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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

The contested “White Lady”: Perceptions and social meanings of the “White Lady” in Auckland.

Neill, Lindsay John January 2009 (has links)
The White Lady (WL) is a mobile fast food takeaway eatery. The WL has been trading in Auckland City’s central business district for almost fifty years. The WL opens in the early evening and remains open until the early morning hours. At closing, the WL is towed to a storage area where it remains until this process is repeated. This daily pattern has occurred since the WL opened in 1948. Because of its longevity, the WL, and many of its stakeholders have experienced ongoing change as Auckland City has grown, and competition within fast food has increased. Thus, for many stakeholders, the WL is representative of their lives, a mirror of their reality and life experiences. Obviously, these realities and experiences are different for different stakeholders. In this thesis, I examine the contested “White Lady” (WL): the perceptions and the social meanings that its stakeholder groups attribute to it. This thesis illuminates differences and similarities within stakeholder viewpoints and in doing so defines that pie carts like the WL are a valid part of New Zealand’s culinary and social cultures Ultimately, this thesis provides a platform of knowledge from which stakeholders and others can come to understand and know the differing and similar views that other stakeholder groups hold. With this in mind, this research ranges in scope from the examination of city administration to the symbolism associated with the (WL) by some of its stakeholders. Therefore, this research is founded within socio-historic constructs: the history of fast food and, the similarities that this history holds to today’s WL operation. The contextualisation of hospitality within “three domains” (Lashley, 2004, p.13) aids in defining the WL as well as recognising the competitive growth of New Zealand’s fast food industry. This research suggests that fast food growth and subsequent competition have had negative impacts upon many small fast food outlets including the WL. viii The growth of fast food has facilitated a “slow food” (Jones, Shears, Hiller Comfort and Lowell, 2003, p. 298) movement. This movement coupled with the hierarchy of food typologies, adds a Saussurian overlay and sociological discourse to this work. This overlay clarifies for the reader Bourdieu’s (1984) position that all food is reflective of class status. Within postmodernist constructs and the rise of the individual, (and the consequent opportunity to hear ‘voices from the margins’), movement within class and individuality within New Zealand’s wider culture has occurred. Social change therefore, has facilitated some of the issues within WL contestation. In highlighting Bourdieu’s (1984) concept, the “binary opposition” (Levi-Strauss, 1981, as cited in Adamenko, 2007, p.27) inherent within food hierarchies and, as often expressed within the media, is examined. This examination reveals that while the media inform, this information often contributes to the polarisation of opinion that facilitates the formation of contested viewpoints by WL stakeholders. It is against a backdrop of compliance need, the absence of an official street trading policy, the differing views of stakeholders, and the intensification of competition in fast food, coupled with a lacuna in the knowledge base of younger Auckland residents regarding the WL that this research finds its voice.
12

Řízení inverzního kyvadla programovatelným automatem / Control of real cart pole balancer by PLC

Mitiska, Daniel January 2009 (has links)
This thesis deals with design of inversion pendulum, pole rod balancing on mobile vehicle.In the first part is described projection and realisation of mechanical part of the task, the problems encountered during the projection and eventuallly its final solution. Follows verification of the mechanical and electrical part and testing of possibilities of operating by programated machine.
13

Geospatial relationships of tree species damage caused by Hurricane Katrina in south Mississippi

Garrigues, Mark William 06 August 2011 (has links)
This study examined Hurricane Katrina damage in southeast Mississippi to identify stand and site characteristics that may contribute to wind-related damage. Aggregated forest plot-level biometrics were coupled with storm meteorology, topographical features, and soil attributes using GIS techniques to produce damage maps for specific tree species. Regression Tree Analysis was utilized to explore the relationship between damage type and distance variables (distance to coast/storm track). Results indicated that the total damage class had the greatest relationship with distance variables; individual damage classes (shear and blowdown) displayed a better relationship with stand-level variables (Quadratic Mean Diameter, Lorey’s Mean Height, Trees Per Hectare). Logistic regressions identified a negative relationship between damage and height variation, elevation, slope, and aspect and a positive relationship with TPH. For plots/stands nearest to the coast and storm track height variation, TPH, QMD, and LMH consistently predicted damage levels for most species examined.
14

COMPARISON OF LOGISTIC REGRESSION TO LATEST CART TREE STRUCTURE GENERATING ALGORITHMS

MA, YUN 28 September 2005 (has links)
No description available.
15

Alternative Methodology To Household Activity Matching In TRANSIMS

Paradkar, Rajan 04 February 2002 (has links)
TRANSIMS (Transportation Analysis and Simulation System) developed at the Los Alamos National Laboratory, is an integrated system of travel forecasting models designed to give transportation planners accurate and complete information on traffic impacts, congestion, and pollution. TRANSIMS is a micro-simulation model which uses census data to generate a synthetic population and assigns activities using activity survey data to each person of every household of the synthetic population. The synthetic households generated from the census data are matched with the survey households based on their demographic characteristics. The activities of the survey household individuals are then assigned to the individuals of the matched synthetic households. The CART algorithm is used to match the households. With the use of CART algorithm a classification tree is built for the activity survey households based on some dependent and independent variables from the demographic data. The TRANSIMS model assumes activity times as dependent variables for building the classification tree. The topic of this research is to compare the TRANSIMS approach of using times spent in executing the activities as dependent variables, compared to match the alternative of using travel times for trips between activities as dependent variables i.e. to use the travel time pattern instead of activity time pattern to match the persons in the survey households with the synthetic households. Thus assuming that if the travel time patterns are the same then we can match the survey households to the synthetic population i.e. people with similar demographic characteristics tend to have similar travel time patterns. The algorithm of the Activity Generator module along with the original set of dependent variables, were first used to generate a base case scenario. Further tests were carried out using an alternative set of dependent variables in the algorithm. A sensitivity analysis was also carried out to test the affect of different sets of dependent variables in generating activities using the algorithm of the Activity Generator. The thesis also includes a detailed documentation of the results from all the tests. / Master of Science
16

Development and assessment of remotely derived variables in current southern pine beetle (Dendroctonus frontalis Zimm.) hazard mapping in North Carolina, USA

Moan, Jason Edward 08 September 2008 (has links)
The southern pine beetle (SPB) (Dendroctonus frontalis Zimm.) is one of the most destructive forest insect pests in the southeastern United States and has historically had a large impact on the forests of North Carolina. Many characteristics of a forest can contribute to SPB susceptibility including stand density, growth rate, age, soil type, and position on the landscape. This work was undertaken in an effort to assist and improve on the current federal SPB hazard modeling being conducted for North Carolina by the USDA Forest Service – Forest Health Protection's Forest Health Technology Enterprise Team (FHTET). In our study, predictive SPB susceptibility models were developed for each physiographic region in North Carolina using two variables not currently included in the FHTET modeling, mean stand age and the in-stand percentage of sawtimber-sized pines. These variables were obtained from USDA Forest Service – Forest Inventory and Analysis (FIA) data and North Carolina Forest Service historical SPB records creating a dataset of both infested and non-infested stands and the models were developed using the CART® classification tree approach. Two model-derived age classes (older than and younger than 22 years) were identified on the landscape using current Landsat 5 Thematic Mapper (TM) imagery chronosequences of disturbance index (DI) â transformed scenes to identify stand-replacing disturbances, resulting in a kappa statistic of 0.6364 for the younger than 22 year age class and 0.7778 for the older than 22 years age class. A kappa value of 1 is ideal. The CART® modeling effort produced valid models in all three physiographic regions of North Carolina, though the complexity of the piedmont model makes it impractical for use in the field. The dependent variable in the classification tree was presence or absence of SPB outbreak and the test sample error percentages were similar across regions, with errors ranging between 23.76 - 34.95 percent. Overall prediction success, based on the software's internal cross-validation procedure, was likewise comparable across the regions with 72.28 - 89.56 percent correctly predicted. Based on our modeling, stand age and percent sawtimber should be included in future FHTET SPB hazard modeling efforts for the coastal plain and mountains, respectively. Age classes can be reasonably estimated using Landsat or other multispectral imagery. / Master of Science
17

Seleção de famílias de cana-de-açúcar via árvores de decisão / Families selection through decision trees

Bernardes, Diego Paiva 15 March 2013 (has links)
Made available in DSpace on 2015-03-26T13:32:19Z (GMT). No. of bitstreams: 1 texto completo.pdf: 677917 bytes, checksum: fe42f6008c42e03314bd889ebb94ea29 (MD5) Previous issue date: 2013-03-15 / The process of selection of clones to be used as new commercial varieties is lacking in statistical methods and phytotechnical that increase the genetic gains in crop improvement programs of cane sugar. Out of five stages of the selection program to improve the RIDESA, the first one, T1, is endowed with great importance. First because it develops the remaining phases of the crop breeding program. And second because the volume of information to be analyzed is huge. Thus, if the data is not properly analyzed, good clones can be ruled out in the early stages, reducing the excellence of the program. The common strategies of selection, BLUP and BLUPIS, have the disadvantage of the necessity of weighing the whole plot. One way around this is to categorize the components of production; stalk height, stalk diameter and number of stalks, by decision trees. Through these trees, you can generate the combinations of these yield components and their production values. Using data from commercial varieties to generate the trees, it would not be necessary to weigh the entire plot, saving time and money. The aim of this study was to evaluate the categorization of yield components as selection strategy between and within families by comparing their performance with the usual methods, BLUP and BLUPIS. The algorithm used was the CART. Nonparametric by nature, it`s capable of producing binary divisions combining the explanatory variables and associating them with different response values. Data were collected from 5 experiments, installed in May 2007 in a randomized block design, with each experiment consisting of 5 blocks, 22 families and two commercial varieties. CART algorithm was effective in defining classes of yield components followed by selection of the best families with mean accuracy of 73% when compared with BLUPIS and BLUP. / O processo de seleção de clones de cana-de-açúcar é carente de métodos fitotécnicos e estatísticos que elevem os ganhos genéticos nos programas de melhoramento da cultura da cana-de-açúcar. De cinco fases de seleção do programa de melhoramento da RIDESA, a primeira é dotada de grande importância porque dela se desenvolvem as demais fases do programa e porque o volume de informações a ser analisados é enorme. Assim, caso os dados não forem corretamente analisados, pode-se descartar bons materiais logo nas primeiras fases, diminuindo a excelência do programa. As estratégias usuais de seleção, BLUP e BLUPIS, têm a desvantagem de exigir a de pesagem de toda a parcela. Uma maneira de se contornar isso é categorizar os componentes de produção; altura de colmos, diâmetro de colmos e número de colmos, via árvores de decisão. Através dessas árvores, é possível gerar as combinações desses componentes de produção e os respectivos valores de produção. Utilizando dados de testemunhas para gerar as árvores, não seria necessária a pesagem de toda a parcela, economizando tempo e recursos financeiros. O objetivo desse trabalho foi avaliar a categorização dos componentes de produção como estratégia de seleção entre e dentro de famílias através da comparação de seu desempenho com os métodos usuais, BLUP e BLUPIS. O algoritmo de árvore utilizado foi o CART. De natureza não paramétrica, esse é capaz de produzir divisões binárias combinando as variáveis explicativas e associando-as com distintos valores de resposta. Os dados foram coletados de 5 experimentos, instalados em maio de 2007, no delineamento em blocos casualizados, sendo cada experimento constituído de 5 blocos, 22 famílias e 2 testemunhas. O algoritmo CART foi eficiente em definir as classes dos componentes de produção seguido da seleção das melhores famílias no campo com acurácia média próxima de 73% quando comparado com o BLUPIS e BLUP.
18

Charakterizace analogů peptidu CART v testech in vitro a in vivo / Characterization of CART peptide analogs in vitro and in vivo

Nagelová, Veronika January 2012 (has links)
Peptide CART (cocaine- and amphetamine- regulated transcript) is a neuropeptide acting in the hypothalamus to reduce food intake (anorexigenic peptide). Despite all efforts the receptor and the mechanism of action is still unknown. This peptide has two biologically active forms, CART(55-102) and CART(61-102). Peptide CART is able to bind to pheochromocytoma cells PC12. PC12 cells differentiated in neuronal phenotype with NGF (nerve growth factor) showed a higher number of binding sites (11250 ± 2520 binding sites/cell) compared to undifferentiated cells (3600 ± 570 binding sites/cell). PC12 cells differentiated by dexamethasone to chromaffin cells showed high non-specific binding. Peptide CART contains three disulfide bridges. To clarify the importance of each disulfide bridge to maintain biological activity, analogues with one (analogue 3, 4 and 5) or two (2, 6, 7 and 8) disulfide bridges and a peptide analogue of CART (61-102), which has methionin at position 67 replaced with norleucine were synthesized. We showed that biological activity was unchanged at analogue 1 and analogue 7 containing disulfide bridges in positions 74-94 and 88-101. When investigating cell signaling in PC12 cells, we tested if peptide CART activate of c-Fos, c-Jun, phosphorylated ERK1/2, CREB, JNK and p38. CART peptide...
19

MyBookStore-eshopping for books

Chitturi, Sushma Reddy January 1900 (has links)
Master of Science / Department of Computing and Information Sciences / Daniel A. Andresen / The Web is a shopper's paradise boasting every kind of product imaginable — plus many more that are almost unimaginable. People find it easy and secure to shop online these days thereby saving time and also have more options to choose from at their fingertips. Based on this comes MyBookStore, a neat web application designed to exclusively cater the needs of students for purchasing books online. Primary focus of this application is to ease the use of searching for a particular book by the user and also navigability within the website. A sophisticated search engine has been designed in this application which filters the products based on various user criterions. Searching and viewing the details about a book is available. This also has an administrator side through which the administrator can update the website with new products, remove any of the available products, and add new categories, subcategories and products along with updating the shipping status of orders placed. This section is majorly responsible for user accounts maintenance, product maintenance as well as orders maintenance. Major emphasis of this application is to build user interactive search techniques for simplifying user needs and to provide specific products as required by the user.
20

Modélisation de l’incertitude sur les trajectoires d’avions / Uncertainty modeling on aircraft trajectories

Fouemkeu, Norbert 22 October 2010 (has links)
Dans cette thèse, nous proposons des modèles probabilistes et statistiques d’analyse de données multidimensionnelles pour la prévision de l’incertitude sur les trajectoires d’aéronefs. En supposant que pendant le vol, chaque aéronef suit sa trajectoire 3D contenue dans son plan de vol déposé, nous avons utilisé l’ensemble des caractéristiques de l’environnement des vols comme variables indépendantes pour expliquer l’heure de passage des aéronefs sur les points de leur trajectoire de vol prévue. Ces caractéristiques sont : les conditions météorologiques et atmosphériques, les paramètres courants des vols, les informations contenues dans les plans de vol déposés et la complexité de trafic. Typiquement, la variable dépendante dans cette étude est la différence entre les instants observés pendant le vol et les instants prévus dans les plans de vol pour le passage des aéronefs sur les points de leur trajectoire prévue : c’est la variable écart temporel. En utilisant une technique basée sur le partitionnement récursif d’un échantillon des données, nous avons construit quatre modèles. Le premier modèle que nous avons appelé CART classique est basé sur le principe de la méthode CART de Breiman. Ici, nous utilisons un arbre de régression pour construire une typologie des points des trajectoires des vols en fonction des caractéristiques précédentes et de prévoir les instants de passage des aéronefs sur ces points. Le second modèle appelé CART modifié est une version améliorée du modèle précédent. Ce dernier est construit en remplaçant les prévisions calculées par l’estimation de la moyenne de la variable dépendante dans les nœuds terminaux du modèle CART classique par des nouvelles prévisions données par des régressions multiples à l’intérieur de ces nœuds. Ce nouveau modèle développé en utilisant l’algorithme de sélection et d’élimination des variables explicatives (Stepwise) est parcimonieux. En effet, pour chaque nœud terminal, il permet d’expliquer le temps de vol par des variables indépendantes les plus pertinentes pour ce nœud. Le troisième modèle est fondé sur la méthode MARS, modèle de régression multiple par les splines adaptatives. Outre la continuité de l’estimateur de la variable dépendante, ce modèle permet d’évaluer les effets directs des prédicteurs et de ceux de leurs interactions sur le temps de passage des aéronefs sur les points de leur trajectoire de vol prévue. Le quatrième modèle utilise la méthode d’échantillonnage bootstrap. Il s’agit notamment des forêts aléatoires où pour chaque échantillon bootstrap de l’échantillon de données initial, un modèle d’arbre de régression est construit, et la prévision du modèle général est obtenue par une agrégation des prévisions sur l’ensemble de ces arbres. Malgré le surapprentissage observé sur ce modèle, il est robuste et constitue une solution au problème d’instabilité des arbres de régression propre à la méthode CART. Les modèles ainsi construits ont été évalués et validés en utilisant les données test. Leur application au calcul des prévisions de la charge secteur en nombre d’avions entrants a montré qu’un horizon de prévision d’environ 20 minutes pour une fenêtre de temps supérieure à 20 minutes permettait d’obtenir les prévisions avec des erreurs relatives inférieures à 10%. Parmi ces modèles, CART classique et les forêts aléatoires présentaient de meilleures performances. Ainsi, pour l’autorité régulatrice des courants de trafic aérien, ces modèles constituent un outil d’aide pour la régulation et la planification de la charge des secteurs de l’espace aérien contrôlé. / In this thesis we propose probabilistic and statistic models based on multidimensional data for forecasting uncertainty on aircraft trajectories. Assuming that during the flight, aircraft follows his 3D trajectory contained into his initial flight plan, we used all characteristics of flight environment as predictors to explain the crossing time of aircraft at given points on their planned trajectory. These characteristics are: weather and atmospheric conditions, flight current parameters, information contained into the flight plans and the air traffic complexity. Typically, in this study, the dependent variable is difference between actual time observed during flight and planned time to cross trajectory planned points: this variable is called temporal difference. We built four models using method based on partitioning recursive of the sample. The first called classical CART is based on Breiman CART method. Here, we use regression trees to build points typology of aircraft trajectories based on previous characteristics and to forecast crossing time of aircrafts on these points. The second model called amended CART is the previous model improved. This latter is built by replacing forecasting estimated by the mean of dependent variable inside the terminal nodes of classical CART by new forecasting given by multiple regression inside these nodes. This new model developed using Stepwise algorithm is parcimonious because for each terminal node it permits to explain the flight time by the most relevant predictors inside the node. The third model is built based on MARS (Multivariate adaptive regression splines) method. Besides continuity of the dependent variable estimator, this model allows to assess the direct and interaction effects of the explanatory variables on the crossing time on flight trajectory points. The fourth model uses boostrap sampling method. It’s random forests where for each bootstrap sample from the initial data, a tree regression model is built like in CART method. The general model forecasting is obtained by aggregating forecasting on the set of trees. Despite the overfitting observed on this model, it is robust and constitutes a solution against instability problem concerning regression trees obtained from CART method. The models we built have been assessed and validated using data test. Their using to compute the sector load forecasting in term to aircraft count entering the sector shown that, the forecast time horizon about 20 minutes with the interval time larger than 20 minutes, allowed to obtain forecasting with relative errors less than 10%. Among all these models, classical CART and random forests are more powerful. Hence, for regulator authority these models can be a very good help for managing the sector load of the airspace controlled.

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