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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.
11

Processamento e análise digital de imagens em estudos da cinética de recristalização de ligas Al-Mg-X / Processing and analysis of digital images in studies of recrystallization kinectics of Al-Mg-X alloys

Juliano da Silva Ignacio 11 November 2013 (has links)
O Processamento e Análise Digital de Imagens é utilizado cada vez mais para agilizar processos, aumentar a precisão, segurança e confiabilidade de dados extraídos de imagens nas mais diversas áreas de pesquisa. No entanto, muitas vezes é necessário que o pesquisador faça, ele próprio, o pré-processamento das imagens, mesmo não sendo um especialista nesta área. Isto coloca em risco o próprio objetivo do uso do Processamento e Análise Digital de Imagens. Este trabalho analisa a relação dos dados extraídos de uma imagem (micrografia) através do software livre ImageJ com relação ao seu processamento final desejado, avaliando assim, a necessidade ou não, de uma ou mais sequencias de pré-processamento para adequar a imagem para o processamento final, indicando ainda quais fatores de influência apresentam informações irrelevantes ou incompletas para o processamento final utilizando ferramentas da Lógica Paraconsistente Anotada. Os resultados obtidos mostram que esta abordagem carece de informações diversificadas sobre a imagem original capturada que possam subsidiar a tomada de decisão quanto aos procedimentos necessários e, para o pré-processamento adequado ao objetivo desejado. / Processing and Analysis of Digital Images is increasingly used to streamline processes, improve accuracy, safety and reliability of data extracted from images in various research areas. However, it is often necessary for the researcher to make himself, the preprocessing of images, although not an expert in this area. This puts at risk the very purpose of using the Processing and Analysis of Digital Images. This paper analyzes the relationship of the data extracted from an image (micrograph) through the free software ImageJ, with respect to its desired final processing. Thus, evaluating the necessity or not, of one or more sequences of preprocessing to adjust the image to the final processing, further indicating which factors influence presents incomplete or irrelevant information for final processing using tools of Annotaded Paraconsistent Logic. The results show that this approach lacks diversified information about the original image captured that can support decision making about procedures for appropriate preprocessing to the desired goal.
12

Induced responses of wheat to aphid feeding : consequences for both sides of the insect-plant interaction /

Gianoli, Ernesto. January 1900 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 1999. / Härtill 5 uppsatser.
13

Evolución del Programa de Salud Bucodental Infantil en la Comunidad Autónoma de Murcia tras 8 años desde su implantación

Eráns Richarte, Óscar 21 October 2011 (has links)
El presente trabajo ha estudiado el periodo incremental del Programa de Asistencia Bucodental Infantil (PADI), implantado en la Comunidad Autónoma de la Región de Murcia en el año 2003, hasta el año 2010, donde terminó su etapa incremental (BORN nº 13, 2003). Sus principales características son: Se realizará de forma incremental a partir del 1 de enero de 2003 con los menores de 6 y 7, que continuarán integrados en el PADI hasta alcanzar los 15 años. A partir del año 2004 se incluiría una nueva una cohorte de edad cada año. Este modelo PADI la financiación es pública, pero la provisión es mixta (pública y privada). El pago a los dentistas privados es por capitación para los tratamientos básicos y por acto médico para los tratamientos especiales. El objetivo principal del Programa es el disminuir la incidencia de caries y enfermedad periodontal de los niños residentes en la Región de Murcia. / The present work has studied the incremental period of the Program of Oral Infantile Assistance (PADI), implanted in the Autonomous Community of the Region of Murcia in the year 2003, until the year 2010, where it finished his incremental stage (BORN n º 13, 2003). His principal characteristics are: There will be realized of incremental form from January 1, 2003 by the child of 6 and 7, that they will continue integrated the PADI up to reaching 15 years. From the year 2004 the new one would include a cohort of age every year. This model PADI the financing is public, but the provision is mixed (public and private). The payment to the private dentists is for capitation for the basic treatments and for medical act for the special treatments. The principal aim of the Program is to reduce the incident of caries and disease periodontal of the resident children in the Region of Murcia.
14

Landscape and farm management influence generalist predators : effects on condition, abundance, and biological control /

Östman, Örjan. January 2002 (has links)
Thesis (doctoral)--Swedish University of Agricultural Sciences, 2002. / Thesis documentation sheet inserted. Appendix reprints five published papers and manuscripts, three co-authored with others. Includes bibliographical references. Also available electronically via World Wide Web in PDF format; online version lacks appendix.
15

Development of a bioinspired NugalBot for precision seeding of rice

Dhani, Harsa 10 December 2021 (has links) (PDF)
Many people around the world live in islands with mountainous lands. These people plant upland rice for their staple food. However, farming in these disadvantageous farms requires high input and gains low yield. One possible solution for improving productivity is by utilizing precision seeding. This study is focused on developing a robot for precision seeding of rice that is suitable for farming in rough terrain. A bioinspired human arm robot for picking seeds and making a hole on the ground was developed in accordance with Aalborg method for bioinspired design. Development of a mobile platform to carry the robot arm was done using hybrid wheel and leg (wheg) wheels and skid steering locomotion. The NugalBot could climb obstacle and perform precision rice seed singulation. However, the performance of the mechanisms for making hole and for covering the hole was dependent on the hardness of the soil.
16

The role of midfield islets in pest control

Sigfridsson, Sabine January 2013 (has links)
During last century rising populations and changed market preferences have led to large structuralchanges in agriculture in the developed world. Most conventional cultivation methods involve theproduction of few monoculture crops within a homogenous landscape, where pesticides and inorganicfertilizers are used to increase yields. The cereal aphid Rhopalosiphum padi (L.) is a pest in cerealsresulting in large economic losses for farmers throughout Europe, and are currently removed withchemical pest control. However, the pesticides also affect existing ecosystem services like potentiallypest-controlling insects as well as the surrounding environment negatively. According to previousstudies higher landscape diversity leads to a higher diversity of natural enemies to pest insects, but nostudy has investigated if the pest control is enhanced around non-crop remnants such as midfield islets(MI). This thesis investigates (i) if MI will reduce the number of aphids in crop field, (ii) if larger MIwill be more effective than smaller MI by having higher aphid predation rate, and (iii) if larger MI willprovide a more effective reduction of pest insects over a longer distance from edge. To assess thepotential for pest control, aphids were glued on papers and placed at ground level in crop fields andaround MI in nine fields. The collected data was processed statistically, and the result demonstratesthat MI play an important role by providing habitats for natural enemies to pests. The increased size ofMI have a positive effect of number of aphids consumed around MI, however the distance from edgewas not significance. This study highlights the value of MI in crop fields as an existing ecosystemservice in biological pest control. The naturally occurring predators are able to reduce R.padi andthereby minimize the need for insecticide applications. / Ökat befolkningstryck och större efterfrågan av jordbruksprodukter på marknaden har det senasteseklet lett till stora förändringar i västvärldens jordbrukslandskap. Odlingslandskapet är idaghomogent och monokulturellt där besprutningsmedel används för att ge större avkastning iproduktionen. Skadeinsekten havrebladlus (Rhopalosiphum padi) angriper vårgrödor vilket leder tillstora ekonomiska förluster för bönder runtom i Europa. Pesticider används för att reducera angreppenmen påverkar även miljön negativt samt existerande ekosystemtjänster, såsom naturliga fiender sombiologiskt kan begränsa skadeinsekters angrepp. Tidigare studier visar att heterogena landskap har enhög biologisk mångfald, men ingen studie har undersökt åkerholmars (ÅH) eventuella potential förbiologisk bekämpning av skadeinsekter i säd. Denna studie undersöker därför (i) om ÅH leder tillökad reducering av havrebladlöss i säd, (ii) om större ÅH är mer effektiva än mindre i frågan ompestreducering, samt (iii) om större ÅH begränsar lusangrepp längre ut i fält från ÅH:s kant än mindreholmar. Studiens hypoteser testades genom experiment utförda i nio fält med vårgrödor där lössklistrades på etiketter som placerades ut i omgivande fält. Dessa samlades in efter tjugo fyra timmarför att studera antal löss konsumerade i relation till ÅH. Det insamlade materialet är bearbetatstatistiskt och resultatet visar att ÅH spelar en betydande ekologisk roll för naturliga fiender tillskadeinsekten havrebladlus. Fler löss konsumerades runt större ÅH än de med mindre yta eller i de fältutan ÅH. Däremot har avståndet från ÅH en mindre betydelse, vilket indikerar att pestreduceringen ärmest effektiv nära stora ÅH. Denna studie synliggör värdet av existerande ÅH som inhysernyttoinsekter i jordbrukslandskapet, samt att heterogena landskap har högre potential för en mernaturlig skadedjursbekämpning. Naturliga fiender är därmed en existerande ekosystemtjänst som kanbegränsa bladlusangreppen (R.padi), som i sin tur ger möjligheten att reducera användandet avbekämpningsmedel, vilket för oss närmare miljömålet ”en giftfri miljö”.
17

Assessing Cereal Aphid Diversity and Barley Yellow Dwarf Risk In Hard Red Spring Wheat and Durum

Haugen, Samuel Arthur McGrath January 2018 (has links)
Barley yellow dwarf (BYD), caused by Barley yellow dwarf virus and Cereal yellow dwarf virus, and is a yield limiting disease of small grains. A research study was initiated in 2015 to identify the implications of BYD on small grain crops of North Dakota. A survey of 187 small grain fields was conducted in 2015 and 2016 to assess cereal aphid diversity; cereal aphids identified included, Rhopalosiphum padi, Schizaphis graminum, and Sitobion avenae. A second survey observed and documented field absence or occurrence of cereal aphids and their incidence. Results indicated prevalence and incidence differed among respective growth stages and a higher presence of cereal aphids throughout the Northwest part of North Dakota than previously thought. Field and greenhouse screenings were conducted to identify hard red spring wheat and durum responses to BYD. Infested treatments in the greenhouse had significantly lower number of spikes, dry shoot mass and yield.
18

Development of a mass rearing technique for the Tasmanian brown lacewing, Micromus tasmaniae Walker

Simeonidis, Andrew January 1995 (has links)
Aphids are one of the most important insect pests of greenhouse crops yet to be controlled by biological means. Broad spectrum chemical control is becoming increasingly difficult to use in integrated pest management programmes, therefore, there is a need for a suitable biocontrol agent to be mass reared and released. The Tasmanian brown lacewing, Micromus tasmaniae Walker is an aphid predator that is found commonly throughout Australasia and has suitable characteristics that make it a candidate for mass rearing. A technique for rearing M. tasmaniae was developed. Eggs of M. tasmaniae were reared in batches of 50, 100 and 200 in 20 litre clear plastic containers. The oat aphid, Rhopalosiphum padi L. was fed to the larvae. The results revealed that the highest initial egg density (200 eggs per container) produced the cheapest adults at 22 cents per adult. However, mass rearing adults was considered not practical because of the high production cost, although, mass production of eggs is considered to be economically viable. The cost of producing one egg was 0.015 cents. M tasmaniae was maintained in mass culture for six generations. Simple experiments were carried out to monitor the quality of laboratory-reared insects. The 'wild' insect was used as a quality standard and comparisons with laboratory-reared insect populations were made. The fecundity, development rates and tolerance to pirimicarb, a carbamate insecticide, were determined. Fecundity was found to decline with successive generations in mass culture. The lacewing development experiment indicated that larval stages of each generation suffered the highest mortality rate and that between 35-45% of individuals emerged as adults. The tolerance of adults to pirimicarb did not alter over five generations. Recommendations for improving the mass rearing of M. tasmaniae are discussed.
19

Strategies of Sexual Reproduction in Aphids / Fortpflanzungsstrategien der Sexuellen Generation von Blattläusen

Dagg, Joachim 30 October 2002 (has links)
No description available.
20

Spinnen in Agrarlandschaften und die biologische Kontrolle von Getreideblattläusen / Spiders in agricultural landscapes and the biological control of cereal aphids

Schmidt, Martin H. 27 May 2004 (has links)
No description available.

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