442 research outputs found
Aquisição de preposições a e de em contextos de regência verbal, nominal e adjetival: o caso dos aprendentes chineses
A presente dissertação tem como objetivo identificar as dificuldades
encontradas pelos alunos chineses em apreender e usar adequadamente as
preposições a e de em contextos de regência verbal, nominal e adjetival. Para
a realização do estudo, apresenta-se primeiro o enquadramento teórico
necessário ao presente trabalho, incluindo-se uma visão geral das preposições
em Português, refletindo sobre o valor semântico e o emprego das
preposições a e de, introduzindo o conceito de regência e a relação entre
regência e preposição. Referem-se, também, as preposições chinesas, a fim
de identificar as diferenças entre as preposições portuguesas e chinesas. Em
seguida, combinando conceitos como língua materna, interlíngua, análise de
erros, etc., pretende-se analisar as causas das dificuldades dos aprendentes
chineses na aquisição de preposições em Português e identificar problemas
típicos no seu uso. Para tal, elaborou-se um questionário, que foi aplicado a
estudantes chineses de PLE de diferentes níveis e de diferentes Instituições de
ensino. Através da análise dos dados, podemos constatar que os contextos de
regência verbal e adjetival são os mais difíceis e confusos para os aprendentes
chineses. Por fim, apresentam-se algumas estratégias para atenuar as
dificuldades e melhorar a eficiência da aprendizagem das preposições em
Português.This dissertation aims to find out the difficulties of Chinese students in correctly
understanding and using prepositions a and de in the context of verbal, nominal
and adjectival regency. In order to carry out this research, the theoretical
framework involved in this work is first introduced, such as the general concept
of Portuguese preposition, the semantic value and use of prepositions a and
de, the concept of regency and the relationship between regency and
preposition. Chinese prepositions are introduced for the sake of the
identification of the differences between Portuguese and Chinese prepositions. Combined with linguistic knowledge, such as mother tongue, interlanguage, error analysis, etc., this paper analyzes the causes why Chinese learners have
difficulty in learning Portuguese prepositions and points out typical mistakes. A
questionnaire is prepared specifically for this topic, which is applied to Chinese
PLE students at different levels and from different educational institutions. Through data analysis, we can clearly identify that the use of Portuguese
prepositions in the context of verbal and adjective regency is the most difficult
and confusing. Finally, some strategies are presented to solve the difficulties
and improve the efficiency of learning Portuguese prepositions.Mestrado em Português Língua Estrangeira/Língua Segund
Neural differences between the processing of musical meaning conveyed by direction of pitch change and natural music in congenital amusia
Music is a unique communication system for human beings. Iconic musical meaning is one dimension of musical meaning, which emerges from musical information resembling sounds of objects, qualities of objects, or qualities of abstract concepts. The present study investigated whether congenital amusia, a disorder of musical pitch perception, impacts processing of iconic musical meaning. With a cross-modal semantic priming paradigm, target images were primed by semantically congruent or incongruent musical excerpts, which were characterized by direction (upward or downward) of pitch change (Experiment 1), or were selected from natural music (Experiment 2). Twelve Mandarin-speaking amusics and 12 controls performed a recognition (implicit) and a semantic congruency judgment (explicit) task while their EEG waveforms were recorded. Unlike controls, amusics failed to elicit an N400 effect when musical meaning was represented by direction of pitch change, regardless of the nature of the tasks (implicit versus explicit). However, the N400 effect in response to musical meaning in natural musical excerpts was observed for both groups in both types of tasks. These results indicate that amusics are able to process iconic musical meaning through multiple acoustic cues in natural musical excerpts, but not through direction of pitch change. This is the first study to investigate the processing of musical meaning in congenital amusia, providing evidence in support of the “melodic contour deafness hypothesis” with regard to iconic musical meaning processing in this disorder
Adaptive digital watermarking scheme based on support vector machines and optimized genetic algorithm
Digital watermarking is an effective solution to the problem of copyright protection, thus maintaining the security of digital products in the network. An improved scheme to increase the robustness of embedded information on the basis of discrete cosine transform (DCT) domain is proposed in this study. The embedding process consisted of two main procedures. Firstly, the embedding intensity with support vector machines (SVMs) was adaptively strengthened by training 1600 image blocks which are of different texture and luminance. Secondly, the embedding position with the optimized genetic algorithm (GA) was selected. To optimize GA, the best individual in the first place of each generation directly went into the next generation, and the best individual in the second position participated in the crossover and the mutation process. The transparency reaches 40.5 when GA’s generation number is 200. A case study was conducted on a 256 × 256 standard Lena image with the proposed method. After various attacks (such as cropping, JPEG compression, Gaussian low-pass filtering (3, 0. 5), histogram equalization, and contrast increasing (0.5, 0.6)) on the watermarked image, the extracted watermark was compared with the original one. Results demonstrate that the watermark can be effectively recovered after these attacks. Even though the algorithm is weak against rotation attacks, it provides high quality in imperceptibility and robustness and hence it is a successful candidate for implementing novel image watermarking scheme meeting real timelines
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