Media Research Center

About: Media Research Center is a based out in . It is known for research contribution in the topics: Collaborative learning & Educational technology. The organization has 491 authors who have published 950 publications receiving 28581 citations. The organization is also known as: MRC.

Motivated shortcomings in explanation: the role of comparative self-evaluation and awareness of explanation recipient's knowledge.

Abstract: Being aware of someone else's existing knowledge is a prerequisite to effectively adapting an explanation to that person's learning needs. However, such knowledge awareness introduces the potential for motivated self-evaluation based on relative knowledge, that is, for social comparison. Because favorable social comparisons are actively defended, we propose that knowledge awareness might undermine information sharing in explanation when social comparison motives are active. We tested this hypothesis in a series of experiments in which participants provided explanations to an ostensible learning partner with or without knowledge awareness. Both dispositionally and situationally motivated social comparison interacted with knowledge awareness to reduce information sharing in explanation. Intriguingly, knowledge awareness uniformly facilitated adaptation of the information that was shared to address partner knowledge deficit. These results illustrate a tension in the components of effective explanation. At the same time that knowledge awareness effectively coordinates explanation content, it can lead to knowledge hoarding by knowledgeable explainers who are motivated to rely on knowledge differences between the self and the explanation recipient for self-evaluation.

Educational Perspectives on Scripting CSCL

Abstract: This chapter discusses different educational approaches to collaboration scripts. When carefully designed, scripts can push learners to that kind of situations in which meaningful interaction can take place. However, many conditions need to be met for this to happen in authentic classroom contexts. One of the biggest educational challenges in instructional design of computer-supported collaboration scripts is to better integrate them into wider social planes such as overall classroom activities. Scripts could also be considered as contextual and situated resources in collaborative learning environments. Furthermore, a challenge for future research is to explore how external scripts can be gradually replaced by individual self-regulation. In order to face many of these challenges, longer-term follow-up studies should be conducted in research on collaboration scripts.

Audio Information Hiding Based on Spatial Masking

Abstract: Herein an information hiding technique for audio signals is proposed based on the spatial masking phenomenon observed in the human auditory system. This method employs an audio encoding technique called Ambisonics, which has recently received much attention because unlike conventional audio formats that cannot retain precise spatial information, Ambisonics is capable of reproducing sound space. For secrecy, information is hidden as an additive phantom sound source, which should be located near the real one to exploit spatial masking. Thus, only individuals who know the position of the phantom sound source and the key sequence can extract the hidden information. Additionally, computer simulations of common signal processes confirmed that the proposed method is robust against the all tested attacks except for the pitch scaling attack.

Counteracting Implicit Conflicts by Electrical Inhibition of the Prefrontal Cortex.

Abstract: Cognitive conflicts and distractions by task-irrelevant information often counteract effective and goal-directed behaviors. In some cases, conflicting information can even emerge implicitly, withou...

Understanding Disk Carbon Loss Kinetics for Heat Assisted Magnetic Recording

Abstract: An optical pump-probe set-up that allowed short dwell time ( ~ 500 μs) heating with a high-temperature ramp rate ( ~ 106 K/s) was used to detect the magnetization change in heat assisted magnetic recording (HAMR) media. The temperature of the media was monitored by observing the Kerr signal. The pump power at zero magnetization allowed the determination of the power needed to attain the Curie temperature of the media (the Curie temperature was determined with a high-temperature magnetometer before the pump-probe experiments). HAMR media was then irradiated with a pump power to obtain 480°C for increasing exposure times. Atomic force microscopy (AFM) of these media surfaces revealed depressions or holes in the media surface [within the carbon overcoat (COC) layer] that increased in extent with cumulative exposure time. Media surfaces exposed to somewhat lower temperatures (450°C) and for shorter times had a swollen region that surrounded a much smaller depression. High-spatial resolution Raman spectroscopy was used to analyze these irradiated areas. An increased D-band was observed within the swollen portion of the media surface, while the overall Raman signal intensity decreased within the small depressed area. Using time and temperature irradiations along with AFM analysis of the depressions the activation energy for COC loss was determined to be 0.6 eV. These observations were attributed to COC failure through graphitization and oxidation. The failure mechanism leading to these observed changes and the possible relationship of the present results to the HAMR media COC thermal stability are discussed.