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The use of Machine Learning for malware detection is essential to counter the massive growth in malware types compared with the traditional signature-based detection system. However, machine learning models could also be extremely vulnerable and sensible to transferable adversarial example (AE) attacks. The transfer AE attack does not require extra information from the victim model such as gradient information. Researchers explore mainly 2 lines of transfer-based adversarial example attacks: ensemble models and ensemble samples. \\ Although comprehensive innovations and progress have been achieved in transfer AE attacks, few works have investigated how these techniques perform in malware data. Besides, generating adversarial examples on an android APK file is not as easy and convenient as it is on image data since the generated AE of malware should also remain its functionality and executability after perturbation. Therefore, it is urgent to validate whether previous methodologies could still have their effect on malware considering the differences compared to image data. \\ In this thesis, we first have a thorough literature review for the AE attacks on malware data and general transfer AE attacks. Then we design our algorithm for the transfer AE attack. We formulate the optimization problem based on the intuition that the contribution evenness of features towards the final prediction result is highly correlated to the AE transferability. We then solve the optimization problem by gradient descent and evaluate it through extensive experiments. Implementing and experimenting with the state-of-the-art AE algorithms and transferability enhancement techniques, we analyze and summarize the weaknesses and strengths of each method. / Master of Science / Machine learning models have been widely applied to malware detection systems in recent years due to the massive growth in malware types. However, these models are vulnerable to adversarial attacks. Malicious attackers can add some small imperceptible perturbations to the original testing samples and mislead the classification results at a very low cost. Research on adversarial attacks would help us gain a better understanding of the attacker's side and inspire defenses against them. Among all adversarial attacks, the transfer-based adversarial example attack is one of the most devastating attacks since it does not require extra information from the targeted victim model such as gradient information or query from the model. Although plenty of researchers has explored the transfer AE attack lately, few works focus on malware (e.g., Android) data. Compared with image data, perturbing malware is more complicated and challenging since the generated adversarial examples of malware need to remain functionality and executability. To validate how transfer AE attack methods perform on malware, we implement the state-of-the-art (SOTA) works in this thesis and experiment with them on real Android data. Besides, we develop a new transfer-based AE attack method based on the contribution of each feature for generating AE. We then do comprehensive evaluations and draw comparisons between SOTA works and our proposed method.

In model-driven engineering, powerful query/view languages exist to compute result sets/views from underlying models. However, to use these languages effectively, one must understand the query/view language concepts as well as the underlying models and metamodels structures. Consequently, it is a challenge for domain experts to create queries/views due to the lack of knowledge about the computer-internal abstract representation of models and metamodels. To better support domain experts in the query/view creation, the goal of this paper is the presentation of a generic concept to specify queries/views on models without requiring deep knowledge on the realization of modeling languages. The proposed concept is agnostic to specific modeling languages and allows the query/view generation by-example with a simple mechanism for filtering model elements. Based on this generic concept, a generic query/view language is proposed that uses role-oriented modeling for its non-intrusive application for specific modeling languages. The proposed language is demonstrated based on the role-based single underlying model (RSUM) approach for AutomationML to create queries/views by-example, and subsequently, associated viewtypes to modify the result set or view.

This thesis considers possible criteria for the selection of example sentences for difficult or unknown words in reading texts for students of German as a Second Language (GSL). The examples are intended to be provided within the context of an Intelligent Computer-Aided Language Learning (ICALL) Vocabulary Learning System, where students can choose among several explanation options for difficult words. Some of these options (e.g. glosses) have received a good deal of attention in the ICALL/Second Language (L2) Acquisition literature; in contrast, literature on examples has been the near exclusive province of lexicographers. The selection of examples is explored from an educational, L2 teaching point of view: the thesis is intended as a first exploration of the question of what makes an example helpful to the L2 student from the perspective of L2 teachers. An important motivation for this work is that selecting examples from a dictionary or randomly from a corpus has several drawbacks: first, the number of available dictionary examples is limited; second, the examples fail to take into account the context in which the word was encountered; and third, the rationale and precise principles behind the selection of dictionary examples is usually less than clear. Central to this thesis is the hypothesis that a random selection of example sentences from a suitable corpus can be improved by a guided selection process that takes into account characteristics of helpful examples. This is investigated by an empirical study conducted with teachers of L2 German. The teacher data show that four dimensions are significant criteria amenable to analysis: (a) reduced syntactic complexity, (b) sentence similarity, provision of (c) significant co-occurrences and (d) semantically related words. Models based on these dimensions are developed using logistic regression analysis, and evaluated through two further empirical studies with teachers and students of L2 German. The results of the teacher evaluation are encouraging: for the teacher evaluation, they indicate that, for one of the models, the top-ranked selections perform on the same level as dictionary examples. In addition, the model provides a ranking of potential examples that roughly corresponds to that of experienced teachers of L2 German. The student evaluation confirms and notably improves on the teacher evaluation in that the best-performing model of the teacher evaluation significantly outperforms both random corpus selections and dictionary examples (when a penalty for missing entries is included).

Estudamos exemplos de métricas Finsler simétricas e não-simétricas em S^n, CP^n e HP^n com uma quantidade finita de geodésicas fechadas ou com uma quantidade pequena de geodésicas fechadas \"curtas\". São os chamados exemplos de Katok. Usamos como referência o artigo \"Geometry of the Katok examples\" de Wolfgang Ziller. Verificamos que existem métricas Finsler cujo número de geodésicas fechadas é 2n (no caso de S^ e S^), n(n+1) (no caso de CP^n) e 2n(n+1) (no caso de CP^n). Tais exemplos são construídos numa vizinhança qualquer da métrica Riemanniana canônica dessas variedades. / We study examples of symmetric and non-symmetric Finsler metrics on S^n, CP^n and HP^n with a finite number of closed geodesics or with a small number of \"short\" closed geodesics. These are the well known Katok\'s examples. We use Ziller\'s article Geometry of the Katok examples. We exhibit Finsler metrics whose number of closed geodesics is 2n (in the case of S^ and S^), n(n+1) (in the case of CP^n) and 2n(n+1) (in the case of HP^n). Such examples are found in any neighborhood of the canonical Riemannian metric on these manifolds.

Classé, en 1988, parmi les quatre pédagogues les plus influents du XXe siècle par l’UNESCO, Anton Makarenko demeure paradoxalement un « illustre inconnu » dans la recherche pédagogique francophone. Là où les études russes et allemandes abondent et, depuis plusieurs décennies déjà, contribuent à remettre en question la figure mythifiée de Makarenko diffusée par la propagande soviétique, la recherche francophone semble s’en être arrêtée au portrait « officiel » du pédagogue et, plus étonnamment encore, à l’image fictionnelle qu’en délivre son chef-d’œuvre : le Poème pédagogique. Partant de ce constat, notre recherche se propose d’examiner, en deux temps — « un pédagogue de fiction ? » et « une fiction de pédagogue ? » — les divers usages de la fiction inhérents à la vie et l’œuvre d’Anton Makarenko. Quand la première partie de notre thèse s’attache à comprendre les enjeux de la constitution, de la propagation et de la réception d’une représentation magnifiée du pédagogue soviétique — tâchant, à son terme, d’en reconstruire une biographie critique —, la seconde, elle, s’intéresse à l’œuvre fictionnelle de Makarenko et s’interroge, en particulier, sur les logiques présidant au choix de la fiction pour son Poème. Si elle prétend en éclairer les raisons contextuelles en présentant une traduction inédite de la correspondance entre le pédagogue et son mentor Maxime Gorki, en procédant à une analyse rhétorique du Poème, elle cherche à préciser les rouages et les effets escomptés de ce choix. Mais à travers la figure paradigmatique d’Anton Makarenko et son œuvre phare, ce que souhaite interroger plus généralement notre recherche c’est la nature des rapports inextricables qui lient fiction et pédagogie. La fiction n’est-elle d’ailleurs pas nécessaire à la pédagogie ? Tour à tour révélation, exaltation, mobilisation, contestation, anticipation, elle est aussi, comme ce qu’elle relate, une édification. / In 1988, due to UNESCO decision Anton Makarenko was recognized as one of the four most influential pedagogues in the 20th century, however he paradoxically remains as a «man of mystery » in french pedagogical research. If russian and german studies abound and help to question, since decades, the mythical figure of Makarenko disseminated by Soviet propaganda, the french research seems to have stopped at the "official" portrait of the pedagogue and, even more surprisingly, at his fictional picture that delivers his masterpiece: The Pedagogical Poem. Based on this previous observation, our research propose to examine in two parts — « a fictional pedagogue? » and « a pedagogue of fiction ? » — the various uses of fiction in the life and the work of Anton Makarenko.The first part of our thesis attempts to understand the issues of the creation, the propagation and the reception of a mythologized representation of the soviet pedagogue and to rebuild a critical biography of Makarenko. The second part focuses on the fictional work of Makarenko and questions particularly the logic behind the choice of the fiction for his Poem. It claims, on one hand, to explain the contextual reasons for this choice with a new translation of correspondence between the pedagogue and his mentor Maxim Gorky. Secondly, it seeks to clarify the arcana and the expected effects of this choice through a rhetorical analysis of the Poem.But behind the paradigmatic figure of Anton Makarenko and his masterpiece, this research tries to question, more generally, the nature of the inextricable links between fiction and pedagogy. In a way, isn’t the fiction necessary to pedagogy ? Revelation, exaltation, mobilization, protest, anticipation, it is also an edification.

Estudamos exemplos de métricas Finsler simétricas e não-simétricas em S^n, CP^n e HP^n com uma quantidade finita de geodésicas fechadas ou com uma quantidade pequena de geodésicas fechadas \"curtas\". São os chamados exemplos de Katok. Usamos como referência o artigo \"Geometry of the Katok examples\" de Wolfgang Ziller. Verificamos que existem métricas Finsler cujo número de geodésicas fechadas é 2n (no caso de S^ e S^), n(n+1) (no caso de CP^n) e 2n(n+1) (no caso de CP^n). Tais exemplos são construídos numa vizinhança qualquer da métrica Riemanniana canônica dessas variedades. / We study examples of symmetric and non-symmetric Finsler metrics on S^n, CP^n and HP^n with a finite number of closed geodesics or with a small number of \"short\" closed geodesics. These are the well known Katok\'s examples. We use Ziller\'s article Geometry of the Katok examples. We exhibit Finsler metrics whose number of closed geodesics is 2n (in the case of S^ and S^), n(n+1) (in the case of CP^n) and 2n(n+1) (in the case of HP^n). Such examples are found in any neighborhood of the canonical Riemannian metric on these manifolds.

This thesis presents a learning based approach for detecting classes of objects and patterns with variable image appearance but highly predictable image boundaries. It consists of two parts. In part one, we introduce our object and pattern detection approach using a concrete human face detection example. The approach first builds a distribution-based model of the target pattern class in an appropriate feature space to describe the target's variable image appearance. It then learns from examples a similarity measure for matching new patterns against the distribution-based target model. The approach makes few assumptions about the target pattern class and should therefore be fairly general, as long as the target class has predictable image boundaries. Because our object and pattern detection approach is very much learning-based, how well a system eventually performs depends heavily on the quality of training examples it receives. The second part of this thesis looks at how one can select high quality examples for function approximation learning tasks. We propose an {em active learning} formulation for function approximation, and show for three specific approximation function classes, that the active example selection strategy learns its target with fewer data samples than random sampling. We then simplify the original active learning formulation, and show how it leads to a tractable example selection paradigm, suitable for use in many object and pattern detection problems.

The example based processing problem can be expressed as: "Given an example of an image or video before and after processing, apply a similar processing to a new image or video". Our thesis is that there are some problems where a single general algorithm can be used to create varieties of outputs, solely by presenting examples of what is desired to the algorithm. This is valuable if the algorithm to produce the output is non-obvious, e.g. an algorithm to emulate an example painting's style. We limit our investigations to example based processing of images, video, and 3D models as these data types are easy to acquire and experiment with. We represent this problem first as a texture synthesis influenced sampling problem, where the idea is to form feature vectors representative of the data and then sample them coherently to synthesize a plausible output for the new image or video. Grounding the problem in this manner is useful as both problems involve learning the structure of training data under some assumptions to sample it properly. We then reduce the problem to a labeling problem to perform example based processing in a more generalized and principled manner than earlier techniques. This allows us to perform a different estimation of what the output should be by approximating the optimal (and possibly not known) solution through a different approach.

Changes in the workplace and impending shortages of organizational leaders make it imperative that HRD professionals develop a better understanding of the developmental processes of emergent leaders entering the workplace. While leader development research within the field of HRD has typically focused on established workers, the research in this study assumes a lifespan approach to leader development. This study contributes to the development of the field by examining the leadership experiences of 18 to 20 year olds who were leaders of organizations in high school and how these experiences shaped the identities of these emergent leaders. Themes that emerged related to their experiences included their relationships with others, how they led by example, the development of authentic leadership qualities, and their motivation to lead in new venues. Implications for practice and future research are identified.