• Journal of the Korea Society of Computer and Information
• /
• v.25 no.8
• /
• pp.23-30
• /
• 2020

As the 4th industrial revolution emerged, the latest technologies such as IoT, AI, Big data, AR/VR/XR are emerging. However, in the field of virtual reality (VR) technology platform services, there is no standardization and systematic support. In addition, various platform technologies related to virtual reality have been presented, making it difficult to select an API that should be selected for development. In this study, we analyzed the method for virtual reality development and the virtual reality (VR) technology that is being serviced by users. In addition, by presenting the advantages and disadvantages of each development platform, we intend to present a reference point for developers to select an efficient platform. In addition, it will help the developer to select an effective equipment and software platform in comparison with the advantages and disadvantages of various HMD devices used in virtual reality. The virtual reality (VR) development environment test used products from Oculus, and the software development environment was tested with two types: WebBased VR and HMD embedded.

• Journal of Digital Contents Society
• /
• v.10 no.1
• /
• pp.87-96
• /
• 2009

Digital Broadcast Service is being very popular and the delivery mechanism for digital broadcast content through IP network has progressed constantly, due to the advance of video and audio compression and network technologies. From these trends, in Korea, the commercial IPTV service starts in this year after the law related to IPTV is enacted last year. Since IPTV service, which integrates broadcast and communication services, can give an infrastructure for fusion of communication and interactive multimedia data service, IPTV service is attractive. Recently, by the advent of various wireless connection technologies and the mobile devices of high capability, Mobile IPTV, which has an advantage of not only IPTV but also mobile TV, has gained much interest. In this paper, we review a necessary ingredient for Mobile IPTV in the next generation wired/wireless convergence network environment which consists of heterogeneous wireless access networks. In addition, we propose the scheme for user mobility and service session mobility management using RTSP protocol and introduce the service gateway concept to guarantee the extension of IPTV service platform.

• Journal of the Korea Society of Computer and Information
• /
• v.18 no.3
• /
• pp.11-18
• /
• 2013

In this paper, we propose a new design scheme of N-Screen emulator based on Cloud and then implement the emulator, in order to solve the critical point of N-Screen emulator based on Cloud. This method, without the emulator in the server, will be able to confirm the features of the emulator with a browser using Web Service. This means that the identical service is possible without regard to personal computer or mobile environment. Also, in order to emulating each different web browser engine of the various devices separately, we revise and manage the WebKit engine to be suitable to the characteristics of each device. In the previous design method, the number of emulators which can be shown in a monitor is restricted to 2 or 3. However, we show that the proposed design method can improve the performance of server to the extent that this method could operate more than 100 emulators per each server.

• Journal of rehabilitation welfare engineering & assistive technology
• /
• v.9 no.3
• /
• pp.203-208
• /
• 2015

In this study, a digital textbook was developed for effective career and vocational education of students with disabilities. The contents of developed digital textbook consisted of 'lesson 15: Sale(1)' of middle school career and vocational education of basic curriculum. It progresses six periods and each topic activities are composed of open learning, learning activity 1, learning activity 2, and organized learning in order. NamoPubTreeEditor Program was used to develop the text book in the study, digital textbooks were designed to be compatible with various devices including smartphone of android operating system, Tablet PC, the iOS system, iphone, ipad, etc. In addition, it was designed to offer a variety of learning materials such as sale multimedia materials, glossary, evaluation questions, and linked data related to sale, supported self-motivated learning. allowed students to evaluate their study for the learning of students with disabilities.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.8 no.3
• /
• pp.91-99
• /
• 2009

Development of high-speed Internet services and the increased supply of mobile devices have become the key factor for the acceleration of ubiquitous technology. WiBro system, formed with lP backbone network, is a MBWA technology which provides high-speed multimedia service in a possibly broader coverage than Wireless LAN can offer. Wireless telecommunication environment needs not only mobility support in Layer 2 but also mobility management protocol in Layer 3 and has to minimize handover latency to provide seamless mobile services. In this paper, we propose a fast cross-layer handover scheme based on signal strength prediction in WiBro environment. The signal strength is measured at regular intervals and future value of the strength is predicted by Exponential Smoothing Method. With the help of the prediction, layer-3 handover activities are able to occur prior to layer-2 handover, and therefore, total handover latency is reduced. Simulation results demonstrate that the proposed scheme predicts that future signal level accurately and reduces the total handover latency.

• Journal of Korea Game Society
• /
• v.9 no.3
• /
• pp.121-128
• /
• 2009

In this paper, we have developed the balance board with electronic devices to use in various fields of remedial and physical balance exercise with interesting game and the functional game. Rehabilitation training using a funny game will be effective for patient's rehabilitation training. A Personal training system uses a balance board with an acceleration sensor and the game controlled by physical balance. To evaluate the operation of the developed system, we developed rehabilitation training game. The proposed game can be applicable to rehabilitation and balance training, and suggested game interface method could use a commercial game with various function through our emulator.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.20 no.2
• /
• pp.394-400
• /
• 2016

Currently, with the rapid development of the digital age, multimedia-related image devices become popular. However image deterioration is generated by multiple causes during the transmission process, with typical example of salt and pepper noise. When the noise of high density is added, existing methods are deteriorated in the characteristics of removal noise. After judging the noise condition to remove the salt and pepper noise, if the center pixel is the non-noise pixel, it is replaced with the original pixel. On the other hand, if it is the noise pixel, algorithm is suggested by the study, where the histogram of the corrupted image and the median filters are used. And for objective judgment, the proposed algorithm was compared with existing methods and PSNR(peak signal to noise ratio) was used as judgment standard. As the result of the simulation, The proposed algorithm shows a high PSNR of 32.57[dB] for Lena images that had been damaged of a high density salt and pepper noise(P=60%), Compared to the existing CWMF, A-TMF and AWMF there were improvements by 21.67[dB], 18.07[dB], and 20.13[dB], respectively.

• The KIPS Transactions:PartA
• /
• v.11A no.6
• /
• pp.425-432
• /
• 2004

Traditional applications are executed using the restricted resources of a single computer, do not consider contextual information, and can not support mobile users. However, ubiquitous applications provide optimal services for mobile users using the various resources of computers and the contextual information around users and devices. Thus, ubiquitous applications need to have the functionality of context awareness, user mobility and QoS adaptability. This paper design the CMQ(Context-aware, Mobility-aware, QoS-aware) middleware framework for ubiquitous applications and implement the middleware framework using Jini and Java. The implemented middleware system can process various contexts, provide the session handoff for a mobile user, and allow applications to adjust its QoS dynamically.

• The KIPS Transactions:PartC
• /
• v.16C no.1
• /
• pp.117-124
• /
• 2009

Recently, the application of network technology extends to all areas because of development of digital information technology. Thus, networks are being evolved towards a next-generation communication environments where all information devices, home appliances, and object are connected and interoperated. In order to provide adequate convergence services in IMS-based networks that are the core technology of the next-generation communication environments, seamless service should be possible although the underlying network and the device in use may change in the networks. In this paper, we propose an efficient architecture, algorithm, and protocol of service session control for seamless service in such networks.

• The KIPS Transactions:PartB
• /
• v.15B no.6
• /
• pp.585-594
• /
• 2008

The issues that we should consider in the process of providing mobile web service using a mobile device are seamless service and QoS-guaranteed service. HMIPv6 has MAP because of improving packet loss and transmission delay due to disconnection. However, a load is concentrated on HMIPv6 because of receiving and delivering packet for MN. Owing to this, real time data fails to be processed quickly, and also adaptive mobile service is required for QoS guaranteed service. However, this method demands the response time cost of contents service owing to the hardware differences of various devices. Therefore, we improve the process performance of real time data by applying a queue in MAP for seamless service in this paper. For decreasing response time cost, we propose mobile web service method which has reusable cache of contents using the elements of contents. The result of a numerical formula and simulation shows that our proposed method is superior under various system conditions.