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Oblique decision trees in transformed spaces.Wickramarachchi, Darshana Chitraka January 2015 (has links)
Decision trees (DTs) play a vital role in statistical modelling. Simplicity and interpretability of the solution structure have made the method popular in a wide range of disciplines. In data classification problems, DTs recursively partition the feature space into disjoint sub-regions until each sub-region becomes homogeneous with respect to a particular class. Axis parallel splits, the simplest form of splits, partition the feature space parallel to feature axes. However, for some problem domains DTs with axis parallel splits can produce complicated boundary structures. As an alternative, oblique splits are used to partition the feature space potentially simplifying the boundary structure. Various approaches have been explored to find optimal oblique splits. One approach is based on optimisation techniques. This is considered the benchmark approach, however, its major limitation is that the tree induction algorithm is computationally expensive. On the other hand, split finding approaches based on heuristic arguments have gained popularity and have made improvements on benchmark methods. This thesis proposes a methodology to induce oblique decision trees in transformed spaces based on a heuristic argument.
As the first goal of the thesis, a new oblique decision tree algorithm, called HHCART (\underline{H}ouse\underline{H}older \underline{C}lassification and \underline{R}egression \underline{T}ree) is proposed. The proposed algorithm utilises a series of Householder matrices to reflect the training data at each non-terminal node during the tree construction. Householder matrices are constructed using the eigenvectors from each classes' covariance matrix. Axis parallel splits in the reflected (or transformed) spaces provide an efficient way of finding oblique splits in the original space. Experimental results show that the accuracy and size of the HHCART trees are comparable with some benchmark methods in the literature. The appealing features of HHCART is that it can handle both qualitative and quantitative features in the same oblique split, conceptually simple and computationally efficient.
Data mining applications often come with massive example sets and inducing oblique DTs for such example sets often consumes considerable time. HHCART is a serial computing memory resident algorithm which may be ineffective when handling massive example sets. As the second goal of the thesis parallel computing and disk resident versions of the HHCART algorithm are presented so that HHCART can be used irrespective of the size of the problem.
HHCART is a flexible algorithm and the eigenvectors defining Householder matrices can be replaced by other vectors deemed effective in oblique split finding. The third endeavour of this thesis explores this aspect of HHCART. HHCART can be used with other vectors in order to improve classification results. For example, a normal vector of the angular bisector, introduced in the Geometric Decision Tree (GDT) algorithm, is used to construct the Householder reflection matrix. The proposed method produces better results than GDT for some problem domains. In the second case, \textit{Class Representative Vectors} are introduced and used to construct Householder reflection matrices. The results of this experiment show that these oblique trees produce classification results competitive with those achieved with some benchmark decision trees.
DTs are constructed using two approaches, namely: top-down and bottom-up. HHCART is a top-down tree, which is the most common approach. As the fourth idea of the thesis, the concept of HHCART is used to induce a new DT, HHBUT, using the bottom-up approach. The bottom-up approach performs cluster analysis prior to the tree building to identify the terminal nodes. The use of the Bayesian Information Criterion (BIC) to determine the number of clusters leads to accurate and compact trees when compared with Cross Validation (CV) based bottom-up trees. We suggest that HHBUT is a good alternative to the existing bottom-up tree especially when the number of examples is much higher than the number of features.
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An investigation into sustainable forest policies and practices in SyriaAl Berni, Rim Rateb January 2010 (has links)
Appreciation of how forest land can be managed in a sustainable way in arid and semi-arid zones (ASAZs) of centralized countries is limited. Accordingly, this thesis seeks to analyse the role of government and communities, including women, in the formulation and implementation of sustainable forest management (SFM) policy and practices in the semi-arid environment of Syria where such land is limited in extent (e.g. 3% forest and 57% rangeland) and yet where its high biodiversity value is of international significance. The thesis employs a variety of methods: a case study approach (Syria); a questionnaire (i.e. 142 respondents); face-to-face interviews (i.e. 26 interviewees); participant observation and secondary data. The SFM model was used to organise and analyse the influences of environmental, economic, social, cultural and political issues on the state of forest land in Syria. Three contrasting forest areas were selected for detailed analysis at local level: Al Foronloq had the Arab Institute of Forestry close by and the area had a high biodiversity value for landscape; Abo Kbeis contained key genetic resources and a number of women there had been trained in forest management and Abd Aziz Mountain was characterised by rangeland with traditional grazing plus a very arid environment. The main results obtained from census data confirmed that Syrian forest lands have diminished considerably since 1900 with regard to their geographical extent due to agricultural development, expansion of rural-urban settlements as well as of agricultural land onto Syrian forest land. On a more general level, the political issues in Syria (i.e. centralization and independency of the country) demand development of the internal resources of the country, such as agricultural production, in order to cover the needs of human maintenance. Scrutinising forest documentation and using results of face-to-face interviews, it was found that there were considerable changes in forest policies in terms of forest protection and plantation. In addition, there was a recent indication of adopting SFM principles in the case study area, largely as a result of action by agencies external to Syria at the national level, and the new role of NGOs in forest management at the local level. The increasing level of awareness of environmental problems; the capacity of institutions; community participation in natural resources management and achieving international agreements were also found to be paramount in any contracts between the Syrian government and other organisations. This thesis, at the local level, showed that respondents in the mountains (in the Abd Aziz Mountain (AAM) study area) seemed to be older, poorer, mostly with non-educated background, with more than three children, than in the Al Foronloq (AF) and Abo Kbeis (AK) study areas. Respondent groups in AAM were found to be more dependent upon forest resources than respondents in AF and AK; and they occupied land illegally because of their mission to develop agricultural activities, including grazing. The study confirmed that educated households in AF and AK use forest resources more than non-educated households. Conversely, non-educated households in AAM suffer from gaining a local income which may in turn affect their attitudes and behaviours in using forest resources; and as consequence, householders suffering from financial problems may be less aware of the importance of forest protection and try to solve their individual needs by increasing the pressures on the forest resources. The major constraints affecting the formulation and implementation of SFM policy are insufficient financial resources, inadequate management from national to regional and local levels; the limitations are also related to local communities’ attitudes and ignorance of the role of women in forest management. This thesis found that the contribution of women in the labour force at the local level was high in Lattakia (Al Foronloq study area) compared with other study areas (e.g. 32.9% in Lattakia against 13.4% in Hamah and 18.8% in Alhasake) (UNDP: Syrian Human development, 2005); although, there was a significant relationship between income level, family size and women’s contribution in forest management at the local level and no significant relationship with the educational level. On a more specific level, the role of religious faith in AK affects the contribution of women in the society and the workplace generally and in forest management in particular. Finally, the application of the SFM model in this study provided a flexible approach for analysis of complicated interactions between the government and communities. It also provided a comprehensive framework for different types of analytical purposes. Each of the three main components (issues, state and political decisionmakers) was divided into several sub-components which facilitate the explanation and identification of the complexities affecting the formulation of SFM policy and the implementation of such policy. It helped to provide a set of policy recommendations which may help to increase future community participation in forest management and reduce the influences of community pressures on forest resources in Syria.
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Effect of Substrate on Bottom-Up Fabrication and Electronic Properties of Graphene NanoribbonsSimonov, Konstantin January 2016 (has links)
Taking into account the technological demand for the controlled preparation of atomically precise graphene nanoribbons (GNRs) with well-defined properties, the present thesis is focused on the investigation of the role of the underlying metal substrate in the process of building GNRs using bottom-up strategy and on the changes in the electronic structure of GNRs induced by the GNR-metal interaction. The combination of surface sensitive synchrotron-radiation-based spectroscopic techniques and scanning tunneling microscopy with in situ sample preparation allowed to trace evolution of the structural and electronic properties of the investigated systems. Significant impact of the substrate activity on the growth dynamics of armchair GNRs of width N = 7 (7-AGNRs) prepared on inert Au(111) and active Cu(111) was demonstrated. It was shown that unlike inert Au(111) substrate, the mechanism of GNRs formation on Ag(111) and Cu(111) includes the formation of organometallic intermediates based on the carbon-metal-carbon bonds. Experiments performed on Cu(111) and Cu(110), showed that a change of the balance between molecular diffusion and intermolecular interaction significantly affects the on-surface reaction mechanism making it impossible to grow GNRs on Cu(110). It was demonstrated that deposition of metals on spatially aligned GNRs prepared on stepped Au(788) substrate allows to investigate GNR-metal interaction using angle-resolved photoelectron spectroscopy. In particular intercalation of one monolayer of copper beneath 7-AGNRs leads to significant electron injection into the nanoribbons, indicating that charge doping by metal contacts must be taken into account when designing GNR/electrode systems. Alloying of intercalated copper with gold substrate upon post-annealing at 200°C leads to a recovery of the initial position of GNR-related bands with respect to the Fermi level, thus proving tunability of the induced n-doping. Contrary, changes in the electronic structure of 7-AGNRs induced by the deposition of Li are not reversible. It is demonstrated that via lithium doping 7-AGNRs can be transformed from a semiconductor into a metal state due to the partial filling of the conduction band. The band gap of Li-doped GNRs is reduced and the effective mass of the conduction band carriers is increased.
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La spectrométrie de masse haute résolution : application à la FT-ICR bidimensionnelle et à la protéomique dans les domaines de l’archéologie et la paléontologie / High Resolution Mass Spectrometry : Application to Two-Dimensional FT-ICR and Proteomics in the Fields of Archeology and PaleontologyBray, Fabrice 12 December 2017 (has links)
La spectrométrie de masse est une méthode d’analyse qui permet de travailler sur une large gamme d’échantillons. Elle est utilisée dans de nombreux domaines de recherche comme la chimie analytique, la protéomique, la lipidomique et la métabolomique…Dans un premier temps, mon travail s’est focalisé sur le développement d’une méthode indépendante d’analyse de données par spectrométrie de masse à transformée de Fourier bidimensionnelle. Pour augmenter la résolution en première dimension, une analyse FT-ICR 2D avec un échantillonnage non uniforme (NUS) a été développée. L’augmentation de la résolution dans la première dimension a permis l’obtention d’une haute résolution pour les ions précurseurs. La FT-ICR 2D a été utilisée avec succès pour l’analyse de triacylglycérols contenus dans du plasma mais aussi pour l’analyse d’échantillons archéologiques.Dans un second temps, une stratégie protéomique conjointe bottom-up et top-down a été appliquée à l’analyse d’échantillons archéologiques et paléontologiques à partir d’ossements ou de céramiques. Le développement d’une méthodologie bottom-up, a permis à partir d’ossements archéologiques d’espèces inconnues l’identification des protéines et leurs modifications chimiques. Cet ossement a pu être attribué comme appartenant à l’espèce Homo sapiens. Une analyse top-down a été utilisée pour l’analyse d’échantillons archéologiques. Pour la première fois, une protéine (la caséine de lait) a été identifiée dans un échantillon archéologique d’amphore de l’époque de l’empereur Claude (1er siècle de notre ère) grâce la détection de grands fragments de caséine. / Mass spectrometry is a method of analysis which works on a wide range of sample types. It is used in many research fields such as analytical chemistry, proteomics, lipidomics and metabolomics...Firstly, my work was dedicated to the development of an independent data analysis methodology based on two-dimensional Fourier transform mass spectrometry. For increasing the resolution on the first dimension a 2D FT-ICR analysis with non-uniform sampling was developed. The resolution increase in the first dimension leading to high resolution for the precursor ions. The 2D FT-ICR has been successfully applied for the analysis of triacylglycerol contained on plasma and also for archaeological samples. This methodology led to 2D maps allowing a rapid classification of plants or animals samples.Secondly, a joint bottom-up and top-down proteomics strategy was applied for the analysis of archaeological and paleontological samples from bones or ceramics. The development of a bottom-up methodology, allowed the identification of proteins and their chemical modifications from archeological bones. These bones have been attributed to Homo sapiens. The development of a top-down methodology was applied to the analysis of archaeological ceramic. For the first time, a protein (milk casein) was identified in an archaeological sample of an amphora from Claudius emperor era (1st century A.D) via the detection of large fragments of casein. This first application of the top down proteomics showed that new information can be provided such as the in situ molecular degradation.
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Language policies on the ground : parental language management in urban Galician homesNandi, Anik January 2017 (has links)
Recent language policy and planning research reveals how policy-makers endorse the interests of dominant social groups, marginalise minority languages and perpetuate systems of sociolinguistic inequality. In the Castilian-dominated Galician linguistic landscape, this study examines the rise of grassroots level actors or agents (i.e. parents, family members, and other speakers of minority Galician) who play a significant role in interpreting and implementing language policy on the ground. The primary focus of this study is to investigate the impact of top-down language policies inside home domain, it looks at how the individual linguistic practices and ideologies of Galician parents act as visible and/or invisible language planning measures influencing their children’s language learning. However, these individual linguistic ideologies and language management decisions are difficult to detect because they are implicit, subtle, informal, and often hidden from the public eye, and therefore, frequently overlooked by language policy researchers and policy makers. Drawing from multiple ethnographic research methods including observations, in-depth fieldwork interviews, focus group discussions and family language audits with thirty-two Galician parents, this study attempts to ascertain whether these parents can restore intergenerational transmission of Galician and if their grassroots level interrogation of the dominant discourse could lead to bottom-up language policies.
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Does Fascia Bowen therapy improve neuromuscular function and psychological well-being in males aged 8-11 (at primary school) with dyspraxia/developmental coordination disorder?Morgan-Jones, Melanie January 2015 (has links)
Background: Dyspraxia, also included under the term Developmental Coordination Disorder (DCD), is a condition characterised by an impairment in motor skills function which impacts negatively on other aspects of daily living such as athletic capability, handwriting, self-esteem and social interaction. However, no effective therapy currently exists to address all of these issues within this group. The aim of the present study therefore was to investigate whether a complementary therapy, called Fascia Bowen therapy, would improve neuromuscular function and psychological wellbeing in males aged 8-11 (at Primary School) diagnosed with this condition. Methods: A group of 10 participants meeting the criteria of 15th centile or below in motor skills functioning, received a Fascia Bowen therapy treatment session from a qualified Fascia Bowen practitioner each week for 6 weeks. All participants’ motor skills function were assessed by an occupational therapist before and after the end of the intervention using the Motor Skills Assessment Battery for Children test (MABC-2). Additionally, parents, teachers and participants completed questionnaires measuring self-esteem, social skills, social interaction, behaviour and scholastic function before and after the intervention. Results: The participants showed significant improvement in neuromuscular function over time using the MABC-2. However, no significant changes were shown in the other measures of functioning. Although parents did provide some anecdotal reports about positive changes in real life, these were not reflected in the measures. The results suggest that while improvements were shown as significant in the motor domain, which was the focus of the therapy, the results did not translate to other domains of life over time. 13 Conclusions: Further research is necessary to test the efficacy of the treatment’s effects using a larger sample, a control group and a longer intervention timescale. A six week intervention period may not be sufficient to show significant changes in self-esteem, social skills, social interaction, behaviour and scholastic functions which have deep-rooted constructs developed over many years. These may therefore take a long time to change.
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Developing a programme of support for teacher leadership in EgyptEltemamy, Amina January 2018 (has links)
In Egypt, the school educational system has been suffering a deteriorating quality over the last few decades. Since the revolution that took place in Egypt in 2011, political tensions and conflicts have consumed so much energy and time, making it hard for Egyptians to focus on development. Therefore, through this doctoral study that follows an action based methodology, I aim to contribute to the current efforts to improve the Egyptian educational system. In this study, I introduced an intervention that draws upon the principles of school improvement, reform strategies and non-positional teacher leadership. This is done through adopting and adapting the ‘teacher-led development work’ (TLDW) approach. In this study, a group of 50 teachers from four different Egyptian schools took part in the programme for one academic year. Through this programme I supported them to lead innovations in their classrooms and schools as a whole. Each teacher/participant was expected to initiate and lead a development project that improves teaching and learning in their schools, and other teachers could benefit from as well. Data was collected throughout the academic year to continuously monitor and adapt the programme, and to explore what the programme made possible and the conditions that made it possible. The programme usefully supported teachers in taking action that had a positive impact on the students, teachers and school as a whole. However, the most significant impact observed was on the participating teachers themselves: their professionality, self-confidence and self-efficacy that underpinned growth in their own skills and pedagogic repertoires. There were a set of conditions that were required for this programme to have an impact. Practitioners and policy makers interested in educational reform through teachers could benefit from considering these factors in their own development.
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Previsão de demanda de um prédio universitário por redes neurais artificiais / Load forecasting of a university building by artificial neural networksCarvalho, Monara Pereira da Rosa [UNESP] 20 January 2017 (has links)
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Previous issue date: 2017-01-20 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / This work analysis load data from desegregated levels that presented difficulties to load forecasting with several methods due to variation in electrical energy consumption. The application proposed in this work is short-term load forecasting to a university building by GRNN (General Regression Neural Network) considering the bottom up approach and using a moving average filter to deal with the missing or wrong data. It is presented the system that provides the data as well as the methods used for pre-processing and realize the forecasting. The results are evaluated by MAPE (Mean Absolute Perceptual Error) and are considered good when compared with other methods. / Este trabalho destaca a análise de dados provenientes de locais com níveis de consumo mais desagregados que apresentam dificuldades para previsões de demanda com vários métodos devido à alta variação no consumo de energia elétrica. Apresenta-se resultados de previsões de demanda de curto prazo da energia elétrica consumida em um bloco de uma universidade por meio da rede neural de regressão generalizada (GRNN), utilizando a abordagem de modelagem de dados de baixo para cima e tratamento de ruídos e dados faltantes no banco de dados através da aplicação de um filtro de médias móveis. É apresentado o local que fornece as informações para os estudos e a etapa de pré-processamentos dos dados. Foi possível analisar a assertividade das previsões de acordo com o cálculo do MAPE, mostrando vantagens ao se comparar a outros métodos utilizados para os mesmos fins.
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READ 180 Evaluation: Balanced Literacy in a Low-Income, Underperforming Urban High SchoolLombardi, Daniel 01 January 2015 (has links)
This study investigated the effectiveness of the READ 180 balanced literacy program in addressing the problem of low reading achievement among urban minority high school students. Research has shown low reading achievement to negatively impact academic and economic success. Holdaway's theory of natural literacy, which suggests reading instruction should be purposeful and realistic, supports READ 180 as a remedial intervention. The specific purpose of the study was to evaluate READ 180 in relation to improving classroom reading achievement, standardized language arts test scores, and graduation rates among students in a low-income, high-minority urban high school. Subjects were 2 cohorts of students consisting of 619 enrolled in READ 180 during the school year of 2007-2008 and 358 students enrolled in READ 180 during the school year of 2010-2011 at an urban high school in New Jersey. Following a goals-based program evaluation design, a paired difference t test was used to evaluate classroom reading achievement; a chi-square test was used to evaluate graduation rates; and a multiple regression analysis controlling for initial status was used to evaluate performance on the standardized language arts test. Findings indicated moderate improvement in classroom reading achievement, no improvement in graduation rates, and strong improvement in standardized test scores only for English learners. Results suggested that a balanced literacy program such as READ 180 may provide effective reading remediation for English learners in low-income urban areas, thereby promoting social change through increased academic success and upward economic mobility.
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An analysis concerning three organisations work with reducing child labour : – A case study within Peru’s mining industrySheikholeslamzadeh, Sanaz, Bergvall Bark, Marie January 2008 (has links)
<p>This thesis aim to describe and analyze different organisations’ work with reducing child labour. In order to understand the complex matter of child labour, a case study concerning children’s situation within the mining industry in Peru has been made. The first part of the thesis has been designed to be an introduction to the matter, with a description of the mining industry in Peru and the situation of child labour. The two following parts are more analytic in character. The second and third part discusses how the Millennium Development Goals (MDGs) can be used as an instrument of reducing child labour. Further, top down and bottom up-theories will be discussed as different approaches and working methods for organisations.</p><p>In addition to find the answers to our questions, interviews have been conducted with employees of the organisations (ILO, UNICEF and Save the Children), articles and literature have been analyzed and finally Internet have contributed with information about child labour, Peru, the organisations, theories and the MDGs.</p><p>This study claims that child labour is a complex matter and one possible solution to reduce it can be through promoting education. This can only be viable if organisations work together with governments, using a combination of top down and bottom up approaches.</p>
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