Made available in DSpace on 2018-08-02T00:03:44Z (GMT). No. of bitstreams: 1 tese_10271_representation_of_multi_level_domains_on_the_web_2016 - freddy.pdf: 1850597 bytes, checksum: 49e1ac6068e9ec186891d6c01f4acab9 (MD5) Previous issue date: 2016-09-28 / Estratégias de modelagem conceitual e representação de conhecimento frequentemente tratam entidades em dois níveis: um nível de classes e um nível de indivíduos que instanciam essas classes. Em vários domínios, porém, as próprias classes podem estar sujeitas a categorização, resultando em classes de classes (ou metaclasses). Ao representar estes domínios, é preciso capturar não apenas as entidades de diferentes níveis de classificação, mas também as suas relações (possivelmente complexas). No domínio de taxonomias biológicas, por exemplo, um dado organismo (por exemplo, o leão Cecil morto em 2015 no Parque Nacional Hwange no Zimbábue) é classificado em diversos táxons (como, por exemplo, Animal, Mamífero, Carnívoro, Leão), e cada um desses táxons é classificado por um ranking taxonômico (por exemplo, Reino, Classe, Ordem, Espécie). Assim, para representar o conhecimento referente a esse domínio, é necessário representar entidades em níveis diferentes de classificação. Por exemplo, Cecil é uma instância de Leão, que é uma instância de Espécie. Espécie, por sua vez, é uma instância de Ranking Taxonômico. Além disso, quando representamos esses domínios, é preciso capturar não somente as entidades diferentes níveis de classificação, mas também suas (possivelmente complicadas) relações. Por exemplo, nós gostaríamos de afirmar que instâncias do gênero Panthera também devem ser instâncias de exatamente uma instância de Espécie (por exemplo, Leão). A necessidade de suporte à representação de domínios que lidam com múltiplos níveis de classificação deu origem a uma área de investigação chamada modelagem multi-nível. Observa-se que a representação de modelos com múltiplos níveis é um desafio em linguagens atuais da Web Semântica, como há pouco apoio para orientar o modelador na produção correta de ontologias multi-nível, especialmente por causa das nuanças de restrições que se aplicam a entidades de diferentes níveis de classificação e suas relações. A fim de lidar com esses desafios de representação, definimos um vocabulário que pode ser usado como base para a definição de ontologias multi-nível em OWL, juntamente com restrições de integridade e regras de derivação. É oferecida uma ferramenta que recebe como entrada um modelo de domínio, verifica conformidade com as restrições de integridade propostas e produz como saída um modelo enriquecido com informações derivadas. Neste processo, é empregada uma teoria axiomática chamada MLT (uma Teoria de Modelagem Multi-Nível). O conteúdo da plataforma Wikidata foi utilizado para demonstrar que o vocabulário poderia evitar inconsistências na representação multi-nível em um cenário real.

The loss of habitat to agriculture is a worldwide problem for biodiversity conservation. One species that has seemingly been able to adapt to the conversion of forests to farmlands is Mackinder’s eagle owl (Bubo capensis mackinderi), which inhabits highland areas, but little is known of its ecology, especially outside of protected areas. This study examined the impact of agricultural practices and farmer’s attitudes on the foraging and population ecology of the Mackinder’s eagle owl in central Kenya. Owl territories were monitored monthly from June 2004- October 2006 for signs of occupancy, breeding activity, mortality and to collect data on food resources. Nest site characteristics were measured for all known nests. Because previous studies showed an affinity for rodents, small mammals were trapped monthly using mark-recapture methodology. In each territory, the type and amount of farm crops were measured each month and farmers were interviewed about their knowledge and beliefs about owls. Mackinder’s eagle owls in central Kenya lived at extremely high density 0.87 owl pairs/km². This density was high compared to other populations of Mackinder’s eagle owl and to Eurasian eagle owl (Bubo bubo) populations in Europe. Breeding success was 48% over three years and this compared well with other species of eagle owl inhabiting human-disturbed areas. All nests and roosts were located in river valleys, and all successful nest sites were located on cliffs or other inaccessible rocky terrain. Nest sites were located adjacent to farms, which provided for both open hunting and an abundance of prey. Breeding activity was concentrated after the rainy seasons and this was likely linked to prey availability after the rains. Agricultural activities generally had a positive effect on rodent populations. Small mammal trapping results revealed that rodents were over 14 times more abundant in farms than in adjacent grassland habitat. This population of Mackinder’s eagle owl had a very catholic diet and consumed mostly mammalian prey species including hares, giant rats, root rats, grooved-tooth rats and small rodents. Small rodents accounted for almost half of the owls’ diet and when their numbers increased, owls responded by consuming more of them, indicating the importance of farming activities to this population of owls. Other populations of eagle owl inhabiting human-disturbed areas had diet widths positively related to levels of habitat disturbance. This result supported optimal foraging theory that more productive environments have predators with more specialized diets, while patchy environments have generalist predators. The ecology of this population of Mackinder’s eagle owls was heavily influenced by human agricultural activities, which generally had a positive effect on their population. Farming activities changed rapidly both within and between seasons as plots were small and neighbouring farmers planted various crops at different times of the year and this was enhanced by irrigation in some areas. Year-round availability of forage within farms had a positive effect on owl prey species, some of which increased relative to the type and amount of crops found in farms. However, 57% of owl injuries and mortalities that occurred were related either directly or indirectly to human activities. Cultural prejudices against owls remain the biggest threat to this population’s long-term persistence. Farmer education was shown to play a significant role in overcoming negative beliefs about owls. Because Mackinder’s eagle owls are highly adaptable to anthropomorphic landscape changes, largely due to their adaptability as food generalists, they are one of the few top predators remaining in this highly disturbed agricultural system. However, populations within agricultural areas remain especially vulnerable to negative human attitudes towards owls due to their close association with human activities.

In the computationally intensive and diverse scientific environment of geosciences, substantial volumes of data are generated by specialized complex processing systems called ‘models’. These datasets contain little knowledge of their processing. Therefore a high degree of domain expertise is required to interpret, regenerate and tweak their production. Provenance is described as a general ability to record and evolve information related to the creation of data. We extend this idea further by proposing a mechanism by which a model’s setup and its domain semantics are integrated with the data it produces. This creates a scope for controlling model executions using their respective setups or ‘configurations’. In this work we created an application neutral framework which can be applied to models of a similar class in geosciences. Our objective is to allow scientists to share their experiments with anyone having an interest in it while allowing for formally controlled and extensible customizations.

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Ontologijos tampa vis populiaresnės, nes leidžia organizacijoms lanksčiau aprašyti dalykinę sritį, ieškoti informacijos iš skirtingų šaltinių ir pateikti semantiškai tiksliau atrinktus rezultatus vartotojams. Tačiau, augant informacijos ontologijoje kiekiui, saugoti ją tekstiniame faile tampa neefektyvu. Šio tyrimo tikslas yra pagerinti užklausų vykdymo ontologijoje galimybes, kai jos saugojamos reliacinėje duomenų bazėje. Tam buvo sukurtas SPARQL užklausų vykdymo metodas ontologijoje, saugojamoje reliacinėje duomenų bazėje pagal OWL2RDB algoritmą. Eksperimentas patvirtino, kad esant dideliam individų skaičiui, metodas leidžia greičiau vykdyti užklausas reliacinėje duomenų bazėje saugojamoje ontologijoje, negu ontologijoje, saugojamoje tekstiniame faile. / Ontologies are becoming increasingly popular because they allow organizations to describe their problem domains in a more flexible manner and to search information from multiple sources giving semantically significant results for users. However, the increasing amount of information in ontology makes its storing in a text file not effective. The aim of this research is to improve possibilities of querying large ontologies when these are kept in relational databases. The method was created for executing SPARQL queries in ontology, stored in a relational database created by OWL2RDB algorithm. Experiments have shown that the method improves query performance time in comparison with existing query engine especially for large ontologies having many individuals.

<p>Tri osnovna cilja su predmet istraživanja u doktorskoj disertaciji. Prvi cilj je da se prouče mogućnosti modelovanja poslovnih informacionih sistema kori&scaron;ćenjem ontolo&scaron;kog pristupa modelovanju informacionih sistema. Drugi cilj je da se razvije model informacionog sistema državnih garancijskih fondova baziran na primeni objektnog i ontolo&scaron;kog pristupa modelovanju. Treći cilj je da se implementira prototip informacionog sistema državnih kreditno-garancijskih fondova i da se verifikuje na slučaju Grancijskog fonda APV. Metodologija: Za modelovanje sistema je kori&scaron;ćen ontolo&scaron;ki pristup primenom metodologije METHONTOLOGY, kao i alati za modeliranje i analizu ontologija (Protege). Za implementaciju prototipa je kori&scaron;ćena Microsoft .NET platforma. Rezultati istraživanja su verifikovani i testirani sa podacima iz poslovnih aktivnosti Garancijskog fonda APV.<br />Rezultati. U ovoj disertaciji su ostvareni sledeći rezultati: Na osnovu istraţivanja iz oblasti modelovanja informacionih sistema primenom ontolo&scaron;kog pristupa i identifikovanih modela funkcionisanja državnih garancijskih fondova, kreiran je konceptualni model drţavnih garancijskih fondova koji je poslužio kao osnova za razvoj ontolo&scaron;kog modela Garancijskog fonda APV. Ontolo&scaron;ki model OMGFAPV je kreiran upotrebom Methontology metodologije. OMGFAPV semantički opisuje poziciju i hijerarhiju Garancijskog fonda APV u okvirupokrajinske administracije kao i sadržaje koji su iskori&scaron;ćeni dalji za razvoj dela informacionog sistema Garancijskog fonda APV. U okviru ovih istraţivanja ostvarena su dva naučna doprinosa. Prvi doprinos je predlog metodologije transformacije semantičkih sadrţaja koji su opisani u ontolo&scaron;kom modelu u korisnički interfejs (KI) koji je standardna komponenta informacionog sistema. Drugi doprinos odnosi se na upotrebu ontolo&scaron;kih modela za modelovanje i implementaciju poslovne logike. Ova istraţivanja su obuhvatila specifičnosti podr&scaron;ke odlučivanju u procesu izdavanja garancija u državnim garancijskim fondovima. Rezultat istraţivanja je SCORE ontologija koja predstavlja zasebnu komponentu informacionog sistema Garancijskog fonda APV. Ograničenja istraživanja / implikacije: Ograničenjapredloţenog modela OMGFAPV odnose se na potrebu njegovog pro&scaron;irivanja usled specifičnih potreba, odnosno kompleksnijih operativnih procedura u procesu izdavanja garancija.Predložena metodologija transformacije semantičkih sadržaja u ontolo&scaron;kom modelu u korisnički interfejs ograničena je na kreiranje komponenti korisničkog interfejsa za unos ulaznih podataka poslovnih procedura. Osnovno ograničenjepredložene SCORE ontologije je njena stroga specijalizovanost. Predložena ontologija implementira socijalne i ekonomske karakteristike koje su od značaja za razvoj konkretnog regiona i jedan konkretan model evaluacije izdavanja garancija baziran na indeksima prioriteta. Ontologija ne sadrži generalizacije koje bi omogućile njeno direktno kori&scaron;ćenje za druge regione ili druge modele evaluacije predloga odluke i izdavanju garancija. Praktične implikacije:<br />Kreirani model informacionog sistema obezbeđuje kreiranje i praćenje podataka i dokumenata u svim fazama procesa izdavanja garancije. Pri tome je poseban naglasak na proceni kreditne sposobnosti aplikanata i distribuciji i razmeni podataka sasvimučesnicima učesnici u procesu izdavanja garancija. Sistem obezbeđuje minimalno sintaktička i koliko je moguće semantičku interoperabilnost sa eksternim učesnicima u procesu (druge finansijske institucije, organi uprave) kao i jednostavno kori&scaron;ćenje onim korisnicima (pre svega aplikanti, ali i administrativni sluţbenici) koji ne poseduju specifična stručna znanja iz oblasti rada garancijskog fonda. Originalnost/vrednost: Ontolo&scaron;kim pristupom modeliranju sistema a posebno kreiranjem ontologija kojima je predstavljeno znanje o administrativnim procesima stvaraju se pretpostavke za tehničku i organizacionu interoperabilnost različitih drţavnih organa. Pri tome, izuzetno vaţan aspekt je fleksibilan i ekonomičan mehanizam za kreiranje korisničkog interfejsa koji obezbeđuje interakciju različitih tipova korisnika (zaposleni u administraciji, zaposleni u privrednim subjektima i građanstvo) sa sistemom eUprave. Predlog modela ontolo&scaron;ki baziranog generisanja korisničkog interfejsa koji je opisan u disertaciji predstavlja ideju da se standardizuje reprezentacija korisničkog interfejsa. Generisanje i dizajn korisničkog interfejsa su svedeni na razvoj formalizovane ontologije administrativnog procesa koja uključuje opis interakcije korisnika sa sistemom putem anotacija operativnih procedura. Ontologija u kojoj su semantički predstavljene socijalne i ekonomske karakteristike koje obuhvata oblast delovanja državnih razvojnih fondova i koje su od značaja za razvoj analiziranog regiona obezbeđuje proces odlučivanja koji omogućuje dono&scaron;enje odluka o plasmanu državnih sredstava u skladu sa državnim strategijama razvoja.</p> / <p>The research in this doctoral dissertation has three main objectives. The first objective is to study the possibilities of modelling information systems by using an ontological approach. The second objective is to develop a model of information system of state guarantee funds based on the object oriented and the ontological approach to the modelling. The third goal is to implement a prototype of an information system of the state credit-guarantee funds and to verify the case of the Guarantee fund of APV. Methodology: Ontological approach is used for building a model. Methodology METHONTOLOGY was used to build the ontology, as well as tools for modelling and analysis of ontology (Protege). Microsoft .NET platform was used for the implementation of the prototype. The research results are verified and tested with data from operating activities of the Guarantee Fund APV.<br />Results. In this dissertation, the following results were achieved: Based on the research in the field of modelling of information systems using the ontological approach and identified models of the state guarantee funds, the author created a conceptual model of state guarantee funds, which served as the basis for the development of the ontological model of the Guarantee Fund APV. The ontological model OMGFAPV was created using Methontology methodology. OMGFAPV semantically describes the position and hierarchy of the Guarantee Fund of APV within the provincial administration and the contents of which are used for the further development of part of an information system for the Guarantee Fund of APV. Two scientific contributions were realized within these studies. The first contribution is the proposed methodology of transformation of the semantic contents that are described in the ontological model in the user interface component of the information system. The second contribution is the use of ontological models for modelling and implementing business logic. These studies included the specifics of the decision support in the process<br />KEYWORD DOCUMENTATION<br />252<br />of issuing guarantees in the state guaranty funds. The result of this research is a SCORE ontology that represents a separate component of the information system of the Guarantee Fund APV. Research Limitations / Implications: The limitations of the proposed model OMGFAPV refer to the need of expanding due to its specific needs, or more complex operating procedures in the process of issuing the guarantees. The proposed methodology for transformation of semantic content of the ontological model in the user interface is limited to the creation of components of the user interface for entering input data of the business procedures. The key limitation of the proposed SCORE ontology is its strict specialization. The proposed ontology implements social and economic characteristics that are important for the development of a region. The ontology does not contain generalizations that would allow its direct use in other regions or other models of decision proposal in the process of issuing guarantees. Practical implications: The created model of information systems provides the design and monitoring of data and documents in all stages of the process of issuing the guarantee. It is a special emphasis on assessing creditworthiness of applicants and the distribution and exchange of information with all stakeholders, participants in the process of issuing the guarantee. The system provides minimal syntactic and semantic interoperability with external stakeholders (other financial institutions, administrative authorities) as well as ease of use to the users (primarily applicants, and administrative officials) who do not possess specific expertise in the field of labor guarantee fund . Originality / value:<br />The ontological approach to modelling systems, particularly by creating an ontology which is represented by knowledge of administrative processes creates the prerequisites for technical and organizational interoperability of the various government bodies. In addition, an extremely important aspect is a flexible and cost-effective mechanism for creating a user interface that provides interaction of different types of users (employees of the administration, employees of companies and citizens) with a system of eGovernment. The proposal of the ontological model-based generation of user interface that is described in this dissertation presents the idea to standardize the representation of the user interface. Generating and designing of the user interface is reduced to the development of formalized ontology of the administrative process, which includes a description of user interaction with the system via operating procedures annotations. The ontology in which social and economic characteristics are semantically represented, which covers the area of operation of state development funds and which is of importance for the development of the analyzed region provides the decision-making process for making decisions about the placement of state funds in accordance with national development strategies.</p>

[pt] O termo dados interligados refere-se a conjuntos de triplas RDF organizados segundo certos princípios que facilitam a publicação e o acesso a dados por meio da infraestrutura da Web. Os princípios para organização de dados interligados são de grande importância pois oferecem uma forma de minimizar o problema de interoperabilidade entre bancos de dados expostos na Web. Este trabalho propõe enriquecer um banco de dados que contém descrições em RDF de cubos de dados, interligando seus componentes com entidades definidas em fontes de dados externas através de triplas owl:sameAs. O trabalho propõe uma arquitetura composta por dois componentes principais, o enriquecedor automático e o enriquecedor manual. O primeiro componente gera triplas owl:sameAs automaticamente enquanto que o segundo componente permite ao usuário definir manualmente as ligações. Em conjunto, estes componentes facilitam a definição de cubos de dados de acordo com os princípios de dados interligados / [en] The term Linked Data refers to a set of RDF triples organized according to certain principles that facilitate the publishing and consumption of data using the Web infrastructure. The importance of the Linked Data principles stems from the fact that they offer a way to minimize the interoperability problem between databases exposed on the Web. This dissertation proposes to enrich a database that contains Linked Data cube descriptions by interconnecting the components of the data cubes with entities defined in external data sources, using owl:sameAs triples. The dissertation proposes an architecture consisting of two major components, the automatic enriching component and the manual enriching component. The first component automatically generates owl:sameAs triples, while the second component helps the user manually define owl:sameAs triples that the automatic component was not able to uncover. Together, these components therefore facilitate the definition of data cubes according to the Linked Data principles.

Informação sobre o estágio de câncer num paciente é fundamental quando médicos avaliam o progresso de seu tratamento. A determinação do estágio de câncer (cancer staging) é um processo que leva em consideração a descrição, localização, características e possíveis metástases dos tumores cancerosos de um paciente. Esse processo deve seguir um padrão de classificação como, por exemplo, o padrão TNM. Porém, na prática clínica, a execução desse processo pode ser tediosa, propensa a erros e gerar incertezas. Com o intuito de amenizar esses problemas, este trabalho tem como objetivo auxiliar radiologistas fornecendo uma segunda opinião na avaliação do estágio de câncer de um paciente. Para isso, tecnologias da Web Semântica, como ontologias e reasoning, foram usadas para classificar automaticamente estágios de câncer. Essa classificação usou anotações semânticas feitas por radiologistas, usando a ferramenta ePAD, e armazenadas no formato AIM. Um protótipo de classificador, baseado no padrão TNM, foi criado. Ele transforma anotações AIM em indivíduos da ontologia AIM4-O e, usando axiomas e regras (escritos na linguagens OWL-SWRL) representando o padrão TNM, ele automaticamente calcula o estágio de câncer de fígado de pacientes. A ontologia AIM4-O foi desenvolvida, como parte desse trabalho, para representar anotações AIM 4 em OWL. Esse classificador TNM foi avaliado, usando-se dados reais de relatórios radiológicos de pacientes do NCIs Genomic Data Commons (GDC), em termos de precisão e revocação, com resultados respectivos de 85,7% e 81,0% (quando comparado aos valores reais de estágio de câncer dos relatórios). Todo o processo foi validado com radiologistas do Radiology Dept. of the Stanford University. / Information about cancer staging in a patient is crucial when clinicians assess treatment progress. Determining cancer stage is a process that takes into account the description, location, characteristics and possible metastasis of cancerous tumors in a patient. It should follow classification standards, such as the TNM Classification of Malignant Tumors. However, in clinical practice, the implementation of this process can be tedious, error-prone and create uncertainty. In order to alleviate these problems, we intend to assist radiologists by providing a second opinion in the evaluation of cancer stage in patients. For doing this, Semantic Web technologies, such as ontologies and reasoning, were used to automatically classify cancer stages. This classification used semantic annotations made by radiologists, using the ePAD tool, and stored using standard AIM format. A TNM based classifier prototype was created. It transforms AIM annotations in AIM4- O ontology individuals and, using axioms and rules (written in OWL-SWRL languages) representing the TNM standard, it automatically calculates patients liver cancer stage. The AIM4-O ontology was developed, as part of this work, to represent AIM 4 annotations in OWL. This TNM classifier was evaluated, using real patients radiology reports, from the NCIs Genomic Data Commons (GDC), in term of precision and recall, with 85.7% and 81.0% respective results (when compared to the actual cancer stages from the reports). The whole process was validated with radiologists from the Radiology Dept. of the Stanford University.

O cerrado é a maior, mais rica e provavelmente a mais ameaçada savana tropical do mundo. No entanto, grande parte de sua área foi ocupada por empreendimentos de agropecuária, nos quais não foram respeitados princípios básicos de conservação, sendo que cada grupo ou táxon reage de forma diferente a mudanças ambientais desse tipo. As aves de rapina, como os Falconiformes e os Strigiformes, são especialmente prejudicadas, pois são considerados predadores de topo de muitas teias alimentares. Porém, para saber como essas aves são afetadas pelas mudanças ambientais causadas pela ação do homem é necessário entender quais fatores são relevantes na \"escolha\" do ambiente de determinada espécie e assim compreender a razão de uma possível seletividade de hábitat. Sendo assim, o presente estudo observou características ecológicas de duas espécies de corujas comuns e bem distribuídas no Brasil, Megascops choliba e Athene cunicularia. Dentre os objetivos estão analisar a metodologia de estudo dessas aves de rapina, com possíveis efeitos na detecção de contatos e verificar o uso de hábitat, em diferentes fisionomias de cerrado, por parte das duas espécies de corujas. O estudo foi realizado na região da Estação Ecológica de Itirapina, no interior do estado de São Paulo. Para contatar as corujas foram realizados experimentos de playback em pontos de amostragem distribuídos em quatro fisionomias (neste estudo consideradas habitats) de cerrado. A atividade vocal de M. choliba variou conforme a temperatura e a umidade relativa. Esta espécie respondeu mais ao playback em condições de temperatura e umidade relativa altas. Athene cunicularia mostrou variar sua atividade vocal conforme a fase da lua e a intensidade do vento. Indivíduos desta espécie respondem mais intensamente ao playback em noites de lua cheia e menos em noites com ventos mais fortes. As duas espécies de corujas se distribuem diferentemente entre as fisionomias de cerrado. Athene cunicularia distribui-se distintamente entre fisionomias fechadas e abertas (Hk-w = 9,976; p = 0,0188), utilizando mais frequentemente as os campos limpo e sujo. Megascops choliba também se distribui diferentemente entre as fisionomias de cerrado (Hk-w = 10,88; p = 2 0,0137), utilizando preferencialmente o campo cerrado e o cerrado s.s.. Segundo os modelos tidos como os melhores, pela seleção de modelos feita através do AIC (Aikaike\'s Information Criterion), a variável com maior poder explicativo é o número de arbóreas para as duas espécies. Megascops choliba e A. cunicularia se segregam ecologicamente, havendo partição divergente de recursos espaciais, devido a seus requisitos para nidificação e forrageamento. Ocorre sobreposição intermediária no uso do habitat entre ambas espécies (O = 0,466). Já quanto a amplitude de nicho espacial (uso de habitat) M. choliba foi generalista (Bst = 0,753) e A. cunicularia intermediária (Bst = 0,453). Sendo assim, estas espécies divergem na seleção de habitat, se distribuindo diferentemente entre as fisionomias de cerrado de acordo com o número de arbóreas. Este estudo sugere, ainda, a importância de se levar em consideração as variáveis climáticas em estudos com o uso de vocalizações de aves de rapina noturnas, servindo também de subsídio para pesquisas futuras sobre censo dessas aves. / The Cerrado biome is the largest, richest and perhaps the most threatened tropical savannah of the world. However, most part of its natural areas has been transformed on agrosystems and pastures where basic principles of conservation weren\'t respected. Each biological group or taxa are affected on different ways by this change. Birds of prey are particularly affected because of its position in trophic webs, as they are top predators. To understand how these birds are affected by change caused by human land use, it is necessary to understand which factors are important for habitat selection, and then understand the species-habitat relationship. Thus, we observed ecological aspects of two widespread and common owls on Brazil: Tropical Screech-Owls (Megascops choliba) and Burrowing Owl (Athene cunicularia). The main objectives of this study included an analysis of methodological aspects of studying these owls species through playback and observe their habitat use. The study was conducted in the Estação Ecológica de Itirapina, State of São Paulo, Brazil. For doing it, we used playback experiments to detect these owls on four different cerrado physiognomies Vocal activities of Tropical Screech-owls were more detected in conditions of higher temperature and humidity. On the other hand, the Athene cunicularia answered more to playback in lower wind speed conditions and/or at full moon nights. The Burrowing Owl explored more frequently open physiognomies of cerrado, as campo limpo and campo sujo (Hk-w = 9.976; p = 0.0188). Conversely, Megascops choliba is more often found on campo cerrado, avoiding campo limpo (Hk-w = 10.88; p = 0.0137). According to Aikaike\'s Information Criterion (AIC) selection model, the most important variable to explain the distribution of both species in cerrado is the number of trees. There was ecological segregation between Megascops choliba and A. cunicularia. The spatial niche was intermediarily segregated (Pianka´s niche overlap measure O = 0.466), according their different needs for nesting and foraging. Additionally, these owls displayed broader (M. choliba Bst = 0.753) or intermediate (A. cunicularia Bst = 0.453) spatial niche breadths. On this sense, these owls have different needs on habitat selection, and their different distributions in cerrado were related more intrinsically to the number of trees present on each physiognomy, which is related to their nesting and foraging requirements. Aditionally, this study suggests, the importance to consider the influence of weather conditions on broadcast survey techniques for nocturnal raptors, which may be considered in further studies on census of these birds.