• Journal of Internet Computing and Services
• /
• v.25 no.1
• /
• pp.49-56
• /
• 2024

There have been emerging many use-cases applying recommendation systems especially in online platform. Although the performance of recommendation systems is affected by a variety of factors, selecting appropriate features is difficult since most of recommendation systems have sparse data. Conventional matrix factorization (MF) method is a basic way to handle with problems in the recommendation systems. However, the MF based scheme cannot reflect non-linearity characteristics well. As deep learning technology has been attracted widely, a deep neural network (DNN) framework based collaborative filtering (CF) was introduced to complement the non-linearity issue. However, there is still a problem related to feature embedding for use as input to the DNN. In this paper, we propose an effective method using singular value decomposition (SVD) based feature embedding for improving the DNN performance of recommendation algorithms. We evaluate the performance of recommendation systems using MovieLens dataset and show the proposed scheme outperforms the existing methods. Moreover, we analyze the performance according to the number of latent features in the proposed algorithm. We expect that the proposed scheme can be applied to the generalized recommendation systems.

• Journal of The Korean Association For Science Education
• /
• v.28 no.7
• /
• pp.768-778
• /
• 2008

The most important factor in students' growth and development is the teacher. Therefore in-service science teacher education to develop the professionality is important as well as the selection of new excellence teachers. Our research is on the development and application of new education program on science experiments where in-service teachers become the lecturers in the program and provide information that is bound to the context of real lessons. This program is consisted of following 10 steps of work, which was implemented in 5 months: sharing the philosophy of the program, selecting science experiments, first application of the experiments, discussion on the first application, learning how to edit the movie clips of the lesson, second application of the experiments, in depth discussion on the second application, developing the experiment package, giving lecture to other science teachers, and evaluating the program. We describe the process of the program developed and implemented in detail to suggest a model of science teacher education program on science experiments and discuss educational implications. This program is characterized by the emphasis of the context closely linked to the real lessons, the problem solving in a real situation, and the collaboration of teachers, professors and science education researcher in a teacher education.

• Journal of Digital Contents Society
• /
• v.11 no.2
• /
• pp.177-184
• /
• 2010

These days, as digital producing technique has been developed, 3D imaging technique is used in high-tech computer and T.V. Also study for 3D producing technique is actively in progress. Moreover, as James Cameron's movie, 'Avatar' released in 2009 was a box office hit, the issue about 3D image came to the fore again. At this point, I decided to study the effect of the visual depth caused by the color correction during the post-production stage. The purpose of this study is to offer information about processing effective images through data about the effect of the visual depth that applies the color correction during the post-production stage. Basically, I supposed that color and contract would have effects on depth of 3D image. As a result, I could find out the changes of visual depth, space perception and sense of depth throughout the experiment. Applying this result,, I produced the 15 minutes of 3D advertisement movie and I found out that the color correction during the post-production stage was very effective for 3D depth. The left image and the right image by beam splitter based rig and parallel rig were used for this study. Also I adjusted the strong contrast by the color correction during the post-production stage after correcting convergence and visual depth during editing. As a result, I could produce images which had strong sense of space and sense of depth.

• The Korean Journal of Archival Studies
• /
• no.43
• /
• pp.5-42
• /
• 2015

Korean wave 3.0 is focused on 'K-Culture' which includes traditional culture, cultural art as well as existing culture contents as a keyword. It considers everything about Korean culture as materials of Korean wave culture contents. Since Korean wave culture contents reflect contemporary social aspect, it needs to preserve those contents as archives and records which have the important value of evidence. With this social environment, this study aims to implement RMS based on AtoM that manages various kinds of Korean wave culture contents through analysis of management situation of those materials. Recently, it is in progress individually to manage them through organizations dealing with korean cultures such as K-Pop, K-Food, K-Movie. However, it has problems in accumulating information and reproducing high quality contents because of lack of coordination among organizations. To solve the problems, this study proposed RMS based on open source software Access to Memory(AtoM) for managing and recording Korean wave culture contents. AtoM provides various functions for managing records and archives such as accumulation, classification, description and browsing. Furthermore AtoM is for free as open source software and easy to implement and use. Thus, this study implemented RMS based on AtoM to methodically manage korean wave culture contents by functional requirements of RMS. Also, this study considered contents relating K-Food as an object to collect, classify, and describe. To describe it, this study selected ISAD(G) standard.

• Journal of Popular Narrative
• /
• v.27 no.1
• /
• pp.13-51
• /
• 2021

As a case study, this paper historicizes the film culture in Namchon district in Keijo(京城) based on a preliminary research on the film ephemera produced during the colonial period. Through cross-examining articles appeared in Japanese newspapers and magazines at the time, this paper empirically reconstructs the Japanese settlers' film culture in Keijo, a colonial city whose cultural environment was ethnically divided into 'Bukchon' and 'Namchon.' During the silent era, movie theaters in the Namchon district not only played a role of cinema chain through which films imported and distributed by Japanese film companies were circulated and exhibited but also served as a cultural community for Japanese settlers who migrated to a colony. The film ephemera issued by each theater not only provided information about the movie program, but also connected these Japaneses settlers in colonial city, Keijo to the homogeneous space and time in Japan proper. Both as a minority and colonizer in a colony, these Japanese settlers experienced a sense of 'unity' that could 'distinguish' their ethnic identity differentiated from Koreans through watching movies in this ethnically segregated cultural environment. In doing so, they were also able to connect themselves to their homeland in Japan Proper, despite on a cultural level. This is a cultural practice that strengthens a kind of long distance nationalism. Examining Japanese film culture through film ephemera would not only contribute to the previous scholarship on modern theater culture and spectatorship established since the 2000s, but also be a meaningful attempt to find ways and directions for film history research through non-film materials.

• Journal of Popular Narrative
• /
• v.27 no.1
• /
• pp.99-130
• /
• 2021

This paper examines printed materials such as weekly newsletters and leaflets issued by Dansungsa, a movie theater in Colonial Korea for a promotional purpose as independent modern media. During the 1920s and 1930s, in tandem with the development of the incipient printing houses in Namchon, Gyeongseong, including Suyeongsa, Dansungsa published promotional prints including weekly newsletters and leaflets in a serial manner to compete with Joseon-gukjang and Umigwan. As these materials contain various information including movie programmes, spectatorship, distributional channels, and promotional strategies that bears witness to theater culture of this time, this paper focuses on the dynamics where not only text and image but also audiences and filmic texts are mediated one another. To this end, the paper has three objectives. First, I argue that weekly newsletters and leaflets can be considered as 'flickering media' that meddles in text and image culture. Second, Dansungsa's promotional prints interpellated film audiences as a loyal fan group while mediating audiences and filmic texts. In doing so, I suggest that these print materials established its own cultural domain differentiated from filmic culture itself. Third, these ephemeral materials contributed to narrowing the gap between colonial Joseon and the World in its imaginary geography through the function of mediation.

• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.46 no.1
• /
• pp.39-44
• /
• 2009

The advance of communication and networking technology enables high bandwidth multimedia data transmission. The development of high performance compression technology such as H.264 also encourages high quality video and audio data transmission. The trend requires efficient protection system for digital media rights. We propose an efficient digital media protection system using elliptic curve cryptography. Only key parameters are encrypted to reduce the burden of complex encryption and decryption in the proposed system, and the digital media are not played back or the quality is degraded if the encrypted information is missing. We need a playback system with an ECC processor to implement the proposed system. We implement an H.264 decoding system with a configurable ECC processor to verify the proposed protection system We verify that the H.264 movie is not decoded without the decrypted information.

• Journal of Information Technology Applications and Management
• /
• v.21 no.4
• /
• pp.203-223
• /
• 2014

This study proposes a novel context-aware recommender system, which is designed to recommend the items according to the customer's responses to the previously recommended item. In specific, our proposed system predicts the user's emotional state from his or her responses (such as facial expressions and movements) to the previous recommended item, and then it recommends the items that are similar to the previous one when his or her emotional state is estimated as positive. If the customer's emotional state on the previously recommended item is regarded as negative, the system recommends the items that have characteristics opposite to the previous item. Our proposed system consists of two sub modules-(1) emotion prediction module, and (2) responsive recommendation module. Emotion prediction module contains the emotion prediction model that predicts a customer's arousal level-a physiological and psychological state of being awake or reactive to stimuli-using the customer's reaction data including facial expressions and body movements, which can be measured using Microsoft's Kinect Sensor. Responsive recommendation module generates a recommendation list by using the results from the first module-emotion prediction module. If a customer shows a high level of arousal on the previously recommended item, the module recommends the items that are most similar to the previous item. Otherwise, it recommends the items that are most dissimilar to the previous one. In order to validate the performance and usefulness of the proposed recommender system, we conducted empirical validation. In total, 30 undergraduate students participated in the experiment. We used 100 trailers of Korean movies that had been released from 2009 to 2012 as the items for recommendation. For the experiment, we manually constructed Korean movie trailer DB which contains the fields such as release date, genre, director, writer, and actors. In order to check if the recommendation using customers' responses outperforms the recommendation using their demographic information, we compared them. The performance of the recommendation was measured using two metrics-satisfaction and arousal levels. Experimental results showed that the recommendation using customers' responses (i.e. our proposed system) outperformed the recommendation using their demographic information with statistical significance.

• Journal of Korea Multimedia Society
• /
• v.15 no.5
• /
• pp.577-586
• /
• 2012

The smartphone emerged due to the rapid development of the Internet has brought greater convenience to life in a positive manner. Recently, however, because of unconstrained exposure to harmful video, reckless use of smart phones has become a domestic issue in our society. In this paper, a service which detects harmful videos by using the acoustic information is designed and implemented on the Android OS. In order to implement the service of Android OS-based detection of the harmful movie, the speed of existing sound-based detection method for harmful videos is improved. The GMM(Gaussian Mixture Model) was used for classifier and the number of Gaussian Mixture was 18. The implemented service shows a detection rate of 97.02% for a total of 1,210 data files (approximately 687 hours) which comprises 669 general videos files (about 424 hours) and 541 harmful video files (about 263 hours). It's speed is 5.6 times faster than the traditional methods whitout reducing the detection rate.

• Journal of KIISE:Computer Systems and Theory
• /
• v.35 no.9_10
• /
• pp.466-475
• /
• 2008

Owing to the improved wireless communication technologies, it is possible to provide streaming service of multimedia with PDAs and mobile phones in addition to desktop PCs. Since mobile client devices have low computing power and low network bandwidth due to wireless network, the transcoding technology to adapt media for mobile client devices considering their characteristics is necessary. Transcoding servers transcode the source media to the target media within corresponding grades and provide QoS in real-time. In particular, an effective load balancing policy for transcoding servers is inevitable to support QoS for large scale mobile users. In this paper, the transcoding load estimation algorithm is proposed for load balance on the distributed transcoding environments. The proposed algorithm estimates transcoding time from transcoding server information, movie information and target transcoding bit-rate. The estimated transcoding time is proved based on experiments.