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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.
271

Side Channel Analysis of a Java-­based Contactless Smart Card

Mateos Santillan, Edgar January 2012 (has links)
Smart cards are widely used in different areas of modern life including identification, banking, and transportation cards. Some types of cards are able to store data and process information as well. A number of them can run cryptographic algorithms to enhance the security of their transactions and it is usually believed that the information and values stored in them are completely safe. However, this is generally not the case due to the threat of the side channel. Side channel analysis is the process of obtaining additional information from the internal activity of a physical device beyond that allowed by its specifications. There exist different techniques to attempt to obtain information from a cryptosystem using other ways than the normally permitted. This thesis presents a series of experiments intended to study the side channel from a particular type of smart card, known as Java Cards. This investigation uses the well known technique, Correlation Analysis, and a new type of side channel attack called fast correlation in the frequency domain to study the side channel of Java Cards. This research presents a giant magnetoresistor (GMR) probe and for the first time, this type of sensor is used to investigate the side channel. A novel setup designed for studying the side channel of smart cards is described and two metrics used to evaluate the analysis results are presented. After testing the GMR probe and methodology on electronic devices executing the Advanced Encryption Standard (AES), such as 8 bit microcontrollers and 128 bit AES implementations on FPGAs, these techniques were applied to analyse two different models of Java Cards working in the contactless mode. The results show that successful attacks on a software implementation of AES running on both models of Java Cards are possible.
272

Demand Side Management in Deutschland zur Systemintegration erneuerbarer Energien

Ladwig, Theresa 10 July 2018 (has links) (PDF)
Durch den Ausbau an Wind- und PV-Anlagen in Deutschland wird der Flexibilitätsbedarf im Stromsystem steigen. Der Flexibilitätsbedarf kann zum einen durch verschiedene Technologien, z.B. Speicher oder Netze, und zum anderen durch die Stromnachfrage bereitgestellt werden. Eine gezielte Steuerung der Stromnachfrage wird als Demand Side Management (DSM) bezeichnet. Der zunehmend wetterabhängigen und fluktuierenden Stromerzeugung in Deutschland steht jedoch eine bis heute weitgehend unelastische Nachfrage gegenüber. In der Literatur sind verschiedene Arbeiten zu finden, die das Potential zur Lastabschaltung und verschiebung in Deutschland untersuchen. Hierbei liegt der Fokus auf absoluten Werten. Saisonale oder tageszeitliche Unterschiede bleiben dabei häufig unberücksichtigt. Die vorliegende Dissertation greift an dieser Stelle an und untersucht das Potential ausgewählter DSM-Anwendungen in stündlicher Auflösung. Die Ergebnisse zeigen, dass das verfügbare Potential starken saisonalen und tageszeitlichen Schwankungen unterliegt. Dementsprechend wird das DSM-Potential überschätzt, wenn nur absolute Werte betrachtet werden. Darüber hinaus zeigt die Autorin, welche Entwicklungen in den nächsten Jahren hinsichtlich der Verfügbarkeit des DSM-Potentials zu erwarten sind. Basierend auf der Potentialermittlung wird in der Dissertation die Rolle von DSM in einem EE-geprägten Stromsystem modellbasiert untersucht. Hierfür wird das lineare Optimierungsmodell ELTRAMOD, das den deutschen und europäischen Strommarkt abbildet, weiterentwickelt. Anhand verschiedener Szenarien wird zum einen der Beitrag von DSM zur Systemintegration von erneuerbaren Energien in Deutschland und zum anderen die Wechselwirkungen mit anderen Flexibilitätsoptionen (z.B. Speicher) untersucht. Die Ergebnisse zeigen, dass die DSM-Kategorien Lastabschaltung und verschiebung nur kurzzeitig auftretende Schwankungen der Einspeisung aus erneuerbaren Energien ausgleichen können. Zum Ausgleich großer Überschussmengen aus erneuerbaren Energien sind hingegen Power-to-X-Technologien, z.B. Power-to-Heat, besser geeignet.
273

Analyses historique, structurelle et typologique du musical américain à travers les comédies musicales de L. Bernstein / An historical, structural and typological analysis of the American musical, regarding L. Bernstein's musicals

Weisser, Julie 03 December 2016 (has links)
Cette thèse porte sur la comédie musicale américaine des décennies 1940 et 1950 à Broadway, illustrée par le répertoire du compositeur Leonard Bernstein. L'enjeu est d'analyser les différents mécanismes internes et externes de création des œuvres de cette époque. La comédie musicale étant un genre vivant à la croisée du théâtre, de la musique et de la danse, nous avons choisi de l'étudier selon plusieurs démarches : historique, structurelle, et typologique. D'un point de vue méthodologique, cette thèse s'appuie notamment sur l'analyse narrative et musicale de 156 musicals, et des trois comédies musicales de L. Bernstein en particulier. Dans un premier temps, la thèse se concentre sur la comédie musicale à Broadway dans les décennies 1940 et 1950, en explicitant les marqueurs historiques, narratifs, musicaux et chorégraphiques du genre. Dans un second temps, la thèse analyse le répertoire des musicals de L. Bernstein dans sa globalité, en interrogeant d'une part le style de l'artiste, et d'autre part la cohérence des œuvres entre elles et avec les canons mis en évidence dans la partie précédente. Enfin, l'étude de la comédie musicale On the Town (1944) explicite la genèse de l'œuvre, ses caractéristiques musicales et chorégraphiques, et la réception publique et critique du spectacle. / This dissertation deals with the American Broadway musical during the 1940's and the 1950's, illustrated by Leonard Bernstein's works. Our concern is to study the various internal and external processes of creation of these pieces during this period. As the Broadway musical is a lively genre overlaying theatre, music and dance, we chose to study it through multiple angles: through its history, its structure and its typology. From a methodological point of view, this dissertation will rely on the narrative and musical analysis of 156 musicals, and especially three of L. Bernstein's musicals. First this dissertation will focus on Broadway's musicals during the 1940's and the 1950's, and will clarify the genre's historical, narrative, musical and choreographic markers. Secondly we will study L. Bernstein's own musicals. We will make explicit the composer's style, and put to test the consistency of his works amongst themselves and with the genre's canons. Last but not least, our analysis of the musical On the Town (1944) we will highlight the show's genesis, its musical and choreographic markers, and its public and critical reception.
274

Exploratory study of market entry strategies for digital payment platforms

Marcinkowska, Anna January 2018 (has links)
The digital payment industry has become one of the fastest evolving markets in the world, but in the wake of its rapid advancement, an ever increasing gap between academic theory and the actual reality of this market widens - and especially so when it comes to entry theory. It is widely acknowledged that the world is moving towards an ever more homogeneous economy, but despite the fact that payment preferences differ greatly from country to country - research on this subject continues to revolve mainly around localized efforts. But as historical inequalities between poor and rich societies continue to dissipate - learning from nations at the forefront of technological advancement increases the likelihood that the developed strategy becomes applicable to an increased number of countries. By selecting a nation most conducive to technological growth, the purpose of this report is to map the present dynamics in its digital payment industry using both recent and traditional market entry theory. However, studies geared towards globalized strategy formulation cannot be assumed as having guaranteed access to internal company-data at all times. So in order to facilitate such studies, the level of dependency on primary data required for conducting such research needs to be understood first, which is why the work in this report is constrained strictly to data of secondary nature. This, not only to further map the characteristics of this market, but also to see how open the market is to public inspection. Ultimately, the academic contribution becomes that of providing a road-map towards adapting currently available market entry theory to suit the rapidly evolving conditions of the digital payment industry from a global perspective and, when failing to do so, the aim is to also explore avenues for further research towards this end goal.
275

O Avesso e o Direito da escritura camusiana: de L\'Êtranger aos Écrits de Jeunesse / The Wrong Side and The Right Side of camusian scripture: From LÉtranger to Écrits de Jeunesse.

Samara Fernanda Almeida Oliveira de Locio e Silva Geske 02 September 2011 (has links)
LÉtranger e Le Mythe de Sisyphe fazem parte do que Camus nomeou de ciclo do absurdo,no qual se unem sob esse mesmo tema a escrita literária e a reflexão filosófica. O absurdo é essencialmente definido como um divórcio do homem com o mundo, mas encontramos no percurso filosófico do autor uma noção anterior a essa, as núpcias. A análise de todos os textos anteriores ao ciclo do absurdo nos mostra, porém, que núpcias e absurdo sempre fizeram parte da reflexão camusiana. Essas duas noções opostas sempre conviveram juntas, formando o que chamamos de o avesso e o direito, ideia que se reflete no título da primeira recolha de ensaios do autor. O objetivo dessa dissertação é, através de todos os escritos anteriores à narrativa, definir o avesso e o direito como um tema fundamental para a escritura de LÉtranger, onde se conjugam as núpcias e o absurdo, a literatura e a filosofia. / LÉtranger and Le Myth de Sisyphe make part of what Camus named as the absurd cycle, where the literary writing and the philosophical reflection are joined together under the same theme. The absurd is essentially definite as a divorce of man with the world, but we meet in the authors philosophical course a previous notion to it, the nuptials. The analysis of all former texts to the absurd cycle, show us, nevertheless, that nuptials and absurd always were part of camusian reflection. These two opposite notions always lived together, shaping what we call the wrong side and the right side, the title of the authors first reunion of essays. The purpose of this dissertation is, through the all writings written before the narrative, definite the wrong side and the right side as a fundamental theme to the scripture of LÉtranger, where the nuptials and the absurd, the literature and philosophy are joined together.
276

Outils d'aide à la recherche de vulnérabilités dans l'implantation d'applications embarquées sur carte à puce

Andouard, Philippe 18 December 2009 (has links)
Les travaux présentés dans cette thèse ont pour objectif de faciliter les évaluations sécuritaires des logiciels embarqués dans les cartes à puce. En premier lieu, nous avons mis au point un environnement logiciel dédié à l'analyse de la résistance d'implémentations d'algorithmes cryptographiques face à des attaques par analyse de la consommation de courant. Cet environnement doit être vu comme un outil pour rechercher des fuites d'information dans une implémentation en vue d'évaluer la faisabilité d'une attaque sur le produit réel. En second lieu, nous nous sommes intéressé à l'analyse de programmes écrits en langage d'assemblage AVR dans le but de vérifier s'ils sont vulnérables aux \textsl{timing attacks}. Nous avons donc développé un outil qui consiste à décrire des chemins du flot de contrôle d'un programme grâce à des expressions régulières qui seront par la suite interprétées par notre outil afin de donner leur temps exact d'exécution (en terme de cycles d'horloge). Enfin, nous avons étudié comment faciliter la compréhension de programmes écrits en langage C dans le but de vérifier si des politiques de sécurité sont correctement implémentées. D'une part, nous fournissons des assistants de navigation qui au travers d'informations concernant les variables et procédures rencontrées, facilitent la compréhension du programme. D'autre part, nous avons au point une manière de vérifier les politiques de sécurité sans modélisation préalable (e.g. avec un automate à états finis) au moyen de requêtes exprimées dans la logique CTL. / The work presented in this thesis aims at easing the evaluation process of smartcards embedded software. On one hand, we set up a software environment dedicated to analyze the implementation resistance of cryptographic to power analysis attacks. This environment must be seen as a tool that facilitates a real attack by giving a way to find information leakages in an implementation. On the other hand, we focused on analyzing program written in AVR assembly language in order to check whether they are vulnerable to timing attacks. To achieve this goal we have developed a tool that makes possible the description of a path in the control flow of the program thanks to regular expressions. Those regular expressions will be interpreted by our tool in order to give the exact execution timing (expressed in clock cycles). Finally, we studied how to ease the global comprehension of a program written in C language in order to check whether security policies are well implemented. First, we provide graphical navigation assisants that helps to understand the progam being analyzed by giving information on variables and procedures. Then, we provide a way to check the security policies through the use of requests expressed with the CTL logic. This approach does not need prior modelisation of the program.
277

A supply-side model of the South African economy: critical policy implications

Du Toit, Charlotte Barbara 04 January 2007 (has links)
Please read the abstract in the section 00front of this document / Thesis (D Com (Econometrics))--University of Pretoria, 2007. / Economics / unrestricted
278

Comparaisons entre groupes, anonymat, et performances cognitives : expérimentations dans les environnements numériques et en coprésence / intergroup comparison, anonymity, and cognitive performance : experiments in a web-based learning environment and in the presence of others

Le Hénaff, Benjamin 20 June 2016 (has links)
L’objectif de cette thèse est d’étudier comment l’identification à un groupe peut conduire à de meilleures performances cognitives en s’appuyant sur la théorie de l’identité sociale (Tajfel & Turner, 1986). Cette théorie avance que l’identité sociale d’un individu repose en partie sur la comparaison entre son groupe d’appartenance et un autre groupe. La quête d’une identité sociale positive pousserait l’individu à agir pour le bien de son groupe afin de se placer dans une position avantageuse par rapport à un autre groupe. Le modèle SIDE (Social Identity model of Deindividuation Effects, Reicher, Spears & Postmes, 1995) a étendu cette théorie en considérant que l’anonymat facilite le passage de l’identité personnelle à l’identité sociale et la renforce. Notre recherche a été déclinée en trois axes. Les deux premiers ont examiné l’effet de l’anonymat et de la comparaison entre groupes sur les performances à des exercices d’informatique et de statistiques réalisés en environnements numériques. Le dernier axe a étudié les effets de l’anonymat et de la comparaison entre groupes à une tâche de production d’idées créatives en situation de coprésence. Conformément aux prédictions du modèle SIDE, les résultats ont montré que la comparaison intergroupe en situation d’anonymat active l’identité sociale des membres d’un groupe et les conduits à avoir de meilleures performances à des tâches cognitives. De plus, nous avons mis en évidence que des différences individuelles, comme le niveau de connaissances antérieures, viennent modérer les effets du modèle SIDE. Les implications pratiques et théoriques de ces résultats sont discutées, et des pistes de recherches futures sont proposées. / The aim of this thesis is to study how group identification may lead to better cognitive performance, based on social identity theory (Tajfel & Turner, 1986). This theory states that the social identity of individuals is partly based on comparison of their group with another group. The search for a positive social identity should drive individuals to act on behalf of their own group, putting them in an advantageous position compared to another group. The SIDE Model (Social Identity model of Deindividuation Effects, Reicher, Spears & Postmes, 1995) extends this theory by postulating that anonymity could facilitate the transition from personal to social identity, which is reinforced in the process. Our study was organized along three lines of research. The first two examined how anonymity and intergroup comparison affects performance on computer quizzes and statistics exercises in a web-based learning environment. The third studied the effects of anonymity and intergroup comparison on the generation of creative ideas in the presence of others. Consistent with the SIDE Model, we found that intergroup comparison under anonymity conditions activated group members’ social identity, leading to better performance on cognitive tasks. We also found that individual differences, such as prior knowledge, may moderate the effects of the SIDE model. The practical and theoretical implications of these results are discussed, and future research directions are suggested.
279

Development Of A Knowledge-Based Hybrid Methodology For Vehicle Side Impact Safety Design

Srinivas, CH Kalyan 11 1900 (has links) (PDF)
The present research work has been carried out to develop a unified knowledge-based hybrid methodology combining regression-based, lumped parameter and finite element analyses that can be implemented in the initial phase of vehicle design resulting in a superior side crash performance. As a first step, a regression-based model (RBM) is developed between the injury parameter Thoracic Trauma Index (TTI) of the rear SID and characteristic side impact dynamic response variables such as rear door velocity (final) and intrusion supplementing an existing RBM for front TTI prediction. In order to derive the rear TTI RBM, existing public domain vehicle crash test data provided by NHTSA has been used. A computer-based tool with a Graphical User Interface (GUI) has been developed for obtaining possible solution sets of response variables satisfying the regression relations for both front and rear TTI. As a next step in the formulation of the present hybrid methodology for vehicle side impact safety design, a new Lumped Parameter Model (LPM) representing NHTSA side impact is developed. The LPM developed consists of body sub-systems like B-pillar, front door, rear door and rocker (i.e. sill) on the struck side of the vehicle, MDB, and “rest of the vehicle” as lumped masses along with representative nonlinear springs between them. It has been envisaged that for the initial conceptual design to progress, the targets of dynamic response variables obtained from RBM should yield a set of spring characteristics broadly defining the required vehicle side structure. However, this is an inverse problem of dynamics which would require an inordinate amount of time to be solved iteratively. Hence a knowledge-based approach is adopted here to link the two sets of variables i.e., the dynamic response parameters (such as average door and B-pillar velocities, door intrusion, etc.) and the stiffness and strength characteristics of the springs present in LPM. In effect, this mapping is accomplished with the help of an artificial neural network (ANN) algorithm (referred to as ANN_RBM_LPM in the current work). To generate the required knowledge database for ANN_RBM_LPM, one thousand cases of LPM chosen with the help of the Latin Hypercube technique are run with varying spring characteristics. The goal of finding the desired design solutions describing vehicle geometry in an efficient manner is accomplished with the help of a second ANN algorithm which links sets of dynamic spring characteristics with sets of sectional properties of doors, B-pillar and rocker (referred as ANN_LPM_FEM in the current work). The implementation of this approach requires creation of a knowledge database containing paired sets of spring characteristics and sectional details just mentioned. The effectiveness of the hybrid methodology comprising both ANN_RBM_LPM and ANN_LPM_FEM is finally illustrated by improving the side impact performance of a Honda Accord finite element model. Thus, the unique knowledge-based hybrid approach developed here can be deployed in real world vehicle safety design for both new and existing vehicles leading to enormous saving of time and costly design iterations.
280

BASES PARA LA GESTIÓN INTEGRADA DE PEZOTHRIPS KELLYANUS (BAGNALL) (THYSANOPTERA: THRIPIDAE) EN CÍTRICOS

Planes Insa, Laura 10 August 2016 (has links)
[EN] Pezothrips kellyanus (Bagnall) (Thysanoptera: Thripidae) is a new citrus pest in the Mediterranean basin. Nymphs of P. kellyanus refuge and feed on the surface of young fruitlets. This feeding habit causes rings of tissue scar around the apex as fruit mature and leads to economic losses because of the reduced market value of the affected fruit. Despite the worldwide distribution and economic importance of P. kellyanus, its biological control is still under development and chemical control is the only alternative for growers. In order to improve the integrated management of P. kellyanus we determined the seasonal trend of P. kellyanus nymphs during the period in which the young fruitlets are sensitive to thrips damage. We studied the diurnal distribution of ¿rst and second generation P. kellyanus nymphs, as well as, the spatial distribution within the tree of the nymphs and damages. These results will improve the sampling protocols and the insecticide applications. The seasonal trend (number of generations attacking the fruit) and damages of P. kellyanus nymphs depended on the orchards and years. This result emphasizes the importance of sampling weekly from petal until six weeks later. Furthermore, according to the data obtained, when there is a second generation of P. kellyanus nymphs, this is generally more damaging. Pezothrips kellyanus nymphs showed a clear preference for fruit located at the top of the trees, which coincided with the highest percentage of damaged fruit in this area. P. kellyanus nymphs were uniformly distributed and the cardinal directions and time of day does not seem to be an important factor to develop a sampling plan or to spray insecticides. The next objective was to determine the efficacy of three insecticides (chlorpyrifos, spinosad and spirotetramat) to control P. kellyanus nymphs. These insecticides were selected because of their different mode of action. Chlorpyrifos and spinosad significantly reduced the percentage of damaged fruit when there was one generation of nymphs. However, their persistence was not enough to prevent the attack of a second generation of nymphs. Spirotetramat had not a shock effect against this pest and it could not avoid the attack of a second generation. We analysed the side effects of these three insecticides on natural enemies present at the time of the treatment. Spinosad as spirotetramat negatively affected phytoseiids. Due to low populations of other natural enemies we could not assess the side effects on them. Therefore, we decided to study the side effects of these insecticides on coccinelids and parasitoids under laboratory conditions. Lethal and sublethal side effects of spirotetramat on adults and larvae of Cryptolaemus montrouzieri Mulsant (Coleoptera: Coccinellidae) were evaluated under laboratory conditions by topical application and by ingestion of treated individuals of Planococcus citri Risso (Hemiptera: Pseudococcidae). Spirotetramat resulted harmless when directly applied on larvae and adults of C. montrouzieri, since it did not affect survival, longevity, fecundity, egg hatching, and offspring survival. When larvae and adults of C. Montrouzieri were fed with treated prey, spirotetramat was also classified as harmless. We studied lethal and sublethal effects of spirotetramat, spinosad and chlorpyrifos on Aphytis melinus DeBach (Aphelinidae Hymenoptera), the main parasitoid of Aonidiella aurantii (Maskell) (Hemipteta: Diaspididae). For A. melinus adults, chlorpyrifos and spinosad were classified as toxic but spirotetramat resulted moderately toxic. For immature (larvae), chlorpyrifos was moderately toxic, spirotetramat was slightly toxic and spinosad resulted harmless. Takin into consideration these results, spirotetramat could be used against P. kellyanus in orchards where population levels are low and an application against A. aurantii is also need because this insecticide shows high efficacy against this pest. / [ES] Pezothrips kellyanus (Bagnall) (Thysanoptera: Thripidae) es actualmente una plaga más en los cítricos valencianos, cuyas ninfas, al alimentarse de la superficie de los frutos recién cuajados, producen unas escarificaciones circulares alrededor del pedúnculo que devalúan el valor del fruto en el mercado. Hoy en día, el control químico es prácticamente la única alternativa contra este trips. Para mejorar la gestión integrada de P. kellyanus es necesario un mayor conocimiento sobre su biología y ecología en campo. Para ello, se ha seguido la dinámica poblacional de las ninfas de P. kellyanus durante el periodo en que los frutos recién cuajados son más sensibles a los daños producidos por las ninfas. Se ha estudiado la distribución de la plaga dentro de los árboles y su movimiento a lo largo del día, factores necesarios para estimar la población de trips y para afinar las aplicaciones de productos fitosanitarios. Tanto la dinámica como los daños variaron según parcelas y años. Tras la caída de pétalos se observaron una o dos generaciones de ninfas que produjeron daños en los frutos. Resultado que subraya la necesidad de realizar muestreos semanales desde la caída de pétalos hasta incluso después del tratamiento contra la primera generación. Además, según los datos obtenidos, cuando se da una segunda generación de P. Kellyanus, ésta es más dañina para los frutos. Las ninfas de P. kellyanus mostraron una preferencia por los frutos situados en la parte alta de la copa, coincidiendo con el mayor número de frutos dañados en esta zona. La distribución de las ninfas fue uniforme en las cuatro orientaciones del árbol y a lo largo del día. Por lo tanto, estos factores no parecen ser claves a la hora de desarrollar un plan de muestreo o realizar aplicaciones fitosanitarias. A continuación se determinó la eficacia de tres insecticidas (clorpirifos, spinosad y spirotetramat), con diferente modo de acción, en el control de las ninfas de P. kellyanus. Clorpirifos y spinosad redujeron significativamente el porcentaje de frutos dañados cuando se dio una sola generación de ninfas P. Kellyanus, sin embargo no evitaron el ataque de una segunda generación de ninfas. Spirotetramat no presentó un efecto de choque y no evitó el segundo ataque. En estos trabajos de campo, se analizaron los efectos secundarios de los insecticidas sobre los enemigos naturales presentes en el momento de los tratamientos. Spinosad como spirotetramat afectaron negativamente a las poblaciones fitoseidos en campo. Debido a las bajas poblaciones del resto de enemigos naturales no pudo evaluarse los efectos secundarios sobre ellos y se estudiaron en condiciones de laboratorio sobre coccinélidos y parasitoides. Se determinaron los efectos letales y subletales de spirotetramat en adultos y larvas de Cryptolaemus montrouzieri Mulsant (Coleoptera: Coccinellidae), por aplicación directa de los productos y por ingestión de presa, Planococcus citri Risso (Hemiptera: Pseudococcidae), previamente tratada por los productos. Spirotetramat resultó inocuo al aplicarse directamente sobre larvas o adultos de C. montrouzieri, y no afectó a la supervivencia, longevidad fecundidad, fertilidad y y supervivencia de la descendencia. Spirotetramat también resultó inocuo al alimentar a adultos y larvas de C. montrouzieri con presa previamente tratada. Se determinaron los efectos letales y subletales de los tres insecticidas sobre Aphytis melinus DeBach (Hymenoptera: Aphelinidae), principal parasitoide de Aonidiella aurantii (Maskell) (Hemipteta: Diaspididae) en cítricos. En adultos, clorpirifos y spinosad resultaron tóxicos mientras que spirotetramat resultó moderadamente tóxico. Sobre inmaduros de A. melinus, clorpirifos resultó moderadamente tóxico, spirotetramat ligeramente tóxico y spinosad inocuo. Así, spirotetramat se podría utilizar contra P. kellyanus en parcelas con niveles poblacionales bajos cuando deba tratarse también cont / [CAT] Pezothrips kellyanus (Bagnall) (Thysanoptera: Thripidae) és, actualment, una plaga més dels cítrics valencians. Les nimfes es refugien i s'alimenten de la superfície dels fruits recentment quallats que produeix unes escarificacions circulars al voltant del peduncle del fruit i devaluen el seu valor al mercat. Hui en dia, el control químic és pràcticament l'única alternativa contra aquest trips. Per poder millorar la gestió integrada de P. kellyanus és necessari un major coneixement sobre la seua biologia i ecologia en camp. Per a això, s'ha avaluat la dinàmica poblacional de les nimfes de P. kellyanus durant el període on els fruits recentment quallats són més sensibles als danys produïts per les nimfes. A més, s'ha estudiat la distribució de la plaga dins dels arbres i el seu moviment al llarg del dia, factors necessaris per a estimar la població de trips i per afinar les aplicacions de productes fitosanitaris. Tant la dinàmica com els danys van variar segons parcel¿les i anys, després de la caiguda de pètals es van observar una o dues generacions de nimfes que van produir danys als fruits. Aquest resultat subratlla la necessitat de realitzar mostrejos setmanals des de la caiguda de pètals fins i tot després del tractament contra la primera generació. Segons les dades obtingudes, quan es dóna una segona generació de P. kellyanus, aquesta és més perjudicial per als fruits. Les nimfes van mostrar un clara preferència pels fruits situats a la part alta de la copa, coincidint amb el major nombre de fruits danyats en aquesta zona. No obstant això, la distribució de les nimfes va ser uniforme en les quatre orientacions de l'arbre i la seva abundància tampoc va variar al llarg del dia. Per tant, son factors que no semblen ser claus a l'hora de desenvolupar un pla de mostreig o realitzar aplicacions fitosanitàries. El següent objectiu va ser determinar l'eficàcia de tres insecticides (clorpirifos, spinosad i spirotetramat), amb acció diferent, en el control de les nimfes de P. kellyanus. Clorpirifos i spinosad van reduir significativament el percentatge de fruits danyats quan es va donar una sola generació de nimfes, però no varen evitar l'atac d'una segona generació de nimfes. Spirotetramat no va presentar un efecte de xoc contra aquesta plaga i tampoc va evitar l'atac d'una segona generació. En aquests treballs de camp, se va analitzar els efectes secundaris d'aquests tres insecticides sobre els enemics naturals presents en el moment dels tractaments. Spinosad i spirotetramat van afectar negativament les poblacions fitoseids en camp. Com varen ser baixes les poblacions de la resta d'enemics naturals es va estudiar els efectes secundaris sobre coccinélids i parasitoids en condicions de laboratori. Es varen determinar els efectes letals i subletals de spirotetramat en adults i larves de Cryptolaemus montrouzieri Mulsant (Coleoptera: Coccinellidae) per aplicació directa dels productes i per ingestió de presa, Planococcus citri Risso (Hemiptera: Pseudococcidae), prèviament tractada pels productes. Spirotetramat va resultar innocu a la aplicació directa sobre larves o adults de C. montrouzieri, no va afectar la supervivència, longevitat fecunditat, fertilitat i supervivència de la descendència. I el mateix quan adults i larves de van ser alimentats amb presa prèviament tractada. Finalment, es van determinar els efectes letals i subletals dels tres insecticides sobre Aphytis melinus DeBach (Hymenoptera: Aphelinidae), principal parasitoid de Aonidiella aurantii (Maskell) (Hemipteta: Diaspididae) en cítrics. En adults, clorpirifos i spinosad van resultar tòxics, spirotetramat va resultar moderadament tòxic. Sobre immadurs de A melinus, clorpirifos va resultar moderadament tòxic, spirotetramat lleugerament tòxic i spinosad innocu. Així, spirotetramat es podria utilitzar contra P. kellyanus en parcel¿les amb nivells poblacionals baixos aprofitant el tractament contra A. aurantii al p / Planes Insa, L. (2016). BASES PARA LA GESTIÓN INTEGRADA DE PEZOTHRIPS KELLYANUS (BAGNALL) (THYSANOPTERA: THRIPIDAE) EN CÍTRICOS [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/63676 / TESIS

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