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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.
691

Herbage production as a function of soil moisture stress in a semiarid area

Owtadolajam, Esmail. January 1982 (has links)
Soil water deficits greatly affect forage production. To evaluate the effects of soil moisture stress on forage production, a budgeting model was developed. The soil water budgeting model uses the initial soil water content which can be assumed or calculated. Stress was calculated as a difference between potential evapotranspiration and actual evapotranspiration at a level of - 5 bar. A radiation method was used to calculate the potential evapotranspiration and the soil water budgeting model was used to calculate the actual evapotranspiration. The Soil Conservation Service method was applied to calculate runoff and effective rainfall was calculated by subtraction of runoff from original rainfall and used in the model for calculation of actual evapotranspiration. Calculated stress was correlated to the yield and stepwise multiple regression were used to produce prediction equations. Observed soil water data and yield for calibration and validation of the models were obtained from Santa Rita Forest and Range Experimental Range in southeastern Arizona.
692

The structure of the rutile TiOâ‚‚(110) surface and Ni/TiOâ‚‚ nanoislands

Tanner, Robert E. January 1999 (has links)
No description available.
693

Utilization of Corridor Habitat by White-tailed Deer (Odocoileus virginianus) in Denton County, Texas

Bruce, Troy Kenneth 05 1900 (has links)
White-tailed deer (Odocoileus virginianus) (N=15) movements were determined with use of radio telemetry techniques to determine the utilization of corridor habitat on the Lake Ray Roberts Greenbelt Corridor (RRGC) in north central Texas. Home ranges were calculated using three estimation types. Male white-tailed deer tend to have home ranges twice that of female home ranges. Seasonal home ranges were largest during spring (Feb. - April) and fall (Aug. - Oct.) seasons. Males had greater seasonal variation in utilization than females. No statistically significant difference (p=0.24) between white-tailed deer locations when the RRGC experiences heavy human traffic compared to days when there is light human traffic. Linearity indices indicated home ranges less linear than expected (LI = 3.02). The RRGC should be maintained at its current status to provide a variety of vegetational types and protective cover for white-tailed deer and other wildlife of Denton County.
694

The Relationship Between Scores on the Wechsler Intelligence Scale for Children-Revised and Scores on the Wide Range Achievement Test

Harris, Joneel J. 05 1900 (has links)
The problem with which this study is concerned is establishing the relationship between scores on the Wechsler Intelligence Scale for Children-Revised (WISC-R) and the Wide Range Achievement Test (WRAT). The findings indicated a highly significant positive relationship between the WISC-R and WRAT, yielding a a < .001 for all rs between WISC-R Verbal, Performance, and Full Scale IQs and WRAT Reading, Spelling, and-Arithmetic. Analysis of WISC-R and WRAT subtests revealed slightly less significant relationships (a of at least .01) for all possible combinations. Results of this study indicate the possibility of using the WRAT Arithmetic score as a quick estimate of general level of achievement.
695

Elektriskt Framdrivningssystem för Högpresterande Ultralätt Flygplan / Electric Propulsion for High Performance Ultralight Aircraft

Edlund, Per, Mami, Nihel January 2017 (has links)
Företaget BlackWing Sweden AB tillverkar ultralätta flygplan av kolfiberkomposit. Företaget vision är att tillverka ett flygplan som helt kan drivas av elektricitet med samma prestanda som flygplan drivet av fossila bränslen. För att kunna driva BlackWing flygplanet med hjälp av elektricitet behövs ett batteripaket, elektronikstyrning samt en elmotor. Därför har detta examensarbete ägnats åt att främst undersöka vilka elmotorer och battericeller som är mest lämpade för BlackWing flygplanet. Därefter togs resultatet fram genom beräkningar på battericeller och motorpaket med hjälp av insamlad information om motor-och batteriprestanda. För att få ett mer objektivt och systematiskt resultat här även en Pugh-matris används för att på ett enkelt sätt avgöra den mest lämpliga battericellen. Resultatet av detta arbete visade sig att i dagsläget är batteriet Envia, High Energi Pouch cell (ENV35011-CRC) och Siemens motor DYNADYN® 85 är mest lämpliga för BlackWing flygplanet. / BlackWing Sweden AB manufactures ultralight aircraft made from carbon fibre composite. The company's vision is to produce an aircraft that can be completely powered by electricity with the same performance as the aircraft powered by fossil fuels. To operate the BlackWing aircraft using electricity it will need a battery pack, electronic controls and an electric driveline. Therefore, this thesis has been devoted primarily to study which electric engine and battery cells that would be most suitable for the BlackWing aircraft. The result was produced by calculations of the battery cells and electric driveline by using collected information about driveline and battery performance. To get a more objective and systematic results, a Pugh matrix was used to easily determine the most suitable battery cell. The results of this work showed that in the current situation, the battery Envia High Energy Drone Cell Pouch (ENV35011-CRC) and Siemens engine DYNADYN® 85 are the most suitable for the BlackWing aircraft.
696

Representing attacks in a cyber range / Representation av attacker i en cyber range

Hätty, Niklas January 2019 (has links)
Trained security experts can be a mitigating factor to sophisticated cyberattacks that aim to violate the confidentiality, integrity, and availability of information. Reproducible sessions in a safe training environment is an effective way of increasing the excellence of security experts. One approach to achieving this is by using cyber ranges, which essentially is a set of hardware nodes that can virtually represent a large organization or system. The Swedish Defense Research Agency (FOI) develops and maintains a fully functioning cyber range and has the ability to automatically deploy sophisticated attacks against organizations and systems represented in this cyber range through a system called SVED. In this thesis, the capability to deploy different types of cyberattacks through SVED against virtual organizations in a cyber range, CRATE, is investigated. This is done by building a dataset of publicly disclosed security incidents from a database and attempting to represent each of them in SVED, and subsequently instantiating these attack representations against organizations in CRATE. The results show that the prevalence of at least one CVE-entry (Common Vulnerabilities and Exposures) in the incident description is a key factor to be able to represent an attack in SVED. When such an entry does exist, SVED is likely able to implement a representation of the attack. However, for certain type of attacks a CVE-entry is not enough to determine how an attack was carried out, which is why some attacks are harder to implement in SVED. This was the case for Denial of Service (DoS) attacks, which are too reliant on infrastructure rather than one or more vulnerabilities, and SQL injections, which are more reliant on the implementation of database access. Finally, CRATE is able to handle almost all attacks implemented in SVED, given that the correct vulnerable application software is installed on at least one machine in one of the organizations in CRATE.
697

Long-range electrodynamic interactions among biomolecules / Interactions électrodynamiques longues distances entre biomolécules

Lechelon, Mathias 11 December 2017 (has links)
L’étude des organismes vivants, la biologie, s’étend sur de nombreux domaines et notamment s’applique à comprendre le fonctionnement des êtres vivants. Les organismes les plus complexes comme les êtres Humains possèdent plusieurs niveaux d’organisation : ils sont constitués successivement d’organes, de tissus, de cellules, de biomolécules. On trouve plusieurs types de biomolécules dont les protéines, qui sont comme des minuscules outils qui permettent aux cellules de vivre et d’interagir avec leur environnement. Pour cela, les protéines doivent entrer en contact les unes avec les autres de manière très précise et déterminée. Cette thèse teste l’existence de forces électrodynamiques de longue portée qui leur permettraient d’interagir de manière rapide et guidée, via l’étude de l’absorption ou l’émission de ce type d’onde par des protéines, puis la diffusion de ces protéines en solution pour observer leur comportement. / The study of living organisms, biology, extends over many fields and in particular, applies to understanding the functioning of living beings. The most complex organisms, such as human beings, have several levels of organization: they are made up successively of organs, tissues, cells, and biomolecules. There are several types of biomolecules including proteins, which are like tiny tools that allow cells to live and interact with their environment. To do this, proteins must come into contact with each other in a very precise and determined way. This thesis tests the existence of long-range electrodynamic forces which would allow them to interact in a rapid and guided way, by studying the absorption or emission of this type of wave by proteins, then the diffusion of these proteins in solution to observe their behavior.
698

Contribuições à geração de tráfego fractal por meio da transformada wavelet. / Constributions for fractal traffic generation by wavelest transform.

Lund, Isabelle Reis 26 June 2008 (has links)
Estudos mostraram que o tráfego nas redes de dados tanto locais quanto de grande área, possui propriedades fractais como dependência de longa duração - Long-Range Dependence (LRD) e auto-similaridade. Devido à heterogeneidade de aplicações nessas redes, os traces de tráfego podem apresentar dependência de longa duração - Long Range Dependence (LRD), dependência de curta duração - Short Range Dependence (SRD) ou uma mistura de LRD com SRD. Sendo assim, este trabalho tem como objetivo sintetizar séries temporais gaussianas com flexibilidade de processamento no plano tempo-frequência a serem inseridas num gerador de tráfego com as características estatísticas específicas do tráfego encontrado em redes por comutação de pacotes reais, como autossimilaridade, LRD e SRD. Para isto foram desenvolvidos dois métodos para síntese de séries temporais gaussianas com LRD e simultânea introdução de SRD em diferentes faixas de frequência: Discrete Wavelet Tansform (DWT) com mapa de variâncias e Discrete Wavelet Packet Tansform (DWPT). Estes métodos utilizaram o mapa de variâncias cujo conceito foi desenvolvido neste trabalho. A validação dos métodos foi feita através de análise estatística e comparação com resultados de séries geradas pelo método Discrete Wavelet Transfom (DWT) de Backar utilizado em [1]. Além disso, também foi validada a ideia de que a DWPT é mais interessante que a DWT por ser mais flexível e prover uma maior flexibilidade de processamento no plano tempo-frequência. / Studies demonstrated that the data network traffic of Local Area Network (LAN) and Wide Area Network has fractal properties as long range dependence (LRD) and self-similarity. The traffic traces can show long range dependence, short range dependence or the both behaviors because of applications heterogeneity in these networks. This work objective is to synthetisize gaussian time series with processor flexibility in the time-frequency plan to be inserted in a traffic generator with the specific statistical traffic characteristics of real packet networks such as selfsimilarity, long range dependence (LRD) and short range dependence (SRD). Two methods were developed for the gaussian time series with LRD and SRD synthesis: Discrete Wavelet Tansform (DWT) with variance map and Discrete Wavelet Packet Tansform (DWPT). These methods used the variance map which concept was developed in this work. The methods validation was done by statistic analysis and comparison with the time series generated by the B¨ackar Discrete Wavelet Transfom (DWT) used by [1]. Besides of this, the idea that the DWPT is more because of its processing flexibility in the time-frequency plan was validated.
699

Uso do espaço do marsupial Caluromys philander (Didelphimorphia, Didelphidae) no Parque Nacional da Serra dos Órgãos - Rio de Janeiro, Brasil / Space use by Woolly opossum Caluromys philander (Didelphimorphia; Didelphidae) in Serra dos Órgãos Nacional Park - Rio de Janeiro, Brasil

Bernardo Silveira Papi 21 February 2011 (has links)
Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro / Uso do espaço é um padrão bem estudado em ecologia. Entretanto, formação de área de vida e posição relativa dos abrigos com área de uso são pouco estudados, principalmente para marsupiais didelfídeos. Dentre estes animais, podemos destacar Caluromys philander, devido ao seu baixo registro em armadilhas na Mata Atlântica e características peculiares dentro do grupo, como seu desenvolvimento, longevidade e hábito alimentar. Neste estudo foram investigadas as formações das áreas de uso destes animais através da comparação com seus movimentos diários, e a posição dos seus abrigos dentro das suas áreas de uso. Para isso foram monitorados seis indivíduos de C. philander através de colares rádio transmissores. Estes indivíduos se deslocaram em média 534 153 m por noite. Além disso, apresentaram área diária de 9548 3591 m e área de vida de 2,8 0,4 ha. Noventa e sete por cento das áreas diárias apresentaram sobreposição entre si, com média de 19,4% de sobreposição. Não houve diferença nos locais dos abrigos dos indivíduos monitorados, dentro dos seus Mínimos Polígonos Convexos. Entretanto, estes mesmos abrigos não estiveram localizados nas áreas de maior intensidade de uso. A média de abrigos utilizados por indivíduo foi de 6,3 (3-10) com utilização média de 2,9 (1-17) vezes em cada abrigo, sendo que 48% das vezes os animais só possuíram um registro em cada abrigo, demonstrando baixa fidelidade. Entretanto, dois indivíduos apresentaram diferença de utilização entre seus abrigos, com três destes sendo mais utilizados que os outros. O trabalho sugere que os indivíduos de C. philander monitorados apresentam área de vida propriamente dita (restrita), onde ocorrem as sobreposições entre suas áreas diárias. C. philander utilizam mais de um abrigo em suas vidas, trocando com frequência de abrigos, apesar de alguns destes abrigos poderem ser mais utilizados que outros. Além disso, os abrigos destes animais não são localizados nas suas áreas de maior intensidade de uso. / Use of space is a well studied topic in ecology. However, the structuring of the home range and shelters position, have not received enough attention, especially for didelphid marsupials. One of these, Caluromys philander, is an interesting species because of its low record in traps studies in the Atlantic Forest and its unique characteristics among marsupials related to development, longevity and feeding habits. The present study analyses how daily movements can contribute to the home range formation and how the shelters are positioned within the home range of these animals. Six individuals of C. philander were equipped with radio transmitters necklaces and followed during the night. These individuals moved 534 153 m in average per night. They also had daily ranges of 9548 3591 m and home ranges of 2.8 0.4 ha. There was a 97% overlap between days, with an average of 19.4%. There was no difference in shelters positions and Minimum Convex Polygon areas, although these same shelters were not located in the areas with the greatest use intensity. The average number of shelters used per individual was 6.3 (3-10), with an average of 2.9 (1-17) records per shelter, where shelters were used only one time in 47% of the cases, suggesting low shelter fidelity of these animals. However, two individuals showed difference of shelters use, with three of those being used more than the others. Therefore, I conclude that these individuals of C. philander have real home ranges, where they concentrate their daily movements. C. philander uses more than one shelter in its life, changing shelters frequently, although some shelters can be more used than others. Forthermore, shelters were not located in the areas with the greatest use intensity.
700

Contribuições à geração de tráfego fractal por meio da transformada wavelet. / Constributions for fractal traffic generation by wavelest transform.

Isabelle Reis Lund 26 June 2008 (has links)
Estudos mostraram que o tráfego nas redes de dados tanto locais quanto de grande área, possui propriedades fractais como dependência de longa duração - Long-Range Dependence (LRD) e auto-similaridade. Devido à heterogeneidade de aplicações nessas redes, os traces de tráfego podem apresentar dependência de longa duração - Long Range Dependence (LRD), dependência de curta duração - Short Range Dependence (SRD) ou uma mistura de LRD com SRD. Sendo assim, este trabalho tem como objetivo sintetizar séries temporais gaussianas com flexibilidade de processamento no plano tempo-frequência a serem inseridas num gerador de tráfego com as características estatísticas específicas do tráfego encontrado em redes por comutação de pacotes reais, como autossimilaridade, LRD e SRD. Para isto foram desenvolvidos dois métodos para síntese de séries temporais gaussianas com LRD e simultânea introdução de SRD em diferentes faixas de frequência: Discrete Wavelet Tansform (DWT) com mapa de variâncias e Discrete Wavelet Packet Tansform (DWPT). Estes métodos utilizaram o mapa de variâncias cujo conceito foi desenvolvido neste trabalho. A validação dos métodos foi feita através de análise estatística e comparação com resultados de séries geradas pelo método Discrete Wavelet Transfom (DWT) de Backar utilizado em [1]. Além disso, também foi validada a ideia de que a DWPT é mais interessante que a DWT por ser mais flexível e prover uma maior flexibilidade de processamento no plano tempo-frequência. / Studies demonstrated that the data network traffic of Local Area Network (LAN) and Wide Area Network has fractal properties as long range dependence (LRD) and self-similarity. The traffic traces can show long range dependence, short range dependence or the both behaviors because of applications heterogeneity in these networks. This work objective is to synthetisize gaussian time series with processor flexibility in the time-frequency plan to be inserted in a traffic generator with the specific statistical traffic characteristics of real packet networks such as selfsimilarity, long range dependence (LRD) and short range dependence (SRD). Two methods were developed for the gaussian time series with LRD and SRD synthesis: Discrete Wavelet Tansform (DWT) with variance map and Discrete Wavelet Packet Tansform (DWPT). These methods used the variance map which concept was developed in this work. The methods validation was done by statistic analysis and comparison with the time series generated by the B¨ackar Discrete Wavelet Transfom (DWT) used by [1]. Besides of this, the idea that the DWPT is more because of its processing flexibility in the time-frequency plan was validated.

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