• Journal of Korea Multimedia Society
• /
• v.17 no.4
• /
• pp.405-412
• /
• 2014

Due to the popularity of mobile phones, Peer-to-Peer (P2P) content sharing in mobile phones is highly desirable, especially in a mobile data connection. In addition, there has been an increasing demand for content sharing applications for P2P communication in Android-based smartphones as ubiquitous mobile devices. However, due to wireless network limits, unstable characteristic and restricted storage space, mobile users confront challenges in establishing connections and sharing video frames with other users. To solve this issue, we propose an architectural design and implementation of key frame sharing application that uses Chord, a distributed lookup protocol to establish a content sharing platform for mobile devices, combined with the Chord SDK based on Android. Our proposed system enables users easily to share key information on video data in real-time over a wireless network without manual processing of devices which join or leave the group and cost associated with the 3G/4G network.

• Journal of Industrial Technology
• /
• v.27 no.A
• /
• pp.131-139
• /
• 2007

The recent advance in wireless network technologies has enabled the streaming media service on the mobile devices such as PDAs and cellular phones. Since the wireless network has low bandwidth channels and mobile devices are actually composed of limited hardware specifications, the transcoding technology is needed to adapt streaming media to given mobile devices. Futhermore owing to the diversity of bandwidth in the wireless network by reason of mobile users' movements and environments, it is difficult to provide stable QoS. In this paper, the autonomic multimedia transcoding system is proposed in order for users to provide network adaptive QoS. Our proposed system is based on the estimation of available bandwidth in wireless network for seamless multimedia streaming service. The proposed system is designed and implemented for various mobile clients. In experiments, we evaluate its seamless multimedia streaming and the adaptation transcoding bit rate according to the changes of bandwidth in wireless network.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2018.10a
• /
• pp.429-430
• /
• 2018

The introduction of mobile devices increased the need to apply limitations such as mobile devices' memory, speed, energy, and bandwidth on the designs of searching images. There is a demand to reduce such limitations on searching images on the mobile phone. Hence, this paper proposes a design that adds tags on pictures to manage the images in mobile environment, allowing efficient searches and deletion of duplicate files based on the similarities of the images. The proposed method does not compromise its efficiency by increasing costs; it also reduces the volume of data needed for mobile devices.

• The Journal of Information Systems
• /
• v.18 no.3
• /
• pp.27-46
• /
• 2009

Korean society frenzy about ubiquitous computing is in a rapid change into so called 'Nomadic' information environment. In many previous studies, a number of intrinsic and extrinsic motivation factors were empirically found to affect users' continuance to use mobile hand-held devices. However, the role of device attachment, a new intrinsic motivation factor with which users are known to care about their own mobile devices personally, in determining users' post-adoption behavior was not explored yet to the full scale. To fill the research void like this, this study proposes a new research model in which device attachment as well as perceived value are positively linked to satisfaction and continuance to use. The statistical results obtained by applying PLS to the valid 137 questionnaires showed that the device attachment has stronger positive influence on satisfaction and continuance to use than the perceived value. Therefore, a practical implication is suggested thai the mobile devices need 10 be designed in a way of arousing users' device attachment more strongly.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.6 no.5
• /
• pp.1421-1444
• /
• 2012

Mobile devices such as Android devices are emerging as a convenient client computing device with mobility and context-sensing capability. However, the computing power and hardware resource of the devices are limited due to their small form-factor. Consequently, large-scaled applications could not be deployed on these devices. Nonetheless, if the large-scaled applications are deployed and executed on the devices, high performance of the applications cannot be guaranteed. To remedy the limitation in terms of performance, it is inevitable to let some heavy-weight functionality executed on the server side and let a client application invoke the functionality in the server. To realize this kind of mobile applications, we adopt well-defined architecture design principles; being thin-client, being layered with Model-View-Controller (MVC), and being balanced between client side and server side. By adopting the principles, we propose a unique, ideal and practical architecture for mobile applications, called balanced MVC architecture. By considering the principles, key design considerations of realizing balanced MVC architecture lie in functionality partitioning. Hence, we define key criteria of determining the degree of performance. And, we define a method to design a balanced MVC architecture which embodies functionality partitioning for high performance, and a simulation-based evaluation method of balanced MVC architectures.

• International Journal of Contents
• /
• v.8 no.2
• /
• pp.1-6
• /
• 2012

Recently, content-based music information retrieval (MIR) systems for mobile devices have attracted great interest. However, music retrieval systems are greatly affected by background noise when music is recorded in noisy environments. Therefore, we evaluated various pre-processing methods using the Philips method to determine the one that performs most robust music retrieval in such environments. We found that dynamic noise reduction (DNR) is the best pre-processing method for a music retrieval system in noisy environments.

• Proceedings of the Safety Management and Science Conference
• /
• 2009.04a
• /
• pp.451-454
• /
• 2009

The main purpose of this paper is to analyze preference of consumers on mobile devices. Preference analysis was performed on five major brands with five aspects such as commercial image, price, design, function and durability. The result of this study will be helpful for manufactures of mobile devices.

• Journal of the Semiconductor & Display Technology
• /
• v.19 no.1
• /
• pp.23-28
• /
• 2020

In Smart mobile devices embedding big.LITTLE architectures, the conventional multi-core assignment scheme for user applications may incur wasteful energy consumption and long response time. In this paper, we propose a user experience assisted energy-efficient multicore assignment scheme. Our simulation results show that the proposed scheme achieves at 40% less energy consumption and at 20% less response time comparing to the legacy scheme.

• The Journal of Korean Association of Computer Education
• /
• v.12 no.4
• /
• pp.47-55
• /
• 2009

There are many researches considering mobile devices as resources in mobile grids. However, the mobile device has some limitations: wireless connection and battery capacity. So, the grid operations using mobile devices have lower reliability and efficiency than those in fixed grid environments. In this paper, we propose a job migration scheme using mobile devices to overcome these limitations. The proposed job migration scheme predicts failure condition during execution and takes checkpoints. Then, if the failure occurs on mobile device during execution, the executing job can be migrated to other mobile device by checkpoint information. To perform the proposed migration scheme, we establish a mobile device manager on a proxy server and a status manager on a mobile device. Connection, wireless signal strength and battery capacity of mobile devices are identified through two managers. The simulation results show improvement of efficiency and reliability during execution.

• The KIPS Transactions:PartD
• /
• v.12D no.3 s.99
• /
• pp.493-498
• /
• 2005

With the advances of wireless technologies and mobile computing, m-commerce is being realized for several mobile devices such as PDAs and mobile phones. Currently, service contents in m-commerce are usually newly written to meet specific characteristics of the target mobile devices, thus requiring formidable efforts. Therefore, we should exploit the Internet product information currently being provided for e-commerce. However, bringing the Internet product to mobile devices is far from straightforward due to the many limitations of mobile devices such as little memory, small displays, low processing speeds, and so forth. In this paper, we first suggest a new model to effectively adapt the Internet product information for mobile phones. We then suggest a mobile system to implement the model. We then design and implement the system. Finally, we give experiments on the system.