• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.13 no.6
• /
• pp.3055-3073
• /
• 2019

In this paper, a new user identification method is presented using real environmental human-computer-interaction (HCI) behavior data to improve method usability. User behavior data in this paper are collected continuously without setting experimental scenes such as text length, action number, etc. To illustrate the characteristics of real environmental HCI data, probability density distribution and performance of keyboard and mouse data are analyzed through the random sampling method and Support Vector Machine(SVM) algorithm. Based on the analysis of HCI behavior data in a real environment, the Multiple Kernel Learning (MKL) method is first used for user HCI behavior identification due to the heterogeneity of keyboard and mouse data. All possible kernel methods are compared to determine the MKL algorithm's parameters to ensure the robustness of the algorithm. Data analysis results show that keyboard data have a narrower range of probability density distribution than mouse data. Keyboard data have better performance with a 1-min time window, while that of mouse data is achieved with a 10-min time window. Finally, experiments using the MKL algorithm with three global polynomial kernels and ten local Gaussian kernels achieve a user identification accuracy of 83.03% in a real environmental HCI dataset, which demonstrates that the proposed method achieves an encouraging performance.

• Proceeding of Spring/Autumn Annual Conference of KHA
• /
• 2002.11a
• /
• pp.345-348
• /
• 2002

Recent demographic changes have increased the heterogeneity of user groups in the housing market. Smaller households(e.g. elderly, single parent) have non-traditional spatial requirements that cannot be accommodated within the conventional house layout. This has created renewed interest in Demountable/Flexible housing systems. However, the process by which designers decide which project or user groups are most suited for the use of these systems is quite often complex, uncertain and dynamic, since the decisions involve natural processes and human values that are apparently random. This study is a proposal on the design process model for the flexibility of apartment.

• Proceedings of the Korean Society of Broadcast Engineers Conference
• /
• 2008.11a
• /
• pp.189-192
• /
• 2008

Modern broadcasting/multicasting networks has the heterogeneous nature in terms of terminals and available bandwidth. Such heterogeneity could be coped by scalable video coding (SVC) standard developed recently. More specifically, spatial layers of an SVC bitstream can be consumed by different terminals and SNR (and temporal) scalability can be used to cope with bandwidth heterogeneity. In this work, we tackle the problem of SVC adaptation for different user groups receiving the same broadcast/multicast video, so as to provide a flexible tradeoff between the groups while also maximizing the overall quality of the users. The adaptation process to truncate an SVC bitstream is first formulated as an optimization problem. Then the problem is represented by MPEG-21 DIA description tools, which can be solved by a universal processing. The results show that MPEG-21 DIA is useful to enable automatic and interoperable adaptation in our scenario.

• The Journal of the Korea Contents Association
• /
• v.14 no.7
• /
• pp.29-44
• /
• 2014

To provide context aware service, certain phenomena and situation information of the user should be detecting and monitoring using sensors. But, the sensor data has heterogeneity about system, syntax, structure, and semantics. So, it is difficult to apply to various services. To solve this issue, we should remove these heterogeneities and convert to context information that is easy to provide context aware services. Also, the existing context aware service mash-up environment require relevant sensor type, criteria of context, programing ability to define the service situation. So, it is difficult to create service for a non-technical user. Therefore, we propose ontology based user-centric service environment to provide context aware IoT services. It provide context awareness and user-desired services using data that acquired via IoT paradigm. The proposed environment consist of the ontology based semantic sensor data processing and the user-centric service environment. It provide convert the object data to the context information and service mash-up process to create user service in easy way.

• International journal of advanced smart convergence
• /
• v.6 no.3
• /
• pp.29-37
• /
• 2017

The current behavior recognition system don't match data formats between sensor data measured by user's sensor module or device. Therefore, it is necessary to support data processing, sharing and collaboration services between users and behavior recognition system in order to process sensor data of a large capacity, which is another formats. It is also necessary for real time interaction with users and behavior recognition system. To solve this problem, we propose fog cloud based behavior recognition system for human body sensor data processing. Fog cloud based behavior recognition system solve data standard formats in DbaaS (Database as a System) cloud by servicing fog cloud to solve heterogeneity of sensor data measured in user's sensor module or device. In addition, by placing fog cloud between users and cloud, proximity between users and servers is increased, allowing for real time interaction. Based on this, we propose behavior recognition system for user's behavior recognition and service to observers in collaborative environment. Based on the proposed system, it solves the problem of servers overload due to large sensor data and the inability of real time interaction due to non-proximity between users and servers. This shows the process of delivering behavior recognition services that are consistent and capable of real time interaction.

• Proceedings of the IEEK Conference
• /
• 2002.07a
• /
• pp.121-124
• /
• 2002

The proxy mechanism widely used in WWW systems offers low-delay data delivery by means of "proxy server". By applying the proxy mechanisms to the video streaming system, we expect that high-quality and low-delay video distribution can be accomplished without introducing extra load on the system. In addition, it is effective to adapt the quality of cached video data appropriately in the proxy if user requests are diverse due to heterogeneity in terms of the available bandwidth, end-system performance, and user′s preferences on the perceived video quality. We have proposed proxy caching mechanisms to accomplish the high-quality and highly-interactive video streaming services. In our proposed system, a video stream is divided into blocks for efficient use of the cache buffer. The proxy server is assumed to be able to adjust the quality of a cached or retrieved video block to the request through video filters. In this paper, to verify the practicality of our mechanisms, we implemented them on a real system and conducted experiments. Through evaluations from several performance aspects, it was shown that our proposed mechanisms can provide users with a low-latency and high-quality video streaming service in a heterogeneous environment.

• Journal of Computing Science and Engineering
• /
• v.7 no.3
• /
• pp.204-210
• /
• 2013

We present the motivation, design and implementation of a smart home system in Korea. Our system is open, extensible, integrated, intelligent, and usage-centric. We detail the challenges and key design requirements for the smart home system based on our past experiences, and show how convergence system design is a capable methodology for enabling an integrated and multi-faceted home management system that encompasses energy management, home appliance control, environment management, u-health, and living support functionalities under a single unified design. Using energy management as a specific case study, we demonstrate how convergence system design can encapsulate technology heterogeneity and hardware-software disparity without compromising simple yet powerful user interfaces.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.12 no.1
• /
• pp.248-268
• /
• 2018

The performance of smartphone applications are usually constrained in user interactions due to resource limitation and it promises great opportunities to improve the performance by exploring the smartphone built-in and embedded sensing techniques. However, heterogeneity in techniques, semantic gap between sensor data and usable context, and complexity of contextual situations keep the techniques from seamless integration. Relevant studies mainly focus on feasibility demonstration of emerging sensing techniques, which rarely address both general architectures and comprehensive technical solutions. Based on a proposed functional model, this investigation provides a general architecture to deal with the dynamic context for context-aware automation and decision support. In order to take advantage of the built-in sensors to improve the performance of mobile applications, an ontology-based method is employed for context modelling, linguistic variables are used for heterogeneous context presentation, and semantic distance-based rule matching is employed to customise functions to the contextual situations. A case study on mobile application authentication is conducted with smartphone built-in hardware modules. The results demonstrate the feasibility of the proposed solutions and their effectiveness in improving operational efficiency.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2016.10a
• /
• pp.375-378
• /
• 2016

The difficulty of "information sharing", "information reusing" issues happening in Wireless Sensor Network is due to the heterogeneity of the application environment, data processing, communication protocol etc. Based on the introduction of the Ontology theory, though analyzing the sensor characteristic a general type of sensor ontology contains the definition of concept, frame structure and OWL design was proposed from the standpoint of sensor observation. The paper expounded a system framework of the domain ontology through the expansion of knowledge base on the general sensor could achieve the information sharing and reuse by semantic communication between the general sensor ontology and user. The research of this method would bring new idea to the semantic sensor network construction.

• Journal of Smart Tourism
• /
• v.2 no.3
• /
• pp.31-38
• /
• 2022

Understanding demand for travel websites can help hoteliers better evaluate their own multi-channel distribution and reputation management strategies. In this study, we estimated demand for eight major travel websites based on the user percentage in 3,120 U.S. counties. Results highlighted the importance of four types of factors: sociodemographic, economic, Internet use-related, and travel-related. Differences between websites were also compared based on estimated coefficients. For example, the demand for Expedia.com appeared to be driven by age, education background, income, and foreign travel history, whereas the demand for Hotels.com was driven by the proportion of the African American population and domestic travel history. Lastly, implications are provided.