Limin Gu
共找到 2 条论著文献

1、How will they react if we make them talk? Students』 experiences from learner-created video tasks in online university education in Sweden 2017

摘要:1 online resource. In focus in this paper are students』 views on their experiences of an educational design with oral assessment tasks supported by video technology in online university education in Sweden. Questions targeted how the students perceived the impact of oral tasks on their learning. The data were gathered through questionnaires, qualitative interviews and students』 self-reflection documents. Results indicate most students appreciated the oral assessments, and their descriptions of this learning experience indicate that the studied video-based task-design may enhance online students』 learning experiences.
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2、Revaluation of Error Correcting Coding in Watermarking Channel

摘要:Robustness is one of the most important issues in digital watermarking. By modeling digital watermarking as digital communications, several researchers proposed using error correcting coding (ECC) to improve watermark robustness. However, the following important facts are neglected. i) The robust watermark channel suffers from a very high bit error ratio (BER), which may exceed the capability of ECC; ii) Due to the imperceptibility requirement, the redundancy introduced by ECC will lead to a decrease of the watermark magnitude. Could the usage of ECC effectively improve the robustness of watermark? This paper addresses this problem from the perspectives of both theoretical analysis and experiments. Our investigation shows that ECC cannot effectively improve the robustness of watermarking against a vast majority of various attacks except for cropping and jitter attacks. Hence, ECC should not be considered as a universal method applied to enhance the watermark robustness.
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