo del estado al que son evaluados por el autómata durante el cómputo. En el marco de restricciones locales, introducimos los autómatas de árboles con restricciones de altura entre hermanos. Estas restricciones son predicados entre subárboles hermanos que, en lugar de evaluar si los subárboles son iguales o diferentes, comparan sus respectivas alturas. Este tipo de restricciones permiten expresar conjuntos naturales de árboles, tales como árboles completos o equilibrados (como AVL). Demostramos la decidibilidad de la vacuidad y finitud para este tipo de autómata, y también para su combinación con los autómata con restricciones de (des)igualdad entre hermanos de Bogaert y Tison (1992). También definimos una nueva clase de autómatas con restricciones que permite restricciones locales de desigualdad arbitrarias y un tipo particular de restricciones locales de igualdad. Demostramos la decidibilidad de la vacuidad y finitud para esta clase, con un algoritmo de tiempo exponencial. Como consecuencia, obtenemos varios resultados de EXPTIME-completitud para problemas en imágenes de conjuntos regulares de árboles a través de homomorfismos de árboles, tales como inclusión de conjuntos, finitud de diferencia de conjuntos, y regularidad (también conocido como el problema HOM). En el marco de restricciones globales, estudiamos la clase de autómatas de árboles con restricciones globales de desigualdad reflexiva. Este tipo de restricciones es incomparable con la noción original de restricciones globales de desigualdad de Filiot et al. (2007): éstas últimas restringen las comprobaciones de desigualdad a subárboles que se evalúen a estados distintos, mientras que en nuestro modelo es posible comprobar que todos los subárboles que se evalúen a un mismo estado dado son dos a dos distintos. Nuestras restricciones corresponden a restricciones de clave, y por tanto, pueden ser usadas para caracterizar identificadores únicos, una restricción de integridad típica de los XML Schemas. Estudiamos los problemas de vacuidad y finitud para estos autómatas, y obtenemos algoritmos de decisión con coste temporal triplemente exponencial.
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Mahoney, James Raymond. "Tree Graphs and Orthogonal Spanning Tree Decompositions." PDXScholar, 2016. http://pdxscholar.library.pdx.edu/open_access_etds/2944.
Full textAbstract:
Given a graph G, we construct T(G), called the tree graph of G. The vertices of T(G) are the spanning trees of G, with edges between vertices when their respective spanning trees differ only by a single edge. In this paper we detail many new results concerning tree graphs, involving topics such as clique decomposition, planarity, and automorphism groups. We also investigate and present a number of new results on orthogonal tree decompositions of complete graphs.
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McCarthy, Meghan E. "THE LEMON TREE: MY TREE OF LIFE." CSUSB ScholarWorks, 2014. https://scholarworks.lib.csusb.edu/etd/49.
Full textAbstract:
The Lemon Tree is a collection of poems that arose from my attempt to capture memories of influential experiences in growing up. The poems are written in prose blocks and move in and out of childlike and adult sensibilities, creating the disillusion of time and memory. The poems themselves are comments on the unreliability and limited scope of memory and compare remembrance to dreams. This suggests that time moves more fluidly than the waking world accepts. Through looking back, through prisms, the speaker remembers experiences that impacted her development as we follow her on a journey to coming-of-age. The Lemon Tree grapples with becoming and expressing her female fertility and growth as a woman. The speaker constantly searches for love in places of religion, marriage, romantic relationships and friendships. At times, the poems decide what love is by what it isn’t. The act of creating itself was the aim of the manuscript more than the finished project. Some remembrances are intentionally left unclear and messy like wild weeds. The poems are confessional and bear resemblances to a memoir in a lyrical fashion. The Lemon Tree focuses on the processes of life: both the barren and the abundance of fruit, light and dark, winter and summer. The speaker tries to resolve the binaries of trauma and of love and in the process, finds her identity as seen through the symbol of The Lemon Tree, which ultimately becomes her personal tree of life.
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Abu-Ata, Muad Mustafa. "Tree-Like Structure in Graphs and Embedability to Trees." Kent State University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=kent1397345185.
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Lieberman, Michael (Michael R. ). "Combining phrase-based and tree-to-tree translation." Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/45635.
Full textAbstract:
Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2008.<br>This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.<br>Includes bibliographical references (p. 39-40).<br>We present a novel approach to multi-engine machine translation, using a feature-based classification algorithm. Instead of just using language models, translation models, or internal confidence scores, we sought out other features that could be used to determine which of two translations to select. We combined the outputs from a phrase-based system, Moses [Koehn et al., 2007] and a tree-to-tree system [Cowan et al., 2006]. Our main result is a 0.3 to 0.4 improvement in BLEU score over the best single system used, while also improving fluency and adequacy judgments. In addition, we used the same setup to directly predict which sentences would be judged by humans to be more fluent and more adequate. In those domains, we predicted the better sentence 6% to 7% more often than a baseline of always choosing the single best system.<br>by Michael Lieberman.<br>M.Eng.
8
Götze, Doreen. "Weighted Unranked Tree Automata over Tree Valuation Monoids." Doctoral thesis, Universitätsbibliothek Leipzig, 2017. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-221154.
Full textAbstract:
Quantitative aspects of systems, like the maximal consumption of resources, can be modeled by weighted automata. The usual approach is to weight transitions with elements of a semiring and to define the behavior of the weighted automaton by mul- tiplying the transition weights along a run. In this thesis, we define and investigate a new class of weighted automata over unranked trees which are defined over valuation monoids. By turning to valuation monoids we use a more general cost model: the weight of a run is now determined by a global valuation function. Besides the binary cost functions implementable via semirings, valuation functions enable us to cope with average and discounting. We first investigate the supports of weighted unranked tree automata over valuation monoids, i.e., the languages of all words which are evalu- ated to a non-zero value. We will furthermore consider the support of several other weighted automata models over different structures, like words and ranked trees. Next we prove a Nivat-like theorem for the new weighted unranked tree automata. More- over, we give a logical characterization for them. We show that weighted unranked tree automata are expressively equivalent to a weighted MSO logic for unranked trees. This solves an open problem posed by Droste and Vogler. Finally, we present a Kleene- type result for weighted ranked tree automata over valuation monoids.
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Cha, Kyoung-Choul. "Dream tree /." Online version of thesis, 1995. http://hdl.handle.net/1850/12139.
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Collier, Samantha Noelle. "Silo tree." Thesis, University of Iowa, 2015. https://ir.uiowa.edu/etd/1573.
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Wu, Li. "Distributed true string B-tree peer-to-peer overlay networks." Thesis, University of Ottawa (Canada), 2006. http://hdl.handle.net/10393/27197.
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A fundamental problem that confronts P2P Internet applications is to efficiently locate the physical (IP) node that stores a particular data item. To tackle this application-level routing problem, this thesis proposes a new P2P overlay network, called Distributed True String B-tree (DTSBT) P2P overlay network. Unlike popular Distributed Hash Table (DHT)-based P2P overlay networks which use DHT as their core data structure, the DTSBT P2P overlay network employs a new data structure, DTSBT as its core data structure. A DTSBT is a hybrid distributed data structure, in which all peers' routing tables make up a virtual B-tree and a Patricia Trie is plugged into each peer's routing table. The performance evaluation showed that the DTSBT P2P overlay network is more scalable, decentralized, resilient to failures, and self-organized compared to its competitors.
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Choi, Myung Jin Ph D. Massachusetts Institute of Technology. "Trees and beyond : exploiting and improving tree-structured graphical models." Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/62888.
Full textAbstract:
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2011.<br>This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.<br>Cataloged from student submitted PDF version of thesis.<br>Includes bibliographical references (p. 169-179).<br>Probabilistic models commonly assume that variables are independent of each other conditioned on a subset of other variables. Graphical models provide a powerful framework for encoding such conditional independence structure of a large collection of random variables. A special class of graphical models with significant theoretical and practical importance is the class of tree-structured graphical models. Tree models have several advantages: they can be easily learned given data, their structures are often intuitive, and inference in tree models is highly efficient. However, tree models make strong conditional independence assumptions, which limit their modeling power substantially. This thesis exploits the advantages of tree-structured graphical models and considers modifications to overcome their limitations. To improve the modeling accuracy of tree models, we consider latent trees in which variables at some nodes represent the original (observed) variables of interest while others represent the latent variables added during the learning procedure. The appeal of such models is clear: the additional latent variables significantly increase the modeling power, and inference on trees is scalable with or without latent variables. We propose two computationally efficient and statistically consistent algorithms for learning latent trees, and compare the proposed algorithms to other methods by performing extensive numerical experiments on various latent tree models. We exploit the advantages of tree models in the application of modeling contextual information of an image. Object co-occurrences and spatial relationships can be important cues in recognizing and localizing object instances. We develop tree-based context models and demonstrate that its simplicity enables us to integrate many sources of contextual information efficiently. In addition to object recognition, we are interested in using context models to detect objects that are out of their normal context. This task requires precise and careful modeling of object relationships, so we use a latent tree for object co-occurrences. Many of the latent variables can be interpreted as scene categories, capturing higher-order dependencies among object categories. Tree-structured graphical models have been widely used in multi-resolution (MR) modeling. In the last part of the thesis, we move beyond trees, and propose a new modeling framework that allows additional dependency structure at each scale of an MR tree model. We mainly focus on MR models with jointly Gaussian variables, and assume that variables at each scale have sparse covariance structure (as opposed to fully-uncorrelated structure in MR trees) conditioned on variables at other scales. We develop efficient inference algorithms that are partly based on inference on the embedded MR tree and partly based on local filtering at each scale. In addition, we present methods for learning such models given data at the finest scale by formulating a convex optimization problem.<br>by Myung Jin Choi.<br>Ph.D.
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King, Stuart. "Optimizations and applications of Trie-Tree based frequent pattern mining." Diss., Connect to online resource - MSU authorized users, 2006.
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Thesis (M. S.)--Michigan State University. Dept. of Computer Science and Engineering, 2006.<br>Title from PDF t.p. (viewed on June 19, 2009) Includes bibliographical references (p. 79-80). Also issued in print.
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Zhu, Sha (Joe). "Stochastic tree models and probabilistic modelling of gene trees of given species networks." Thesis, University of Canterbury. Department of Mathematics and Statistics, 2013. http://hdl.handle.net/10092/7944.
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In the pre-genomic era, the relationships among species and their evolutionary histories were often determined by examining the fossil records. In the genomic era, these relationships are identified by analysing the genetic data, which also enables us to take a close-up view of the differences between the individual samples. Nevertheless, these relationships are often described by a tree-like structure or a network. In this thesis, we investigate some of the models that are used to describe these relationships.
This thesis can be divided into two main parts. The first part focuses on investigating the theoretical properties of several neutral tree models that are often considered in phylogenetics and population genetics studies, such as the Yule–Harding model, the proportional to distinguishable arrangements and the Kingman coalescent models.
In comparison to the first part, the other half of the thesis is more computationally
oriented: we focus on developing and implementing methods of calculating gene tree probabilities of given species networks, and simulating genealogies within species networks.
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SANTOS, ALEXANDRE JOSE DOS. "TREE-STRUCTURE SMOOTH TRANSITION VECTOR AUTOREGRESSIVE MODELS – STVAR-TREE." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2009. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=15888@1.
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COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR<br>Esta dissertação tem como objetivo principal introduzir uma formulação de
modelo não-linear multivariado, a qual combina o modelo STVAR (Smooth
Transition Vector Autoregressive) com a metodologia CART (Classification and
Regression Tree) a fim de utilizá-lo para geração de cenários e de previsões. O
modelo resultante é um Modelo Vetorial Auto-Regressivo com Transição Suave
Estruturado por Árvores, denominado STVAR-Tree e tem como base o conceito
de múltiplos regimes, definidos por árvore binária. A especificação do modelo é
feita através do teste LM. Desta forma, o crescimento da árvore é condicionado à
existência de não-linearidade nas séries, que aponta a divisão do nó e a variável de
transição correspondente. Em cada divisão, são estimados os parâmetros lineares,
por Mínimos Quadrados Multivariados, e os parâmetros não-lineares, por
Mínimos Quadrados Não-Lineares. Como forma de avaliação do modelo STVARTree,
foram realizados diversos experimentos de Monte Carlo com o objetivo de
constatar a funcionalidade tanto do teste LM quanto da estimação do modelo.
Bons resultados foram obtidos para amostras médias e grandes. Além dos
experimentos, o modelo STVAR-Tree foi aplicado às séries brasileiras de Vazão
de Rios e Preço Spot de energia elétrica. No primeiro estudo, o modelo foi
comparado estatisticamente com o Periodic Autoregressive (PAR) e apresentou
um desempenho muito superior ao concorrente. No segundo caso, a comparação
foi com a modelagem Neuro-Fuzzy e ganhou em uma das quatro séries. Somando
os resultados dos experimentos e das duas aplicações conclui-se que o modelo
STVAR-Tree pode ser utilizado na solução de problemas reais, apresentando bom
desempenho.<br>The main goal of the dissertation is to introduce a nonlinear multivariate
model, which combines the model STVAR (Smooth Transition Vector
Autoregressive) with the CART (Classification and Regression Tree) method and
use it for generating scenarios and forecasting. The resulting model is a Tree-
Structured Vector Autoregressive model with Smooth Transition, called STVARTree,
which is based on the concept of multiple regimes, defined by binary tree.
The model specification is based on Lagrange Multiplier tests. Thus, the growth
of the tree is conditioned on the existence of nonlinearity in the time series, which
indicates the node to be split and the corresponding transition variable. In each
division, linear parameters are estimated by Multivariate Least Squares, and
nonlinear parameters by Non-Linear Least Squares. As a way of checking the
STVAR-Tree model, several Monte Carlo experiments were performed in order to
see the functionality of both the LM test and the model estimation. Best results
were obtained with medium and large samples. Besides, the STVAR-Tree model
was applied to Brazilian time series of Rivers Flow and electricity spot price. In
the first study, the model was statistically compared to the Periodic
Autoregressive (PAR) model and had a much higher performance than the
competitor. In the second case, the model comparison was with Neural-Fuzzy
Modeling and the STVAR-Tree model won in one of the four series. Adding both
the experiments and the two applications results we conclude that the STVARTree
model may be applied to solve real problems, having good results.
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Cowan, Brooke A. (Brooke Alissa) 1972. "A tree-to-tree model for statistical machine translation." Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/44689.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2008.<br>Includes bibliographical references (p. 227-234).<br>In this thesis, we take a statistical tree-to-tree approach to solving the problem of machine translation (MT). In a statistical tree-to-tree approach, first the source-language input is parsed into a syntactic tree structure; then the source-language tree is mapped to a target-language tree. This kind of approach has several advantages. For one, parsing the input generates valuable information about its meaning. In addition, the mapping from a source-language tree to a target-language tree offers a mechanism for preserving the meaning of the input. Finally, producing a target-language tree helps to ensure the grammaticality of the output. A main focus of this thesis is to develop a statistical tree-to-tree mapping algorithm. Our solution involves a novel representation called an aligned extended projection, or AEP. The AEP, inspired by ideas in linguistic theory related to tree-adjoining grammars, is a parse-tree like structure that models clause-level phenomena such as verbal argument structure and lexical word-order. The AEP also contains alignment information that links the source-language input to the target-language output. Instead of learning a mapping from a source-language tree to a target-language tree, the AEP-based approach learns a mapping from a source-language tree to a target-language AEP. The AEP is a complex structure, and learning a mapping from parse trees to AEPs presents a challenging machine learning problem. In this thesis, we use a linear structured prediction model to solve this learning problem. A human evaluation of the AEP-based translation approach in a German-to-English task shows significant improvements in the grammaticality of translations. This thesis also presents a statistical parser for Spanish that could be used as part of a Spanish/English translation system.<br>by Brooke Alissa Cowan.<br>Ph.D.
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Teichmann, Markus. "Expressing Context-Free Tree Languages by Regular Tree Grammars." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2017. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-224756.
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In this thesis, three methods are investigated to express context-free tree languages by regular tree grammars. The first method is a characterization. We show restrictions to context-free tree grammars such that, for each restricted context-free tree grammar, a regular tree grammar can be constructed that induces the same tree language. The other two methods are approximations. An arbitrary context-free tree language can be approximated by a regular tree grammar with a restricted pushdown storage. Furthermore, we approximate weighted context-free tree languages, induced by weighted linear nondeleting context-free tree grammars, by showing how to approximate optimal weights for weighted regular tree grammars.
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Yao, Chu. "Quad general tree drawing algorithm and general trees characterization : towards an environment for the experimental study on general tree drawing algorithms /." Full text available online, 2008. http://www.lib.rowan.edu/find/theses.
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Goldman, Daniel A. "Multidimensional range searching using G-tree and B*-tree indexing." Diss., Online access via UMI:, 2005.
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Cambronero, Christoffer. "The Brownian tree." Thesis, Uppsala universitet, Matematisk statistik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-208571.
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Fitzgerald, Caitlin Anne. "The Thorn Tree." Thesis, Boston College, 2007. http://hdl.handle.net/2345/376.
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Thesis advisor: Thomas Kaplan-Maxfield<br>We remember childhood injustices for the rest of our lives. They are thorn-like memories, piercing and immediate, affecting us long after we have matured and moved on with our lives. The wounds of childhood have been written about by some of literature's greatest writers, including most notably James Joyce, in his masterpiece A Portrait of the Artist as a Young Man. In this creative work I try to investigate, through the voices of children, the role of wounds in the growing character of a child. Wounds both literal and metaphorical dominate the narrative, which is told from a variety of perspectives as one group of friends from one neighborhood advance through elementary school. My goal in this work is to portray the painfully observant nature of children — to show how much they absorb in the early years of their lives, the scope of which adults might not realize. I also try to capture the humor and tragedy of children's voices, and to create a whole world as seen through the eyes of children<br>Thesis (BA) — Boston College, 2007<br>Submitted to: Boston College. College of Arts and Sciences<br>Discipline: English<br>Discipline: College Honors Program
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George, Zachary J. Sir. "Beneath Cuoi's Tree." ScholarWorks@UNO, 2012. http://scholarworks.uno.edu/td/1589.
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Phillips, Esther P. "Ghost Tree Social." FIU Digital Commons, 2013. http://digitalcommons.fiu.edu/etd/829.
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GHOST TREE SOCIAL tells a coming out story of sorts. In terms of style, many of the poems are short, imagistic lyrics, though some are extended catalogues. Specific natural images—lakes, rivers, and snow—are often contrasted with cultural markers. The imagistic poems are thinking through the work of Sylvia Plath. The catalogue poems shift between diaristic, narrative, and critical modes, responding to the poetry of Elizabeth Bishop and the essays of Edouard Glissant.
Voice-driven fragments disrupt the more traditional lyric poems. The fragments fall between formal lyrics like confetti from a gay club’s rafters; or the fragments hold the lyric poems in bondage. The lyric poem then re-signifies as form through resonances with the other discursive and poetic form of the fragment. Following critical writers such as Adrienne Rich and Audre Lorde, the re-signification of lyric form reflects the need for new signs for self and community organized queerly as opposed to more typical binary categories—man or woman, living or dead, rich or poor, white or black—where the first term is privileged and the second term often denigrated.
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Rudd, Ralph. "Optimal tree methods." Master's thesis, University of Cape Town, 2014. http://hdl.handle.net/11427/8567.
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Includes bibliographical references.<br>Although traditional tree methods are the simplest numerical methods for option pricing, much work remains to be done regarding their optimal parameterization and construction. This work examines the parameterization of traditional tree methods as well as the techniques commonly used to accelerate their convergence. The performance of selected, accelerated binomial and trinomial trees is then compared to an advanced tree method, Figlewski and Gao's Adaptive Mesh Model, when pricing an American put and a Down-And-Out barrier option.
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Pogson, Aimee L. "Tree Frog Madness." Bowling Green State University / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1245380440.
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Rossin, Samuel. "Steiner Tree Games." Oberlin College Honors Theses / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=oberlin1464700445.
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Mahonski, Christopher. "A TLAPALIZQUIXOCHITL TREE." VCU Scholars Compass, 2009. http://scholarscompass.vcu.edu/etd/1838.
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Lee, William W. L. (William Wai Lam) Carleton University Dissertation Computer Science. "Tree editing algorithms." Ottawa, 1992.
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Carlsson, David. "Tree trunk image classifier : Image classification of trees using Collaboratory, Keras and TensorFlow." Thesis, Linnéuniversitetet, Institutionen för datavetenskap och medieteknik (DM), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-98698.
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In the forestry industry tree trunks are currently classified manually. The object of this thesis is to answer whether it is possible to automate this using modern computer hardware and image-classification of tree-trunks using machine learning algorithms. The report concludes, based on results from controlled experiments that it is possible to achieve an accuracy above 90% across the genuses Birch, Pine and Spruce with a classification-time per tree shorter than 500 milli seconds. The report further compares these results against previous research and concludes that better results are probable.
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MacKinnon, Richard Kyle. "Seeing the forest for the trees: tree-based uncertain frequent pattern mining." Springer International Publishing, 2014. http://hdl.handle.net/1993/31059.
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Many frequent pattern mining algorithms operate on precise data, where each data point is an exact accounting of a phenomena (e.g., I have exactly two sisters). Alas, reasoning this way is a simplification for many real world observations. Measurements, predictions, environmental factors, human error, &ct. all introduce a degree of uncertainty into the mix. Tree-based frequent pattern mining algorithms such as FP-growth are particularly efficient due to their compact in-memory representations of the input database, but their uncertain extensions can require many more tree nodes. I propose new algorithms with tightened upper bounds to expected support, Tube-S and Tube-P, which mine frequent patterns from uncertain data. Extensive experimentation and analysis on datasets with different probability distributions are undertaken that show the tightness of my bounds in different situations.<br>February 2016
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Tong, Mei-ka Julie. "Tree planting and air quality in Hong Kong urban areas /." View the Table of Contents & Abstract, 2005. http://sunzi.lib.hku.hk/hkuto/record/.
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Larson, Heidi Elaine. ""Alchemy of Desire/Dead Man's Blues": To Tree Or Not To Tree." OpenSIUC, 2015. https://opensiuc.lib.siu.edu/theses/1768.
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The subjects of grief and of the afterlife are ones that have been discussed and analyzed for centuries, with no conclusive answers as to where we go or how we should go on. In “Alchemy of Desire/ Dead Man’s Blues”, Caridad Svich continues this discussion through a narrative, centered around a group of women dealing with the aftermath of a loss. She uses the term alchemy as an allegory for one’s ability to transcend and transform, and in turn, come to know the meaning of life…and death. This paper serves as a documentation of the SIUC Theater Department’s process and results in bringing this conversation to the stage, and this story to life.
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Biondi, Franco. "Development of a Tree-Ring Network for the Italian Peninsula." Tree-Ring Society, 1992. http://hdl.handle.net/10150/262358.
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This article describes the analysis of tree-ring collections from standing trees of sixteen species at twenty sites distributed throughout the Italian Peninsula. Visual and numerical crossdating among ring widths allowed the computation of standard and residual tree-ring chronologies. Relationships among chronologies were identified by Spearman's coefficient of rank correlation, using Bonferroni's inequality to adjust significance level. The oldest living tree sampled to date is a 963-year old palebark pine (Pinus leucodermis Ant.) at Parco del Pollino. Individuals more than two centuries old were identified at eleven sites for eight species. The tree-ring network so far consists of twenty-two chronologies for nine species at nineteen sites. Seven conifer species account for ten chronologies and two angiosperm species account for the remaining twelve chronologies. The most represented species is Fagus sylvatica L., with eleven chronologies distributed over the entire peninsula and highly correlated with one another. The order of autoregressive models fitted to the data never exceeded two. In particular, the order of autoregressive models fitted to Fagus sylvatica chronologies decreased with decreasing age of sampled trees. Based on the significant coefficients of rank correlation, residual chronologies of Fagus sylvatica could be separated into northern, central, and southern groups. This points to the existence of broad regions distributed along a latitudinal gradient, corresponding to large-scale climatic regimes over the Italian Peninsula.
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Grissino-Mayer, Henri D. "An Updated List of Species Used in Tree-Ring Research." Tree-Ring Society, 1993. http://hdl.handle.net/10150/262378.
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During the past 100 years, researchers have investigated the potential of hundreds of tree and shrub species for use in applications of tree-ring research. Although several lists of species known to crossdate have been published, investigated species that do not crossdate are rarely included despite the usefulness of this information for future research. This paper provides a list of the Latin and common names of 573 species that have been investigated in tree-ring research, information on species known to crossdate, and information on species with measurement and/or chronology data in the International Tree-Ring Data Bank. In addition, a measure of the suitability of a species for future tree-ring applications, the Crossdating Index (CDI), is developed and proposed for standard usage.
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Bhattacharyya, Amalava, Valmore C. Jr LaMarche, and Malcolm K. Hughes. "Tree-Ring Chronologies from Nepal." Tree-Ring Society, 1992. http://hdl.handle.net/10150/262376.
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Ten ring-width based chronologies from Nepal are described and the prospects for further dendroclimatic work there reviewed briefly. The initial results are encouraging, and more intensive subregional sampling is called for. All the cores examined showed distinct annual rings, and there was little evidence of double or missing rings, except juniper at some sites and in some Pinus roxburghii trees. Difficulty was encountered in dating Pinus wallichiana and Cupressus dumosa. Individual site chronologies of Cedros deodora, P. roxburghii and P. wallichiana were particularly promising, and of high elevation Abies spectabilis moderately so. Densitometric data are likely to be more useful for this species. The paucity of meteorological data in Nepal represents an obstacle to further dendroclimatic work there.
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Daciuk, Jan. "Perfect hashing tree automata." Universität Potsdam, 2008. http://opus.kobv.de/ubp/volltexte/2008/2716/.
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We present an algorithm that computes a function that assigns consecutive integers to trees recognized by a deterministic, acyclic, finite-state, bottom-up tree automaton. Such function is called minimal perfect hashing. It can be used to identify trees recognized by the automaton. Its value may be seen as an index in some other data structures. We also present an algorithm for inverted hashing.
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Davies, Nicholas Tuatahi. "Reverse Engineering the Tree." Thesis, University of Canterbury. Forestry, 2014. http://hdl.handle.net/10092/9600.
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The aim of this thesis was to investigate the typical radial pattern of density and microfibril angle within Pinus radiata with respect to structural stability. In order to investigate changes in mechanical stability with different radial patterns, first experimental work was carried out in order to obtain elastic constants, Poisson ratios and limits of proportionality for green corewood and outerwood, these values, a discussion on their accuracy and the implications of the values are included along with a comparison to previous literature. These constants were used to parametrise a finite element model of a tree stem with different radial patterns, including patterns not observed in nature, wind loadings were applied to the stem and failure evaluated. It was found that patterns consisting of high density stiff wood and/or low density high flexibility wood could withstand the greatest wind speeds for a given stem and canopy, while high density flexible and low density stiff profiles generally performed poorly. The analysis was considered at ages 5, 10 and 15 years, each providing similar results. Why these profiles perform best, what errors need to be considered, and other evolutionary pressures which could narrow this list of profiles were discussed. The need for further research, and the directions for this research are suggested.
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Östlund, Klara. "The Tree House Project." Thesis, KTH, Arkitektur, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-168925.
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To be truly rooted in my final degree project, I decided to go back to something that fascinated me as a child; To live among the trees. I remember trees standing out as individuals, as landmarks, and as architecture. Cultures all around the world displays importance in their relationship to trees, be it a source for shelter, food, symbolic references or playing as a child. This project explores the actual building process, when constructing something in a living tree. It turns into both a physical and mental challange. This project is divided into two main modes; (1) a research activity, and (2) a building action. The method is almost an intuitive one, being in the tree, at the construction site, as I both come up with design concepts, metaphores and physical solutions for the project. The conclusions are both sketches and real solutions as much as the actual final tree house experience. The site is situated about 10 km south of Uppsala, Sweden.<br>För att ha en tydlig grund i mitt sista projekt i utbildningen, valde jag att gå tillbaka till något som fascinerade mig som barn, att bo bland trädtopparna. Jag minns träd som individer, som landmärken och som arkitektur i sig själva. I alla kulturer runt planeten finns tydliga relationer till träden, om det är en källa för mat och husrum, symboliken i religioner, och lekfullheten hos barn. Det här projektet utforskar själva byggnadsprocessen, genom att bygga i ett levande träd. Det blir både en fysisk och en mental utmaning. Projektets process har fortgått i två huvudsakliga grenar, (1) en forskingsaktivitet, och (2) ett konstruktionsexperiment. Metoden har varit nästan intuitiv, varandet i naturen och i trädet har fått styra både konstruktionen och designidéer. Slutprodukten åär både skisser, och riktiga fysiska lösningar, samt erfarenheten av att vara i själva trädhuset. Platsen för bygganden ligger ungefär 10 km söder om Uppsal, Sverige.
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Curtin, Ryan Ross. "Improving dual-tree algorithms." Diss., Georgia Institute of Technology, 2015. http://hdl.handle.net/1853/54354.
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This large body of work is entirely centered around dual-tree algorithms, a
class of algorithm based on spatial indexing structures that often provide large amounts of acceleration for various problems. This work focuses on understanding dual-tree algorithms using a new, tree-independent abstraction, and using this abstraction to develop new algorithms. Stated more clearly, the thesis of this entire work is that we may improve and expand the class of dual-tree algorithms by focusing on and providing improvements for each of the three independent components of a dual-tree algorithm: the type of space tree, the type of pruning dual-tree traversal, and the problem-specific BaseCase() and Score() functions. This is demonstrated by expressing many existing dual-tree algorithms in the tree-independent framework, and focusing on improving each of these three pieces. The result is a formidable set of generic components that can be used to assemble dual-tree algorithms, including faster traversals, improved tree theory, and new algorithms to solve the problems of max-kernel search and k-means clustering.
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Lucas, Maree Eleanor. "Allocation in tree seedlings." Thesis, University of Edinburgh, 1998. http://hdl.handle.net/1842/12482.
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The hypothesis that allocation between the main tree components is controlled by the relative uptake rates of carbon dioxide and nutrient was tested by growing one-year-old sycamore seedlings (<I>Acer pseudoplatanus</I> L.) at elevated and ambient CO<SUB>2</SUB> concentrations and at two nutrient addition rates which were modelled in accordance with a predicted optimal growth function. Elevated CO<SUB>2</SUB> concentration significantly increased the leaf dry mass but did not significantly change the dry mass of any other component. In contrast nutrient addition rate had large effects on all biomass components with the exception of the root. Allocation was strongly affected by nutrient addition rate although CO<SUB>2</SUB> treatment only affected the allocation to the stem. Nutrient concentrations were reduced by growth at elevated CO<SUB>2</SUB> concentrations. Leaf starch concentrations were larger at elevated CO<SUB>2</SUB> concentrations. There were no differences in soluble leaf carbohydrate concentrations between treatments. There was evidence of downregulation of photosynthesis at the low nutrient addition rate but not at elevated CO<SUB>2</SUB> concentrations. In conclusion, the growth concentration of CO<SUB>2</SUB> and nutrient and water availabilities are important in the control of allocation. Increases in atmospheric CO<SUB>2</SUB> concentrations are likely to be accompanied by shifts in allocation towards the root and stem although the magnitude of these changes will be determined by the nutrient availability of soils. The effects of perturbations in these variables are also determined by differences in growth and allocation between clones of the same species, between species and by the development of allocation patterns which are dependent on phenology. The functional balance is useful in predicting changes in allocation, although it does not fully explain the observed patterns.
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Gibbons, Jeremy. "Algebras for tree algorithms." Thesis, University of Oxford, 1991. http://ora.ox.ac.uk/objects/uuid:50ed112d-411d-486f-8631-6064138f4bf7.
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This thesis presents an investigation into the properties of various algebras of trees. In particular, we study the influence that the structure of a tree algebra has on the solution of algorithmic problems about trees in that algebra. The investigation is conducted within the framework provided by the Bird-Meertens formalism, a calculus for the construction of programs by equational reasoning from their specifications. We present three different tree algebras: two kinds of binary tree and a kind of general tree. One of the binary tree algebras, called "hip trees", is new. Instead of being built with a single ternary operator, hip trees are built with two binary operators which respectively add left and right children to trees which do not already have them; these operators enjoy a kind of associativity property. Each of these algebras brings with it with a class of "structure-respecting" functions called catamorphisms; the definition of a catamorphism and a number of its properties come for free from the definition of the algebra, because the algebra is chosen to be initial in a class of algebras induced by a (cocontinuous) functor. Each algebra also brings with it, but not for free, classes of "structure-preserving" functions called accumulations. An accumulation is a function that preserves the shape of a structured object such as a tree, but replaces each element of that object with some catamorphism applied to some of the other elements. The two classes of accumulation that we study are the "upwards" and "downwards" accumulations, which pass information from the leaves of a tree towards the root and from the root towards the leaves, respectively. Upwards and downwards accumulations turn out to be the key to the solution of many problems about trees. We derive accumulation-based algorithms for a number of problems; these include the parallel prefix algorithm for the prefix sums problem, algorithms for bracket matching and for drawing binary and general trees, and evaluators for decorating parse trees according to an attribute grammar.
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Shuja, Aneela. "Under the Pomegranate Tree." ScholarWorks@UNO, 2013. http://scholarworks.uno.edu/td/1784.
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Mina is a young girl in a rural village called Tobay in Pakistan when her only friend Dhaaga, a family servant around her age, suddenly leaves. After a betrayal by her father’s second, much younger wife, Mina starts her long journey. She becomes a prostitute in Heera Mandi, the famed red light district of Lahore, and unexpectedly finds friends in a nearby transvestite brothel. Mina suddenly ends up with her life in danger when she tries to take revenge on the man who ruined Dhaaga’s life. She gets help from a human rights lawyer and escapes to safety in America with a New Orleans cabbie, who she met during her Heera Mandi days. She is eventually forced to come back to Pakistan and finally returns to her home in Tobay, where she finds that everything has changed as much as she has. The novel is set in 1980s Pakistan, when the country faced increasing religious pressure from its military government, and girls like Mina got caught up in stricter standards of honor. It is a coming-of-age novel that takes the protagonist around the world before she is able to finally face her djinns and demons.
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Hurdle, David A. "The Giving Tree Academy." Scholarship @ Claremont, 2017. http://scholarship.claremont.edu/cmc_theses/1457.
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A proposal for a new preschool based in Pomona, California, targeted towards children from low-income backgrounds. Includes extensive research on preschool nationwide, the state of California, and in Pomona. Within the paper a new preschool curriculum and specific teacher practices are discussed. Intended as a model for a new school. or to be adapted for use in educational policy.
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Barros, Rodrigo Coelho. "Evolutionary model tree induction." Pontifícia Universidade Católica do Rio Grande do Sul, 2009. http://hdl.handle.net/10923/1687.
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Previous issue date: 2009<br>Model trees are a particular case of decision trees employed to solve regression problems, where the variable to be predicted is continuous. They have the advantage of presenting an interpretable output, helping the end-user to get more confidence in the prediction and providing the basis for the end-user to have new insight about the data, confirming or rejecting hypotheses previously formed. Moreover, model trees present an acceptable level of predictive performance in comparison to most techniques used for solving regression problems. Since generating the optimal model tree is a NPComplete problem, traditional model tree induction algorithms make use of a greedy top-down divideand- conquer strategy, which may not converge to the global optimal solution. In this work, we propose the use of the evolutionary algorithms paradigm as an alternate heuristic to generate model trees in order to improve the convergence to global optimal solutions. We test the predictive performance of this new approach using public UCI data sets, and we compare the results with traditional greedy regression/model trees induction algorithms. Results show that our approach presents a good tradeoff between predictive performance and model comprehensibility, which may be crucial in many data mining applications.<br>Árvores-modelo são um caso particular de árvores de decisão aplicadas na solução de problemas de regressão, onde a variável a ser predita é contínua. Possuem a vantagem de apresentar uma saída interpretável, auxiliando o usuário do sistema a ter mais confiança na predição e proporcionando a base para o usuário ter novos insights sobre os dados, confirmando ou rejeitando hipóteses previamente formadas. Além disso, árvores-modelo apresentam um nível aceitável de desempenho preditivo quando comparadas à maioria das técnicas utilizadas na solução de problemas de regressão. Uma vez que gerar a árvore-modelo ótima é um problema NP-Completo, algoritmos tradicionais de indução de árvores-modelo fazem uso da estratégia gulosa, top-down e de divisão e conquista, que pode não convergir à solução ótima-global. Neste trabalho é proposta a utilização do paradigma de algoritmos evolutivos como uma heurística alternativa para geração de árvores-modelo. Esta nova abordagem é testada por meio de bases de dados de regressão públicas da UCI, e os resultados são comparados àqueles gerados por algoritmos gulosos tradicionais de indução de árvores-modelo. Os resultados mostram que esta nova abordagem apresenta uma boa relação custo-benefício entre desempenho preditivo e geração de modelos de fácil interpretação, proporcionando um diferencial muitas vezes crucial em diversas aplicações de mineração de dados.
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Shi, Weiwei. "Tree-Inspired Water Harvesting." Diss., Virginia Tech, 2020. http://hdl.handle.net/10919/97604.
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In this work, we were motivated to develop novel devices for water harvesting inspired by natural trees, and to understand their collection efficiency and working principles. We accomplished that with scale-model and large-scale fog harps, floating leaves, and synthetic trees. Fluids mechanics, physics, and thermodynamics were applied to solve the problems and rationalize the results. Redwood-inspired fog harps were designed with stainless steel vertical wires, using 3D-printing and laser-cutting techniques. Fog harps always harvested more water than any of the meshes, tested both under heavy fog and light fog conditions. The aerodynamic efficiency, deposition efficiency, and sliding efficiency were calculated to compare the fog harvesting performance. These findings provide insight into the new design of fog harvesters with high-efficiency fog harvesting performance, and future development of large fog harps, applied into regions even with light fog conditions, as an economically viable means. synthetic trees were fabricated with a nanoporous ceramic disk and silicone tubes. This tree system was tested in an environmental chamber (6 cm short trees) or a plant growth chamber (3m tall trees), both with controlled ambient humidities. The system pressure was calculated with Darcy's equation, Poiseuille equation and Laplace equation. The stable transpiration can happen to any scalable tree, which pumps water up an array of large tubes. Our synthetic trees, like natural trees, have the ability to lift water across a wide range of water temperatures and ambient humidities. They can be used as the large-scale evaporation-driven hydraulic pump, for example, pumped storage hydropower, filtration, underground water extraction.<br>Doctor of Philosophy<br>The purpose of this work is to investigate and characterize novel techniques for water harvesting that are inspired by natural trees. We are interested in two modes of water harvesting in particular: fog harps and synthetic trees. Fog harps were comprised of only vertical wires, inspired by the parallel structures of redwoods, which can capture and shed off fog droplets efficiently. Fog harps harvested more water than the traditional mesh nets, both under heavy fog and light fog conditions. Redwood-inspired fog harps have the high-efficient fog harvesting performance. They can be set up at coastal deserts to collect water from fog, where there is scarce rainfall but plenty of fog, like Chile, Peru and South Africa. Synthetic trees were designed with nanoporous disk (leaf) and tubes (xylem conduits), inspired by the transpiration process in natural trees. This transpiration-powered pump can lift water against the gravity at large scales, driven by the water evaporating from the nanopores. They can be used as the large-scale evaporation-driven hydraulic pump, for example, pumped storage hydropower, filtration, underground water extraction.
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Case, Bonita. "The avocado pear tree." Master's thesis, University of Cape Town, 1999. http://hdl.handle.net/11427/22438.
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For twenty years Elsie September has refused to visit her uncle, Hannie, a state patient at Valkenberg mental hospital. At her grandmother's insistence, she almost goes to see him one day, but she only gets as far as the building and cannot bring herself to go inside. Instead, she meets Shaun and, as a relationship develops, Elsie begins to tell him the stories of her childhood. But Elsie's relationship with Shaun is troubled and unbalanced. Before Elsie reaches the point in her narrative where she will explain why she refuses to see her uncle, she and Shaun part acrimoniously and he disappears. Elsie has, by now, become so caught up in the telling of her story that not even Shaun's disappearance can stop her from going back to the day her world changed beneath the sheltering arms of the avocado pear tree.
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Nigussie, Yared. "Tree ideals and algorithms /." The Ohio State University, 1999. http://rave.ohiolink.edu/etdc/view?acc_num=osu1488187049542378.
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Fleischman, Kimberly Ann. "Sheep Hill Community Tree." VCU Scholars Compass, 2004. http://scholarscompass.vcu.edu/etd/1357.
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An urban community is a fusion of new and old that is constantly changing. We understand better the plight of a community through raising awareness of its unique history and visual character. Linking individual and community experiences offers an opportunity for dialogue, especially as long-time residents and their new neighbors learn about their different pasts and explore their common future. Community building happens from within, when many individuals sharing common values create positive change.
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Özbakış, Başak Kuştepeli Alp. "Fibonacci Fractal Tree Antennas/." [s.l.]: [s.n.], 2004. http://library.iyte.edu.tr/tezler/master/elektrikveelektronikmuh/T000455.rar.
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Liao, Chun-Chieh, and 廖俊傑. "Constrained Tree Inclusion on Ordered Trees." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/63164030771019230269.
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碩士<br>國立暨南國際大學<br>資訊工程學系<br>97<br>Tree P is included in tree T, denoted as P ⊆ T, if and only P is isomorphic to T' where T' is derived from T through a sequence of node deletions. Tree inclusion problem is to determine if P ⊆ T or not. Constrained tree inclusion problem is a kind of tree inclusion problem with node deleted having degree one or two. It can be solved in polynomial time for both unordered and ordered trees.
This problem first appeared in Gabriel Valiente's paper. His paper gives an algorithm in bottom-up strategy to solve the problem. The algorithm can be used in both ordered and unordered trees. The algorithm for ordered trees takes O(mn) time and additional O(mn) space.
In this paper, only ordered trees are discussed. We provide a new algorithm in top-down strategy which is more intuitive. We recursively search that whether there exists an embedding from P to T. It takes O(mn*leaves(T)) time but only additional O(n*leaves(T)) space.