RMSE-ELM: Recursive Model based Selective Ensemble of Extreme Learning Machines for Robustness Improvement

Extreme learning machine (ELM) as an emerging branch of shallow networks has shown its excellent generalization and fast learning speed. However, for blended data, the robustness of ELM is weak because its weights and biases of hidden nodes are set randomly. Moreover, the noisy data exert a negative effect. To solve this problem, a new framework called RMSE-ELM is proposed in this paper. It is a two-layer recursive model. In the first layer, the framework trains lots of ELMs in different groups concurrently, then employs selective ensemble to pick out an optimal set of ELMs in each group, which can be merged into a large group of ELMs called candidate pool. In the second layer, selective ensemble is recursively used on candidate pool to acquire the final ensemble. In the experiments, we apply UCI blended datasets to confirm the robustness of our new approach in two key aspects (mean square error and standard deviation). The space complexity of our method is increased to some degree, but the results have shown that RMSE-ELM significantly improves robustness with slightly computational time compared with representative methods (ELM, OP-ELM, GASEN-ELM, GASEN-BP and E-GASEN). It becomes a potential framework to solve robustness issue of ELM for high-dimensional blended data in the future.Comment: Accepted for publication in Mathematical Problems in Engineering, 09/22/201

A realização das construções preposicionais na aprendizagem do PLE por alunos de língua materna chinesa

Mestrado em Línguas, Literaturas e CulturasA presente dissertação tem como principal objetivo a apresentação dos erros típicos na aquisição das preposições em português por alunos chineses. No âmbito da linguística contrastiva, esta dissertação propõe uma análise comparativa entre as línguas portuguesa e chinesa, que incidirá sobre o estudo gramatical das preposições como categoria lexical. O trabalho procurará, em primeiro lugar, para cada língua, fornecer um enquadramento teórico da noção de preposição (fraseologia, semântica, regência, etc.) e realizar um levantamento terminológico desta categorial lexical, nomeadamente identificar áreas críticas, como as preposições espaciais ou argumentais, identificando eventuais pontos de convergência e de divergência linguística nas duas línguas. Procurará, em segundo lugar, proceder ao levantamento comparativo das situações de uso das construções preposicionais, por meio de um inquérito destinado a recolher dados com vista à elaboração de um corpus linguístico, procurando dessa forma localizar fenómenos de interferência nesta área. A perspetiva contrastiva adotada deverá levar, desse modo, a algumas conclusões práticas sobre os problemas na utilização das preposições na área da tradução e do ensino de Português e Mandarim aos alunos estrangeiros.The main objective of this dissertation is the presentation of the typical mistakes in the acquisition of Portuguese prepositions by Chinese students. In the context of contrastive linguistics, this dissertation proposes a comparative analysis between the Portuguese and Chinese languages, which will focus on the grammatical study of prepositions as a lexical category. The work will seek, first of all, for each language, to provide a theoretical framework of the notion of preposition (phraseology, semantics, regency, etc.) and to carry out a terminological survey of this lexical category, namely to identify critical areas such as spatial or argumental prepositions , Identifying possible points of convergence and linguistic divergence in the two languages. It will seek, secondly, to carry out a comparative survey of the situations of use of the prepositional constructions, through an inquiry to collect data with a view to the elaboration of a linguistic corpus, seeking in this way to locate phenomena of interference in this area. The contrastive perspective adopted should lead to some practical conclusions about the problems in the accomplishment of the prepositions in the area of translation and teaching of Portuguese and Mandarin to foreign students

Prospective and Practicing Middle School Teachers' Knowledge of Curriculum for Teaching Simple Algebraic Equations

Knowledge of curriculum is a significant component of mathematical knowledge for teaching. However, clearly understanding knowledge of curriculum requires further refinement and substantial research. This study consists of three papers that aim to explore prospective and practicing middle school teachers’ Knowledge of Curriculum for Teaching Simple Algebraic Equations (KCTE). The first paper reviews trends in and the evolution of standards and policies and synthesizes significant findings of research on mathematics curriculum and Knowledge of Curriculum for Mathematics Teaching (KCMT). Through this synthesis, the paper examines policy changes and research relevant to mathematics curriculum and KCMT and anticipates future research approaches and topics that show promise. Building on the context provided by the first paper, the following two papers investigate KCTE from the perspectives of prospective and practicing middle school mathematics teachers. For the second paper, data was collected from a convenience sample of 58 prospective middle school mathematics teachers and a subsample of six participants. The findings of this study identify patterns of key mathematical topics in the teaching sequence of simple algebraic equations, compare the participants’ sequences with experts’, reveal participants’ orientations toward KCTE, draw connections between participants’ KCTE and their knowledge of content and teaching, and establish relationships between participants’ KCTE and their knowledge of content and students. Four middle school mathematics teachers participated in the third study. The results indicate that state-level intended curriculum is the most prevailing component of participants’ KCTE. Furthermore, from a vertical view of curriculum, participants’ awareness of their students’ lack of basic mathematical knowledge impacted their KCTE. The paper also identifies the role of the state-level intended curriculum in participants’ KCTE, alternative approaches to curriculum implementation that participants used to respond to the multiple intelligences of their students, and the participants’ lack of lateral curriculum knowledge in KCTE. Together, these three papers offer a closer look at KCMT with a focus on simple algebraic equations. This research broadens our understanding of prospective and practicing middle school teachers’ KCMT and discusses implications for professional development

Zika Virus Non-structural Protein 4A Blocks the RLR-MAVS Signaling

Flaviviruses have evolved complex mechanisms to evade the mammalian host immune systems including the RIG-I (retinoic acid-inducible gene I) like receptor (RLR) signaling. Zika virus (ZIKV) is a re-emerging flavivirus that is associated with severe neonatal microcephaly and adult Guillain-Barre syndrome. However, the molecular mechanisms underlying ZIKV pathogenesis remain poorly defined. Here we report that ZIKV non-structural protein 4A (NS4A) impairs the RLR-mitochondrial antiviral-signaling protein (MAVS) interaction and subsequent induction of antiviral immune responses. In human trophoblasts, both RIG-I and melanoma differentiation-associated protein 5 (MDA5) contribute to type I interferon (IFN) induction and control ZIKV replication. Type I IFN induction by ZIKV is almost completely abolished in MAVS(-/-) cells. NS4A represses RLR-, but not Toll-like receptor-mediated immune responses. NS4A specifically binds the N-terminal caspase activation and recruitment domain (CARD) of MAVS and thus blocks its accessibility by RLRs. Our study provides in-depth understanding of the molecular mechanisms of immune evasion by ZIKV and its pathogenesis