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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.
91

Ecological significance of the environmental heterogeneity between the upper and lower surfaces of a single leaf as a determinant of acarine predator-prey relationship / 葉の上下面における環境異質性がダニの捕食-被食関係に及ぼす影響

Sudo, Masaaki 24 March 2014 (has links)
Kyoto University (京都大学) / 0048 / 新制・課程博士 / 博士(農学) / 甲第18312号 / 農博第2037号 / 新制||農||1020(附属図書館) / 学位論文||H26||N4819(農学部図書室) / 31170 / 京都大学大学院農学研究科地域環境科学専攻 / (主査)教授 天野 洋, 教授 田中 千尋, 教授 松浦 健二 / 学位規則第4条第1項該当
92

O espaço das calçadas em cidades não-metropolitanas: O caso de Carpina – Pernambuco

LOPES, Jaciara Da Conceição Andrade 14 March 2016 (has links)
Submitted by Irene Nascimento (irene.kessia@ufpe.br) on 2016-07-20T17:38:40Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) DISSERTAÇÃO FINAL - Jaciara Lopes - MDU UFPE 2016.pdf: 4397702 bytes, checksum: c5f17736093b5729caad495df535e022 (MD5) / Made available in DSpace on 2016-07-20T17:38:40Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) DISSERTAÇÃO FINAL - Jaciara Lopes - MDU UFPE 2016.pdf: 4397702 bytes, checksum: c5f17736093b5729caad495df535e022 (MD5) Previous issue date: 2016-03-14 / FACEPE / A pesquisa objetivou analisar as inter-relações e os conflitos existentes entre os usos e a gestão do espaço das calçadas, em cidades não-metropolitanas médias e pequenas, a partir das intervenções cotidianas dos indivíduos, adotando como estudo de caso, a área urbana do município de Carpina/Pernambuco, especificamente a Avenida Estácio Coimbra, localizada no Bairro São José e a Avenida Doutor Joaquim Nabuco, localizada no Bairro Centro. O interesse em investigar essa temática surgiu a partir da observação empírica da dinâmica do espaço das calçadas em cidades não-metropolitanas, nas peculiaridades, semelhanças e diferenças do espaço das calçadas das metrópoles, principalmente quanto aos usos, gestão, conflitos e inter-relações existentes nesse espaço. Sendo assim, questiona-se: Em que dimensões, os indivíduos influenciam nos usos, na gestão, nos conflitos e nas inter-relações no espaço das calçadas em cidades não-metropolitanas médias e pequenas? Há territórios no espaço das calçadas? E se há, como eles se dividem? Os procedimentos metodológicos elegidos para a execução deste trabalho consistiram: na pesquisa bibliográfica, onde foram considerados conteúdos referentes à formação e reestruturação do espaço urbano, dos espaços livres públicos e do espaço das calçadas; além da análise de leis, planos e normativas referentes ao uso e ocupação do solo no município; na observação empírica da dinâmica do espaço das calçadas na cidade; nas conversas informais com indivíduos citadinos, e; na aplicação de uma entrevista semiestruturada, realizada também, com os indivíduos citadinos, identificando inter-relações e possíveis elementos conflitantes nesse espaço. Através das informações recolhidas, almejou-se realizar um diagnóstico acerca dos usos e das funcionalidades encontradas no espaço das calçadas, analisando, por meio de um recorte físico/temporal, situações e/ou elementos conflitantes, bem como, a atuação dos usuários nesse espaço, apontando Carpina como um exemplo de cidade não-metropolitana, que pode apresentar características particulares em sua dinâmica urbana. Consolidando-se como uma temática pertinente, uma vez que busca compreender de que maneira as inter-relações e os conflitos, produzidos pelos agentes sociais, interferem nos usos e na gestão do espaço das calçadas nas cidades não-metropolitanas, a pesquisa busca contribuir para uma nova experiência urbana, reconhecendo que, embora existam leis contratuais fundamentando o desenvolvimento de um município, ao que Gomes (2002) define de nomoespaço, é possível encontrar uma realidade diferente, onde, as práticas socioespaciais, a força da amizade e os acordos de interesses, promovidos pelos citadinos, é quem define esse espaço, ao que o mesmo autor nomeia de genoespaço. Entretanto, ainda que alguns agentes sociais elejam diversos espaços nas calçadas, e, nesses espaços, firmem novos territórios, impondo sobre eles, novas regras de usos, de ocupação e de gestão, diferente dos códigos de conduta que regem o município, o espaço das calçadas necessita ser observado e apropriado, nas cidades não-metropolitanas médias e pequenas, como um espaço livre público, altamente democrático e sustentado por uma rica dinâmica urbana. / The research aimed to analyze the interrelations and conflicts among uses and space management of sidewalks, small and medium cities in non-metropolitan, through daily interventions of individuals, urban area of the municipality of Carpina/Pernambuco, specifically the Estacio Coimbra Avenue, located in Bairro São José and the Doutor Joaquim Nabuco Avenue, located in the Central District. The interest in investigating that topic it has emerged from the empirical observation of the space sidewalks in non-metropolitan cities, the peculiarities, commonalities and differences of space the sidewalks of cities, particularly as to the uses, management, conflicts and existing interrelations that space. Thus, the question is: In that dimension, the individuals influence in the use, management, conflict and on the interrelations space the sidewalks in cities small and medium non-metropolitan? Are there any territories within the sidewalks? And if there is, how did they divide? Methodological elected to perform this work consists of: in literature, in which they were considered contents related to the formation and restructuring of urban space, of public open spaces and space of the sidewalks; Apart from analysis of laws, plans and regulations concerning the use and occupation of land in the municipality; the empirical observation of dynamics of space sidewalks in the city; in informal conversations with townspeople individuals and; the application of a semi-structured interview, carried out also with the townspeople individuals, identifying inter-relationships and possible conflicting elements in that space. Through the collected information, aspired to make a diagnosis about the uses and functionality found within the sidewalks, analyzing, by means of a physical trimming / temporal positions and / or conflicting information, as well as the actions of users in that space, Carpina pointing as an example of non-metropolitan city, which may have particular characteristics in its urban dynamics. Consolidating its position as a relevant theme as it seeks to understand how the interrelations and conflicts, produced by social agents interfere in the use and management of space sidewalks in non-metropolitan cities, that research seeks to contribute to a new urban experience, recognizing that although there are contract law basing the development of a municipality, what Gomes (2002) defines nomoespaço, you can find a different reality, where the socio-spatial practices, the strength of friendship and the interests agreements, promoted by townspeople, is one who defines this space by the same author names of genoespaço. However even if some social workers may elect several spaces on the sidewalks, and in these spaces, get new territories, enforcing on them new rules of use, occupancy and management, different codes of conduct that govern the municipality, the space of sidewalks need to be observed and appropriate, in cities small and medium non-metropolitan, as a public space, highly democratic and supported by a rich urban dynamics.
93

Soubor výukových programů / The set of tutorial programs

Vaculík, Jakub Unknown Date (has links)
With increasing demands for transit capacity of data networks as well as communication network optical networks seem to be the suitable solution. Light beam is attractive to use for data transmission . Transmitted data can be expressed by means of light impuls.. For execution of the project we need the whole optical telecommunical system which consists of transmitter, transmission link and receiver. The target of transmission link is to transfer optical beam from its resourse to detector with minimal losses. The optical fibre or optical freespace optical link FSO are used for this purpose. This thesis discusses basic effects that accompany these roads. The program that is created in this study clearly shows and describes the dependence of these phenomena on the individual input parameters. It is designed for students so that they can better imagine how these phenomena take place.
94

Paving the Way for Next Generation Wireless Data Center Networks

AlGhadhban, Amer M. 05 1900 (has links)
Data Centers (DCs) have become an intrinsic element of emerging technologies such as big data, artificial intelligence, cloud services; all of which entails interconnected and sophisticated computing and storage resources. Recent studies of conventional data center networks (DCNs) revealed two key challenges: a biased distribution of inter-rack traffic and unidentified flow classes: delay sensitive mice flows (MFs) and throughput-hungry elephant flows (EFs). Unfortunately, existing DCN topologies support only uniform distribution of capacities, provide limited bandwidth flexibilities and lacks of efficient flow classification mechanism. Fortunately, wireless DCs can leverage wireless communication emerging technologies, such as multi-terabit free-space optic (FSO), to provide flexible and reconfigurable DCN topologies. It is worth noting that indoor FSO links are less vulnerable to outdoor FSO channel impairments. Consequently, indoor FSO links are more robust and can offer high bandwidths with long stability, which can further be enhanced with wavelength division multiplexing (WDM) methods. In this thesis, we alleviate the bandwidth inefficiency by FSO links that have the desired agility by allocating the transmission powers to adapt link capacity for dynamically changing traffic conditions, and to reduce the maintenance costs and overhead. While routing the two classes along the same path causes unpleasant consequences, the DC researchers proposed traffic management solutions to treat them separately. However, the solutions either suffer from packet reordering and high queuing delay, or lack of accurate visibility and estimation on end-to-end path status. Alternatively, we leverage WDM to design elastic network topologies (i.e., part of the wavelengths are assigned to route MFs and the remaining for EFs). Since bandwidth demands can be lower than available capacity of WDM channels, we use traffic grooming to aggregate multiple flows into a larger flow and to enhance the link utilization. On the other hand, to reap the benefits of the proposed WDM isolated topology, an accurate and fast EF detection mechanism is necessary. Accordingly, we propose a scheme that uses TCP communication behavior and collect indicative packets for its flow classification algorithm, it demonstrates perfect flow classification accuracy, and is in order of magnitudes faster than existing solutions with low communication and computation overhead.
95

[pt] O USO DE SISTEMA GEOGRÁFICO DE INFORMAÇÃO NA IDENTIFICAÇÃO DE ÁREAS APTAS PARA OCUPAÇÃO DE ACORDO COM CRITÉRIOS BIOFÍSICOS: UMA APLICAÇÃO NO BAIRRO DE VARGEM PEQUENA – RIO DE JANEIRO / [en] THE USE OF GEOGRAPHIC INFORMATION SYSTEM FOR IDENTIFYING SUITABLE AREAS FOR OCCUPATION IN ACCORDANCE WITH BIOPHYSICAL CRITERIA: AN APPLICATION IN VARGEM PEQUENA NEIGHBORHOOD - RIO DE JANEIRO

29 October 2021 (has links)
[pt] A falta de critérios ambientais na ocupação do território pode trazer danos de longo prazo aos cidadãos e ao patrimônio natural da cidade. O objetivo do trabalho é identificar áreas aptas para ocupação urbana, considerando os aspectos geotécnicos do suporte e aqueles ligados à manutenção dos processos naturais, como base para a gestão e o desenho da cidade. Com o apoio de um sistema geográfico de informação é feita a análise e avaliação dos atributos biofísicos de uma área em processo de expansão urbana, o bairro de Vargem Pequena, na zona oeste da cidade do Rio de Janeiro. No local, uma parte significativa do território é constituída de espaços livres de ocupação. A análise e a avaliação do suporte biofísico estão calcadas em uma proposta metodológica interdisciplinar que reconhece os espaços livres como sistema, com um papel protagonista dentro da estrutura urbana e potencial para ordenar a ocupação do território. O núcleo das informações acerca do suporte biofísico da área é a correlação pedológico-geotécnica feita sobre o levantamento de solos do município. O PEDOGEO contém, além dos dados pedológicos de cada classe de solo, informações gerais sobre as principais características do meio físico. Os elementos definidos para análise são: cobertura; solo; hidrologia; e relevo. As avaliações mostram que a utilização de informações biofísicas é pertinente na caracterização da realidade espacial urbana para os fins propostos, indicando, contudo, ainda pouca disponibilidade de dados, de fontes confiáveis e em escalas adequadas, para este tipo de análise. / [en] This thesis deals with the analysis of the biophysical characteristics of areas in urban expansion process with the support of a geographic information system. We highlight the importance of studying the physical reality of territories for urban development in line with environmental values and sustainability principles. The objective of this work was the development of a synthesis map that can determine‒through gradation values and within established criteria‒suitable areas for occupation that do not conflict with the continuity of the natural processes of the territories. To this end, we propose to analyze and evaluate the biophysical attributes of an area in the City of Rio de Janeiro. In this location, within the urban structure, there are spaces that can be characterized as free of occupation, whether in the form of urban infrastructure, roads or buildings. From available data, the use of geo-processing resources in the characterization of urban space reality will be assessed in order to elaborate a basis for management and design of the city. The growth dynamics of a city like Rio de Janeiro does not often comply with the most well-intentioned plans. When cities grow without any planning, it is very common to observe the occurrence of events that cause direct damage to the population, such as landslides and floods. In other occasions, the plans ignore the basic reality of the territory by not considering in depth the potential impact of their deployment. In both cases, the lack of consistent and accessible information on the physical characteristics of the territory results in failing to apply environmental criteria in the process of occupation. This makes the population vulnerable and can cause long-term damage to the environmental heritage of the city. Although environmental sustainability issues are related to almost any kind of human activity, it is in the cities where they occur in a more evident way. While these issues have grown in scale in recent decades and their solutions have become more and more urgent, the search for integration and balance between the natural and urban environments has definitely been incorporated to urban thinking. Information processing techniques that have emerged with the development of computational systems led to the development of tools such as the Geographic Information System and the Computer Aided Design, which represent a new milestone in the understanding of the physical world, which is necessary to deal with urban and environmental issues within the scale they are placed nowadays. Authors, who deal with the topic of environmental spatial analysis from several approaches, provide the basis of the theoretical foundation of this work. The urban approach regards concepts linked to ecological urbanism and, in this context, the role of the system of open spaces in the urban structure. Concepts relating to biophysical support are reviewed, in an approach to the elements found in the area of study, especially those related to analysis and evaluation. In the case of geographical information systems, we make a summary of their peculiarities, main functions and foundations, and their application in the analysis of the territory. The analysis and evaluation of biophysical support are based on an interdisciplinary methodological proposal of the System of Open Spaces and the Territorial Project. These recognize the free spaces as systems, with a protagonist role within the urban structure and potentialities for territory restructuring. At the same time, they consider the guidance of a future occupation which does not conflict with the maintenance of natural support processes. In the adaptation of the original methodology for the purposes of this thesis, we considered that some criteria and conditions used for the definition of the areas that must be kept free of occupation, within the concept of open spaces system, could also define, in counterpoint, the spaces with better potential for occupation. In this way, the best evaluated areas in this study, from their biophysical characteristics, would be those whose urban occupation would avoid damage to ecosystems, contributing to the maintenance or recovery of the open spaces system. The area of study is defined by the administrative boundaries of Vargem Pequena neighborhood, located in the west zone of the City of Rio de Janeiro, with a total area of 1,443.83 ha. The neighborhood occupies a stretch of the Baixada de Jacarépaguá plain and part of the southern slope of the Maciço da Pedra Branca, which is an important area of environmental protection. The area can be considered one of the city s growth boundaries, limited by natural and urban environments, threatened by a series of unmanageability in its occupation process. In Vargem Pequena, the occupation is characterized by farms and low density residential urbanization of middle and upper-middle classes, also with the occurrence of irregular settlements and slums. The bucolic surroundings and proximity of nature attracts real estate investments with a trend to slopes occupancy. The open spaces lose their original identity, becoming isolated spaces without an effective participation in urban conformation. They are environmentally protected, but threatened by the urban pressure and a rapid process of dismantling with higher occupation of the plain and slopes. The main source of specific data used in the analysis of biophysical support is the PEDOGEO of Vargem Pequena. It is a geo-referenced digital map containing the classification of soils within the administrative boundaries of the neighborhood. The basis of its contents is the soil survey of the City of Rio de Janeiro, which began in the 1960s, in the former State of Guanabara, and was revised and supplemented up to 2009. Another essential source of information is the work carried out by specialists, dealing with the relationship between pedology and geotechnics. The biophysical attributes analyzed were: vegetation; soil; relief; and hydrology. In the research, we used data available and already converted to the Geographic Information System environment, enabling their immediate application. In the organization of information plans, analysis and generation of maps, we used the ArcGIS Desktop 10, ESRI, application package. In the complementation of planimetric information, we used the AutoCAD 2012, Autodesk, application. The geo-processing followed the current methodology in this environment, consisting basically of two steps: construction of a geo-referenced database; and spatial analyses and evaluations for the objective set. Structure of the geo-referenced database a) Scale of final product: 1:2000 b) Projection: UTM (Universal Transverse Mercator) c) Datum: SAD 69 d) Resolution: 1 m e) Information plans: coverage, soil, declivity, water bodies Procedures adopted in the construction of the geo-referenced database: 1. Collection of data and materials 2. Data conversion 3. Classification of coverage from images interpretation techniques 4. Creation of the digital terrain model 5. Classification of hillsides and declivity layer generation Procedures adopted in the analyses and spatial assessments: 1. Definition of the variables values 2. Operation between matrices 3. Final classification Information plans were created with the cropping of the area defined by the boundaries of the neighborhood. The coverage map was done with image interpretation techniques applied to orthorectified aerial images taken in 2009. The map represents the neighborhood surface through the following layers: vegetation; exposed soil; rocks; and urbanized area. The vegetation is classified on the basis of the criteria for analysis of the elements that constitute the system of open spaces, as a mosaic of ecosystems of different scales, considering their internal relationships and those with the surroundings. The urbanized area is divided into built, paved and public spaces. In the soil map, there is information available in the PEDOGEO regarding the pedological and geotechnical characteristics of each type of soil, in addition to data on the physical environment in which they are inserted. The declivity map, generated from the digital elevation model, and the map of water bodies, derive from the digital cartography of the city. The map records: the quota of altitude of the terrain through isograms every 1 m; and the existing water courses through polylines. Areas situated above 100 m altitude, which are part of the SPECIAL ZONE 1 for the preservation of the city, and areas with declivity greater than 30 per cent, or situated at 30 m from the banks of rivers, which form part of Permanent Protection Areas, protected by federal laws, are classified as areas of legal constraint for occupation. After the variables of each information plan were mapped, they were rasterized and reclassified, assigning the same value for each variable. According to the biophysical criteria set and the help of experts who knew the phenomena and situations assessed, we assigned grades 1 to 10 to each variable, from the smallest to the largest suitability of each area for occupation. We assigned grade zero to not classified areas: due to the lack of information; constituting legal restriction areas; or because they had already been urbanized. The matrices were then combined algebraically, resulting in the evaluation map, whose chromatic gradient reflects the degree of suitability for occupation, according to the criteria defined. The map produced with geo-processing resources shows that the biophysical criteria used are relevant in the characterization of the urban space reality for the management and design of the city. The work scale and the classification process of coverage allowed tracing a considerably updated and accurate picture of the urbanized area and the free spaces existing in the neighborhood. However, the final map has some inconsistencies, in part due to the lack of more precise information. The methodology used is simple and could be improved in future works, for example, by applying a mathematical logic more suited to environmental complexity, as the Weighted Average or Fuzzy logic. At the same time, the field biophysical information would be supplemented with the help of experts. Although the theoretical framework of ecological urbanism and technical data surveys on the environment have progressed in the last few decades, the objective information available in this area is still restricted. At first, the immediate experience could lead to the conclusion that this lack occurs more sharply in countries with many problems to face in the direction of effective development. However, according to the point of view of current authors in the field of geo-processing, it is possible to observe that worldwide research on the environment is just starting. In countries with environmental heritage‒like for example in Brazil‒there is a great need for appropriate surveys and processing of information about natural environments. It is expected that this work will contribute, albeit to a limited extent, with the practice of environmental analysis as a preliminary step for planning and the elaboration of urban projects. At the same time, it will contribute to the use of the Geographic Information System, at the level of users, as a current tool for professionals in the field, as for example the Computer Aided Design, whose use has been consolidated for a long time.
96

Elliptical Vortex Beams Through Turbulent Atmosphere.

Narváez Castañeda, Emmanuel January 2020 (has links)
No description available.
97

Koherence laserového svazku v turbulentní atmosféře / Laser beam coherence in turbulent atmosphere

Polanský, David January 2011 (has links)
In the first part of the thesis discusses the function of the laser design and construction of its class. Here is an explanation of coherence and other properties of laser radiation. Listed below are the possibilities of energy distribution in the laser beam. Described in particular Gaussian beam. The paper explains the phenomena of bending and Young's experiment. The paper examines the influence of atmospheric environment in the transmission of electromagnetic waves, defined as light. Particular attention is devoted to atmospheric turbulence. In the second part are first discussed the possibility of measuring atmospheric turbulence and coherence of laser beam parameters. The following is designed to measure workplace coherence width and coherence length in a turbulent environment. At these workplaces were measured. The results of these measurements are also listed in the job. The following comparison of results with theoretical values.
98

Měření komplexní permitivity materiálů metodou ve volném prostoru / Free space method for measurement of complex permittivity

Nekovář, Jiří January 2012 (has links)
The aim of this thesis is the development of the workplace for the complex permittivity measurement by free space method. At the beginning of this thesis, the method is described. Further attention is focused on the discussions concerning electromagnetic properties of materials, comparison of the methods used for complex permittivity measurement, interactions of planar electromagnetic wave with planar infinite dielectric slab of general environment and description of radiation patterns of microwave antennas. In the rest of the thesis, the measuring workplace for the free space method is designed and fabricated. A pyramidal horn antenna is selected as a radiator. The antenna is designed with coax to waveguide transition in CST Microwave Studio, and than fabricated in two samples and measured. Finally, the fabricated measuring workplace is exploited for the complex permittivity measurement.
99

MEMS-based Free Space Optical Networks

Atakora, Michael O. 23 May 2022 (has links)
No description available.
100

Comparative Analysis of Atmospheric Turbulence-induced Laser Power Fluctuations in a Monolithic and Tiled Optical Receiver System

Valero, Marcos E. 17 May 2021 (has links)
No description available.

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