• Journal of KIISE
• /
• v.42 no.8
• /
• pp.954-960
• /
• 2015

It is important to improve the performance of storage in the home cloud environment within the virtualized IoT gateway since the performance of applications deeply depends on storage. Though SSD caching is applied in order to improve the storage, it is only used for read-cache due to the limitations of SSD such as poor write performance and small write endurance. However, it is important to improve performance of the write operation in the home cloud server, in order to improve the end-user experience. This paper propose a novel SSD caching which considers write-data as well as read-data. We validate the enhancement in the performance of random-write by transforming it to the sequential patterns.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2013.10a
• /
• pp.324-327
• /
• 2013

Recently, due to evolving cloud computing technology, we can easily and transparently utilize both local computing resource and remote computing resource in real life. Especially, enhancing smart device technologies and network infrastructures promote an increase of needs to share files between local smart devices and cloud storages. However, since smart devices have a limited storage space, storing files on cloud storage causes a starvation problem of local storage. It means that users can face a storage-lack problem even a cloud storage service provide a huge file storing space. In this research, we propose a method to manage files between smart devices and cloud storages. Our approach calculate file usage pattern based on recently used date, and then this approach determines local files being migrated. As a result, our approach is sufficient for handling data synchronization between big data storage farm and local thin client which contains limited storage space.

• The Journal of the Korea Contents Association
• /
• v.17 no.12
• /
• pp.34-48
• /
• 2017

The narratives of the digital age have attempted interactions, and the interactive storytelling represented by the Branch Narratives has a problem of the expensive production cost of many optional implementations and poor narrative compared to linear story. As an alternative to this, this study proposes a user-oriented storytelling using user's personality traits. Using the Enneagram, a model of human psyche, and the Actantial model of the semiotician Greimas, when stories and characters are the same, the story could be reconstructed by deriving different topics from the same story according to the user's Enneagram personality type. The theme is determined by defining the axis of the desire of the Actantial model by respectively setting the character with the user's Enneagram type as the subject and the core value in the type as the object. The axis of Power could be defined by the stress and security points in Enneagram. In this way, we can derive the themes of 9 Enneagram types and the corresponding Actantial model and make plots. The users will appreciate one of these reconstructed plots in different perspectives and themes, depending on their personality type. In this study, we applied the above methodology to the story of the pansori novel "Tokkijeon". User-centered storytelling is a new attempt to predict user's choice and reconstruct the story based on the user's personality and perspective.

• Journal of Digital Convergence
• /
• v.19 no.12
• /
• pp.427-433
• /
• 2021

With the support of the government and public institutions, local government characters achieved a lot of quantitative growth. However, there are very few successful cases such as strengthening local identity and revitalizing the local economy using characters. This paper presents a transmedia storytelling strategy as a way to solve the problem of local government characters. To do so, I identify the problems of the current local government characters, and analyze the preceding studies on the features and components of transmedia contents, and the principles of transmedia storytelling, to develop strategies and yielded the expected effect. The transmedia strategy of local government characters consists of a total of three stages. In the first step, the local identity is established through the development of a unique story to the region. The second step, improve attractivity by renewing character design for various individual media platforms. And lastly the third step, enhance usability by expanding interactivity based on communication and participation of development actors and the public. This paper is meaningful in that it derives a transmedia storytelling strategy from the perspective of brand marketing as a way to revitalize local government characters. Based on the conclusions drawn from this study, a follow-up study is needed to apply it to specific cases of local government characters.

• Journal of the Korea Society of Computer and Information
• /
• v.17 no.11
• /
• pp.53-61
• /
• 2012

Kodu made by MS is a new 3D visual programming language made specifically for creating games. This language is based on creativity, problem-solving methods, and storytelling. So, it is very suitable for game programming education for kids. In this paper, we designed learning method to develop games based on elementary school students' creative thinking. The instruction was given to 27 6-grade elementary school students in 30 hours. And we applied the learning method in class. Also, we analyzed the changes in the learners' creative thinking and the learning effects of game programming.

• KIISE Transactions on Computing Practices
• /
• v.20 no.10
• /
• pp.555-560
• /
• 2014

This paper proposes the data security technology for the desktop virtualization environment using the separated software execution method. In the virtual environment where allocates separate VMs to the users, there is a benefit that the programs in one guest machine are isolated from the programs running in another guest machine, whereas in the separated execution environment that supports application virtualization, the isolation is not offered and it causes the data security problem because the applications are executed by the one root privilege in the server. To solve this problem, we provides the data security method using the server storage filter, the viewer filter, and the file mapping table in this paper.

• Smart Media Journal
• /
• v.4 no.4
• /
• pp.33-38
• /
• 2015

Cloud storage server do not detect duplication of conventionally encrypted data. To solve this problem, Convergent Encryption has been proposed. Recently, various client-side deduplication technology has been proposed. However, this propositions still cannot solve the security problem. In this paper, we suggest a secure source-based deduplication technology, which encrypt data to ensure the confidentiality of sensitive data and apply proofs of ownership protocol to control access to the data, from curious cloud server and malicious user.

• Journal of Digital Convergence
• /
• v.14 no.2
• /
• pp.175-181
• /
• 2016

Cloud storage servers do not detect duplication of conventionally encrypted data. To solve this problem, convergent encryption has been proposed. Recently, various client-side deduplication technology has been proposed. However, this propositions still cannot solve the security problem. In this paper, we suggest a secure source-based deduplication technology, which encrypt data to ensure the confidentiality of sensitive data and apply proofs of ownership protocol to control access to the data, from curious cloud server and malicious user.

• Journal of KIISE
• /
• v.41 no.11
• /
• pp.878-884
• /
• 2014

File I/O buffer cache plays an important role in narrowing the wide speed gap between the main memory and the secondary storage. However, data loss or inconsistencies may occur if the system crashes before the data that has been updated in the buffer cache is flushed to storage. Thus, most operating systems adopt a daemon that periodically flushes dirty data to the secondary storage. In this study, we show that periodic flushes account for 30-70% of the total write traffic to storage and remove this inefficiency by implementing a small, non-volatile buffer cache. Specifically, we present space-efficient management techniques, such as delta-write and fragment-grouping, and show that the storage write traffic and throughput can be improved by a margin of 44.2% and 23.6%, respectively, with only a small NVRAM.

• Journal of Digital Contents Society
• /
• v.18 no.1
• /
• pp.133-139
• /
• 2017

To address the problems caused by such high installation and maintenance cost in the conventional server-based cloud systems, researches on P2P cloud storages have been conducted recently. In this paper, we propose a hierachical overlay structure that can improve the playback quality in P2P cloud storage systems for video transmission. In this structure, after we make groups by clustering the participating peers based on their similarities, we construct subgroups by geographically dividing the peers belonging to a specific group considering the physical proximities among them. Therefore, when a request for video playback is issued, we can minimize the transmission delay by selecting the source peers depending on their locality. By simulations, we show that our proposed hierarchical overlay structure considering the peers' locality outperforms the structure where source peers are selected randomly.