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Programa de manejo fronteiras para o Parque Estadual Xixová-Japuí-SP.; Park boundaries management program for Xixová-Japuí State Park in São Paulo.

Oliva, Adriana
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 30/10/2003 Português
Relevância na Pesquisa
36.35%
Este estudo propôs e testou um roteiro metodológico, baseado em princípios técnicos e científicos, visando à delimitação da zona de amortecimento de unidades de conservação (UCs) de proteção integral, bem como à estruturação de um programa de manejo específico, denominado “Fronteiras”. O Programa de Manejo Fronteiras tem como principal objetivo estabelecer diretrizes e estratégias para tratar das questões que envolvem a implementação e a gestão da zona de amortecimento. Utilizando a metodologia de estudo de caso, associada a uma adaptação do método da estrutura hierárquica que é baseado na formulação de princípios, critérios e indicadores como ferramenta para promover o manejo adequado e a manutenção das funções da UC, o Parque Estadual Xixová-Japuí (PEXJ), com uma área de 901 ha, localizado nos municípios de São Vicente e Praia Grande–SP, foi escolhido como unidade de análise para execução das seis etapas previstas no referido roteiro metodológico. A partir da avaliação da execução do trabalho e dos resultados obtidos foi possível, além de criar uma referência concreta para a discussão e o aprimoramento dos procedimentos que podem ser utilizados na delimitação e na gestão da zona de amortecimento...

Industry analysis of the high frequency trading industry: an assessment of the industry boundaries, environment and strategic options

Vieira, Paulo Sérgio Coelho
Fonte: Fundação Getúlio Vargas Publicador: Fundação Getúlio Vargas
Tipo: Dissertação
Português
Relevância na Pesquisa
36.45%
O Mercado Acionário Americano evoluiu rapidamente na última década. Este tornou-se uma arquitetura aberta em que participantes com tecnologia inovadora podem competir de forma eficaz. Várias mudanças regulatórias e inovações tecnológicas permitiram mudanças profundas na estrutura do mercado. Essas mudanças, junto com o desenvolvimento tecnológico de redes de alta velocidade, agiu como um catalisador, dando origem a uma nova forma de negociação, denominada Negociação em Alta Frequência (HFT). As empresas de HFT surgiram e se apropriaram em larga escala do negócio de formação de mercado, no fornecimento de liquidez. Embora HFT tem crescido massivamente, ao longo dos últimos quatro anos, HFT perdeu rentabilidade significativamente, uma vez que mais empresas aderiram ao setor reduzindo as margens. Portanto, diante deste contexto, esta tese buscou apresentar uma breve revisão sobre a atividade de HFT, seguida de uma análise dos limites deste setor, bem como, das características do macroambiente do HFT. Para tanto, a tese realizou uma extensa revisão do histórico literário, documentos públicos qualitativos, tais como, jornais, atas de reunião e relatórios oficiais. A tese empregou um ferramental de análise...

Optimization of neural classifiers based on bayesian decision boundaries and idle neurons pruning

Silvestre, Miriam Rodrigues; Ling, Lee Luan
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Conferência ou Objeto de Conferência Formato: 387-390
Português
Relevância na Pesquisa
36.35%
In this article we describe a feature extraction algorithm for pattern classification based on Bayesian Decision Boundaries and Pruning techniques. The proposed method is capable of optimizing MLP neural classifiers by retaining those neurons in the hidden layer that realy contribute to correct classification. Also in this article we proposed a method which defines a plausible number of neurons in the hidden layer based on the stem-and-leaf graphics of training samples. Experimental investigation reveals the efficiency of the proposed method. © 2002 IEEE.

Outlining precision boundaries among areas with different variability standards using magnetic susceptibility and geomorphic surfaces

Matias, Sammy S. R.; Marques Júnior, José; Siqueira, Diego S.; Pereira, Gener T.
Fonte: Associação Brasileira de Engenharia Agrícola Publicador: Associação Brasileira de Engenharia Agrícola
Tipo: Artigo de Revista Científica Formato: 695-706
Português
Relevância na Pesquisa
36.45%
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); There is an increasing demand for detailed maps that represent in a simplified way the knowledge of the variability of a particular area or region maps. The objective was to outline precision boundaries among areas with different accuracy variability standards using magnetic susceptibility and geomorphic surfaces. The study was conducted in an area of 110 ha, which identified three compartment landscapes based on the geomorphic surfaces model. To determinate pH, organic matter, phosphorus, potassium and magnesium, the total sand and clay, 514 soil samples were collected at depths of 0-0.20 m and 0.60-0.80 m. The sum of base, cationic exchange capacity and base saturation were calculated and the magnetic susceptibility was evaluated in the laboratory using a system based on a balance of analytical precision method. Geomorphic surfaces identification allowed setting specific management areas (locations with maximum homogeneity of soil attributes). The map of spatial variability of magnetic susceptibility can be used to validate the precise boundaries among geomorphic surfaces identified in the field and infer the variability of clay content and soil base saturation.; Existe uma demanda cada vez maior por mapas detalhados que representem de maneira simplificada o conhecimento da variabilidade de determinada área ou região. O objetivo do trabalho foi delinear limites de precisão entre áreas com diferentes padrões de variabilidade utilizando suscetibilidade magnética e superfícies geomórficas. O trabalho foi realizado em uma área de 110 ha...

Fronteiras sociais e a educação das crianças em famílias de alta renda; Social boundaries and the education of children in high income families

Karen Tereza Marcolino Polaz
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 20/12/2012 Português
Relevância na Pesquisa
36.45%
Esta pesquisa investiga os processos de construção de fronteiras sociais pelas famílias de alta renda em relação a outros grupos e como essas fronteiras se mantêm ao longo do tempo. Para tanto, analisou-se as práticas de educação de famílias associadas ao clube mais seletivo, em termos econômicos, de uma grande cidade do interior de São Paulo. Foram focalizados, particularmente, os filhos envolvidos no curso de equitação e nas atividades competitivas realizadas pelo departamento de hipismo. O trabalho de campo consistiu na realização de observações tanto das aulas, quanto das provas realizadas no clube e entrevistas aprofundadas e semi-estruturadas com mães, pais e filhos e, também, alguns funcionários. O clube é visto, neste trabalho, como um dos lugares onde os associados parecem estar "entre si" e onde suas crianças podem ser expostas à aprendizagem dos valores, modos de vida, sensibilidades, habilidades, percepções próprias ao grupo social a que são destinadas a pertencer. Os resultados mostram como as experiências educativas, incluindo a passagem por esse "esporte de elite", contribuem para a constituição de uma maneira de perceber a si e aos outros que pode estar diretamente ou não relacionada às formas concretas de agir sobre o espaço social à sua volta.; This research investigates the processes involved in the formation of social boundaries in high income families in relation to other groups and how these boundaries are maintained over the course of time. The educational practices of families associated with the most selective club...

Remote Sensing and Digital Databases to Recovery Terrestrial Boundaries in West Africa – Cape Roxo Region

Sousa, Adélia; Melo, Ana Raquel; Nunes, Maria do Carmo; Cabral, Ana; Costa, Fernando; Morgado, Ana
Fonte: Universidade de Évora Publicador: Universidade de Évora
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
36.35%
This case study focuses on borderlands located in Guinea Bissau, more specifically on the borderland of Cape Roxo region, with a controversial geographic location which have been raising great interest and several disputes, mainly due to the lack of geographical information. This study intends to contribute to clarify the problem combining geographical information and multitemporal analysis to define the exact position of some boundary beacons. The geographical information used, includes all available data, from old and actual maps and technical reports to most recent data obtained from new geospatial technologies. Historic and geographic information, describing the Guinea Bissau boundaries, combined with ancient aerial photographs (1950-1960) and recent high spatial resolution satellite images (2013), WorldView-2, are used in a Geographic Information System (GIS) to perform the multitemporal study. The spatial resolution of WorldView-2 images was improved using several pan-sharpening algorithms to combine multispectral and panchromatic bands in order to obtain a pansharpened image with higher spatial resolution. This procedure enhances the spatial information improving the interpretation of terrain features. Multitemporal analysis detected changes in coastal landforms...

Geospatial Technologies Applied to International Boundaries – the Case Study of Guinea Bissau

Nunes, Maria do Carmo; Sousa, Adélia; Pinto, João; Morgado, Ana; Costa, Fernando; Cabral, Ana; Bock, Augusto; Cassamá, Viriato
Fonte: Universidade de Évora Publicador: Universidade de Évora
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
36.45%
Modern geospatial technologies applied to frontiers involve remote sensing data, namely satellite imagery, orthophoto or orthoimages, global navigation technology (GPS/GNSS), as well as Geographical Information System (GIS) tools, which have been used during the last decade for boundary delimitation, demarcation or revision. This paper intends to present the case study of Guinea Bissau boundary which was the first African Portuguese colonies to settle its boundaries. It was delimitated by a Franco– Portuguese convention signed in Paris on May 12, 1886, and ratified later in Lisbon, on August 31, 1887. The demarcation was completed between 1900 and 1905 and recorded in memoranda prepared by the commissioners. For historical reasons Tropical Research Institute (IICT) concentrates a unique, vast and diverse amount of information concerning the borders of those countries. The scope of this research is to explore new methodologies and approaches to study frontiers, making use of geospatial technologies. A Boundary Geographical Information System (BGIS) is being developed based on GIS technology which is a powerful tool to integrate various datasets, visualize, analyze and model spatial and territorial specificities. Historicaldiplomatic information will be articulated with the geospatial data...

Outlining precision boundaries among areas with different variability standards using magnetic susceptibility and geomorphic surfaces

Matias,Sammy S. R.; Marques Júnior,José; Siqueira,Diego S.; Pereira,Gener T.
Fonte: Associação Brasileira de Engenharia Agrícola Publicador: Associação Brasileira de Engenharia Agrícola
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2014 Português
Relevância na Pesquisa
36.45%
There is an increasing demand for detailed maps that represent in a simplified way the knowledge of the variability of a particular area or region maps. The objective was to outline precision boundaries among areas with different accuracy variability standards using magnetic susceptibility and geomorphic surfaces. The study was conducted in an area of 110 ha, which identified three compartment landscapes based on the geomorphic surfaces model. To determinate pH, organic matter, phosphorus, potassium and magnesium, the total sand and clay, 514 soil samples were collected at depths of 0-0.20 m and 0.60-0.80 m. The sum of base, cationic exchange capacity and base saturation were calculated and the magnetic susceptibility was evaluated in the laboratory using a system based on a balance of analytical precision method. Geomorphic surfaces identification allowed setting specific management areas (locations with maximum homogeneity of soil attributes). The map of spatial variability of magnetic susceptibility can be used to validate the precise boundaries among geomorphic surfaces identified in the field and infer the variability of clay content and soil base saturation.

Boundaries of Visual Motion

Rubin, John M.; Richards, W.A.
Fonte: MIT - Massachusetts Institute of Technology Publicador: MIT - Massachusetts Institute of Technology
Formato: 29 p.; 2221920 bytes; 1734520 bytes; application/postscript; application/pdf
Português
Relevância na Pesquisa
36.57%
A representation of visual motion convenient for recognition shouldsmake prominent the qualitative differences among simple motions. Wesargue that the first stage in such a motion representation is to makesexplicit boundaries that we define as starts, stops, and forcesdiscontinuities. When one of these boundaries occurs in motion, humansobservers have the subjective impression that some fleeting,ssignificant event has occurred. We go farther and hypothesize that onesof the subjective motion boundaries is seen if and only if one of oursdefined boundaries occurs. We enumerate all possible motion boundariessand provide evidence that they are psychologically real.

Navigating Racial Boundaries: The One-Drop Rule and Mixed-Race Jamaicans in South Florida

Placide, Sharon E
Fonte: FIU Digital Commons Publicador: FIU Digital Commons
Tipo: Artigo de Revista Científica Formato: application/pdf
Português
Relevância na Pesquisa
36.45%
Like many West Indians, mixed-race Jamaican immigrants enter the United States with fluid notions about race and racial identifications that reflect socio-political events in their home country and that conflict with the more rigid constructions of race they encounter in the U.S. This dissertation explores the experiences of racially mixed Jamaicans in South Florida and the impact of those experiences on their racial self-characterizations through the boundary-work theoretical framework. Specifically, the study examines the impact of participants’ exposure to the one-drop rule in the U.S., by which racial identification has been historically determined by the existence or non-existence of black forebears. Employing qualitative data collected through both focus group and face-to-face semi-structured interviews, the study analyzes mixed-race Jamaicans’ encounters in the U.S. with racial boundaries, and the boundary-work that reinforces them, as well their response to these encounters. Through their stories, the dissertation examines participants’ efforts to navigate racial boundaries through choices of various racial identifications. Further, it discusses the ways in which structural forces and individual agency have interacted in the formation of these identifications. The study finds that in spite of participants’ expressed preference for non-racialism...

Grain boundaries as microreactors during reactive fluid flow: experimental dolomitization of a calcite marble

Etschmann, B.; Brugger, J.; Pearce, M.A.; Ta, C.; Brautigan, D.; Jung, M.; Pring, A.
Fonte: Springer Berlin Heidelberg Publicador: Springer Berlin Heidelberg
Tipo: Artigo de Revista Científica
Publicado em //2014 Português
Relevância na Pesquisa
36.57%
Limestone dolomitization is an example of a fluid-induced mineralogical transformation that commonly affects extensive rock volumes. To understand the mechanisms enabling these efficient replacement reactions, we investigated experimentally the dolomitization of a fractured calcite marble under flow-through conditions at mild hydrothermal conditions. Contrary to most earlier studies of coupled dissolution reprecipitation reactions that were conducted using small, individual grains, in this study, the integrity of the rock was preserved, so that the experiment explored the links between flow in a fracture and fluid–rock interaction. In these experiments, grain boundaries acted as microreactors, in which a Mg-poor ‘protodolomite’ formed initially, and then transformed into dolomite. The difficulty in nucleating dolomite played a key role in controlling the evolution of the porosity, by allowing for (1) initial dissolution along grain boundaries, and (2) formation of coarse porosity at the reaction interface. This porosity evolution not only enabled the reaction to progress efficiently, but also controlled the mineralogy of the system, as shown by brucite replacing calcite near the fracture once the fluid along calcite grain boundaries became sufficiently connected to the fluid flowing through the fracture. This study illustrates the role of grain boundaries...

Hierarchical Spatial Reasoning theory and GIS technology applied to the automated delineation of administrative boundaries

Escobar Martínez, Francisco Javier; Eagleson, Serryn; Williamson, Ian
Fonte: Universidade de Alcalá Publicador: Universidade de Alcalá
Tipo: Artigo de Revista Científica Formato: application/pdf
Português
Relevância na Pesquisa
36.57%
Throughout history, humankind has segmented and delineated the geographic environment in various ways to support administrative, political and economic activities. To date, the majority of spatial boundaries have been constructed in an uncoordinated manner with individual organisations generating individual boundaries to meet their own specific needs. As a result of this lack of coordination, there is a fragmentation of information over a series of boundary units, which not only limits the potential uses for data collected, but also the scope of analysis possible between boundary layers. The proposed solution outlined in this research involves the reorganisation of the spatial environment based on Hierarchical Spatial Reasoning (HSR) and the application of a GIS-based algorithm for the automated delineation of boundaries. By using this approach, it is expected that administrative boundaries can be formed through the aggregation of smaller units. This proposed system is focussed towards facilitating rapid and efficient cross analysis of data sets.

Domain Boundaries of the 5x5 DAS Reconstruction

Mark, Andrew Gonchee
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
Português
Relevância na Pesquisa
36.7%
Steps on surfaces have long been explored for their own sake, and exploited as growth mediators. However, another type of linear surface defect - the domain boundary - has been largely neglected. Here we introduce domain boundaries of the 5x5 dimer-adatom-stacking fault reconstruction, explore their properties and demonstrate that they too can be used to mediate growth in a useful manner. When a thin layer of Ge is grown on Si(111) lattice strain induces the overlayer to reconstruct as Ge5x5. Using solid phase epitaxy, many domains of 5x5 can be grown. The domain interiors have excellent order, and with careful annealing, the boundaries that separate them are straight and uniform. Well-ordered boundaries propagate along the two high symmetry directions <1 -1> or <1 1> and are called A-type or B-type respectively. Boundaries of the second type are unique to Ge5x5. Registration with the substrate restricts the misfit between domains to discrete possibilities which are labeled according to a modified version of the system used for domain boundaries of Si(111)7x7. The distribution of observed boundary types is strongly peaked and reflects the relative energies of boundaries of different character. The expanded labeling scheme can be used to sketch the kinetic processes which lead to the distribution peaks. The dominant boundary by far is the one known as B[-2 2]...

Water-related citizens' complaints on a coastal wet land area: exploring the influence of local administrative boundaries

Carvalho, Daniela; Fidélis, Teresa
Fonte: CESAM – Department of Environment & Planning, University of Aveiro Publicador: CESAM – Department of Environment & Planning, University of Aveiro
Tipo: Conferência ou Objeto de Conferência
Português
Relevância na Pesquisa
36.45%
This paper explores the water-related citizens’ complaints submitted to the municipalities surrounding ‘Ria de Aveiro’, a natural lagoon located in the center of Portugal close to the Atlantic coast, and is aimed at analyzing how local administrative boundaries might influence the frequency, typologies and territorial pattern of complaints. It also analyzes the frequency of water-related complaints in relation to other environmental problems raised by local population. The proposed analysis assesses how the existence of such a large water territory that ‘Ria de Aveiro’ is, influences the typologies of water-related complaints and the propensity of the population to complain about problems specifically related to the quality of this area. It also analyzes the relationship between the extent of the water body of ‘Ria the Aveiro’ within each municipality and the frequency of water-related complaints. The paper is organized into four sections. The first presents a brief literature review about citizen environmental complaints and their relevance for environmental and water resources governance, highlighting the role played by different sorts of stakeholders involved. The second section describes the case study and the methodology adopted. The results of the empirical study are presented in the third section with emphases given on the actors involved...

The Early Detection of Motion Boundaries

Spoerri, Anselm
Fonte: MIT - Massachusetts Institute of Technology Publicador: MIT - Massachusetts Institute of Technology
Formato: 98 p.; 6011802 bytes; 4691342 bytes; application/postscript; application/pdf
Português
Relevância na Pesquisa
36.52%
This thesis shows how to detect boundaries on the basis of motion information alone. The detection is performed in two stages: (i) the local estimation of motion discontinuities and of the visual flowsfield; (ii) the extraction of complete boundaries belonging to differently moving objects. For the first stage, three new methods are presented: the "Bimodality Tests,'' the "Bi-distribution Test,'' and the "Dynamic Occlusion Method.'' The second stage consists of applying the "Structural Saliency Method,'' by Sha'ashua and Ullman to extract complete and unique boundaries from the output of the first stage. The developed methods can successfully segment complex motion sequences.

Almost sure relative stability of the overshoot of power law boundaries

Doney, R A; Maller, Ross
Fonte: Plenum Publishing Corporation Publicador: Plenum Publishing Corporation
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
36.52%
We give necessary and sufficient conditions for the almost sure relative stability of the overshoot of a random walk when it exits from a two-sided symmetric region with curved boundaries. The boundaries are of power-law type, ±rn b , r > 0, n = 1, 2,...

Calculation of band boundaries of feasible solutions obtained by Multivariate Curve Resolution–Alternating Least Squares of multiple runs of a reaction monitored by NIR spectroscopy

Garrido, M.; Larrechi, M. S.; Rius, F. X.; Tauler Ferré, Romà
Fonte: Elsevier Publicador: Elsevier
Tipo: Artículo Formato: 22195 bytes; application/pdf
Português
Relevância na Pesquisa
36.57%
10 pages, 7 figures, 1 table.-- Available online Nov 6, 2004.; This study describes a method for calculating the band boundaries of feasible solutions for spectra and concentration profiles obtained by Multivariate Curve Resolution–Alternating Least Squares (MCR–ALS) analysis of a spectroscopic NIR data set. The data set is obtained by monitoring in situ the model reaction between phenyl glycidyl ether (PGE) and aniline. As this system happened to be rank-deficient, the resolution strategy used matrix augmentation. The calculation of band boundaries of feasible solutions is extended here to the simultaneous analysis of multiple data matrices. The boundaries were obtained by a non-linear constrained non-linear optimisation. The influence that the number and type of data matrices in the simultaneous analysis have on the amplitude of band boundaries is also discussed.; The authors would like to acknowledge the economic support provided by the MCyT (project No. BQU 2003-01142).; Peer reviewed

Education and linguistic boundaries in Québec : student representations and pedagogical reflections from a critical perspective

Annie Pilote; Marie-Odile Magnan; Cynthia Groff
Fonte: Universidade Autônoma de Barcelona Publicador: Universidade Autônoma de Barcelona
Tipo: Artigo de Revista Científica Formato: application/pdf
Publicado em //2011 Português
Relevância na Pesquisa
36.45%
Relations between francophones and anglophones in Québec City reflect historical struggles and changing power relations between the groups. Using a constructivist and interactionist approach to identity and ethnicity, we examine the role of English language schools in intergroup relations. We present findings from two qualitative studies conducted with youth who attended English language schools in Québec City, showing how the school system contributes to the (re)production of linguistic boundaries. The boundaries evident between language groups, as illustrated in student drawings and memories, reflect complex power relations between the groups. Taking into account these power relations and with reference to previous initiatives for addressing intergroup relations, we propose a pedagogical approach that incorporates the tools of critical pedagogy to improve intergroup relations in social contexts such as Québec City. Pedagogical activities using this critical approach would lead students to challenge power relations and intergroup categorization between anglophones and francophones in Québec.; Les relations entre les francophones and les anglophones dans la ville de Québec sont le reflet de tensions historiques et de changements dans les rapports de pouvoirs entre les groupes. À partir d'une approche constructiviste et interactionniste de l'identité et de l'ethnicité...

Importance of Low-Angle Grain Boundaries in YBa2Cu3O7-? Coated Conductors

Durrell, John H.; Rutter, Noel Anthony
Fonte: Institute of Physics Publishing Publicador: Institute of Physics Publishing
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
36.67%
Over the past ten years the perception of grain boundaries in YBa2Cu3O7-? conductors has changed greatly. They are no longer a problem to be eliminated but an inevitable and potentially favourable part of the material. This change has arisen as a consequence of new manufacturing techniques which result in excellent grain alignment, reducing the spread of grain boundary misorientation angles. At the same time there is considerable recent evidence which indicates that the variation of properties of grain boundaries with mismatch angle is more complex than a simple exponential decrease in critical current. This is due to the fact that low-angle grain boundaries represent a qualitatively different system to high angle boundaries. The time is therefore right for a targetted review of research into low-angle YBa2Cu3O7-? grain boundaries. This article does not purport to be a comprehensive review of the physics of grain boundaries as found in YBa2Cu3O7-? in general; for a broader overview we would recommend that the reader consult the comprehensive review of Hilgenkamp and Mannhart (Rev. Mod. Phys., 74, 485, 2002). The purpose of this article is to review the origin and properties of the low-angle grain boundaries found in YBa2Cu3O7-? coated conductors both individually and as a collective system.; EPSRC

The Properties of Grain Boundaries in YBa2Cu3O7-d

Ransley, James
Fonte: University of Cambridge; Deparment of Materials Science and Metallurgy Publicador: University of Cambridge; Deparment of Materials Science and Metallurgy
Tipo: Thesis; Doctoral Formato: 16094161 bytes; application/pdf
Português
Relevância na Pesquisa
36.69%
Grain boundaries form the basis of an important Josephson junction technology in the cuprates and also limit the superconducting critical currents attainable in practical, polycrystalline materials. An improved understanding of these defects is therefore important for applications. The status of the current understanding of cuprate grain boundaries is summarised and experimental investigations are presented, focusing on the less well understood high angle boundaries. Measurements of the capacitance of grain boundaries in the overdoped superconductor Y1-xCaxBa2Cu3O7-8, were performed as a function of the calcium content, using the Josephson coupling across the boundaries. Particular care was taken to eliminate the e ects of heating and stray capacitance due to the substrate. The e ect of thermal noise was also assessed. These measurements provide important information about the area and the width of the grain boundaries, that highlights their inhomogeneous nature. A new technique was applied to measure the normal state properties of YBa2Cu3O7-8 grain boundaries above the critical temperature. Since the resistance of the adjacent material at high temperatures is comparable to, or greater than that of the grain boundary...