• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.3
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• pp.22-33
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• 2014

As a standard of WMNs, IEEE 802.11s supports two kinds of MAC algorithm: a mandatory EDCA used by IEEE 802.11e and an optional MCCA. While EDCA classifies traffic according to four Access Categories (AC) and offer differentiated service using a classified priority, MCCA can guarantee the specific bandwidth of users with a TDMA-style bandwidth reservation scheme between mesh routers. In case that a flow is VBR traffic of a multimedia application, MCCA has disadvantage that the reserved bandwidth does not be used entirely, though it guarantees required bandwidth of users and fairness using bandwidth reservation with neighbors' node. In this paper, we showed a problem that is wastes the reserved bandwidth when MCCA is enabled and proposed a new scheduling algorithm to prevent waste of bandwidth and to improve network utilization effectively, named Resource Sharing Round Robin (RSRR) scheduling. Finally we showed simulation results that performance of a proposed RSRR is better than the legacy MCCA through NS-2 simulation.

• Journal of Broadcast Engineering
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• v.16 no.5
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• pp.797-800
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• 2011

The objective of MPEG Media Transport (MMT), which is on going standard, is to develop efficient delivery of media over packet based networks in an adaptive, progressive, download/streaming fashion over various IP based networks, including terrestrial, satellite and cable broadcast networks. In this paper we introduce utilization of signal strength information based on Cross Layer Design(CLD) to efficient multimedia delivery over wireless network in which in practice the wireless conditions can vary significantly. Many recent studies have shown that a significant improvement in wireless video throughput can be achieved by utilizing signal strength information on CLD [1][2]. Despite of its usefulness, however, it was difficult to employ signal strength information in rate adaptation applications due to different representation of signal strength information for each underlying wireless network. To that end, we proposed syntax and semantics of signal strength information in such a way that the information can be interpreted in the unified way. The proposed signal strength information was proposed for the MMT standardization.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.17 no.5
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• pp.157-163
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• 2017

The binary and interpolation search algorithms are the most famous among search area algorithms, the former running in $O(log_2n)$ on average, and the latter in $O(log_2log_2n)$ on average and O(n) at worst. Also, the interpolation search use only the probability of key value location without priori information. This paper proposes another search algorithm, which I term a 'hybrid block and interpolation search'. This algorithm employs the block search, a method by which MSB index of a data is determined as a block, and the interpolation search to find the exact location of the key. The proposed algorithm reduces the search range with priori information and search the reduced range with uninformed situation. Experimental results show that the algorithm has a time complexity of $O(log_2log_2n_i)$, $n_i{\simeq}0.1n$ both on average and at worst through utilization of previously acquired information on the block search. The proposed algorithm has proved to be approximately 10 times faster than the interpolation search on average.

• Information Systems Review
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• v.16 no.3
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• pp.69-87
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• 2014

The integration of Tourism and Information Communication Technology (ICT) has been continued based on a drastic progress of ICT in the entire sectors of tourism industry. A variety of terminologies such as eTourism, Virtual Tourism, Smart Tourism have appeared during the last decades, however, tourism with Smartphones created a new paradigm has not discussed yet in tourism industry and academia. By investigating on the previous literature in the role of ICT in tourism, we have classified five major streams in the past such as end user perspective (tourist behaviour), Community, Multimedia and Web, Intelligent System, and Smart Tourism. At a result, we investigated the concept of smart tourism and extended to research on Smart Tourism Ecosystems. We suggest the concept of smart tourism ecosystems, which may create values by interacting among tourism players (tourist, distribution channel, supply channel, government, and local community). We propose the discussion of meaning of 'creating shared value' through 'Smart Tourism Ecosystems'.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.9 no.4
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• pp.753-757
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• 2005

Wireless LAN was developed by alternative of LAN and because establishment was easy, have used into special field and special expenditure. Recently, Standard and a technology developed by leaps and bounds. Present is used into purpose of the Building to Building or wide connection etc. and relay of the high speed Internet and usage of picture communication that require multimedia band width. Specially, campus wireless LAM is thought that must secure radius $100\;\~\;200\;m$ dimension at the minimum 10Mbps speed as Internet transit trunk. But, there is difference as degressive here. In this paper, wireless LAN measured for effectiveness proof as Internet transit trunk in actuality utilization environment. Proved that should compose IEEE802.11b as AP more than minimum 3 when compose network to base as measuring result. Hereafter, there is the purpose that achieve performance evaluation of wireless UM in marine environment.

• The KIPS Transactions:PartA
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• v.12A no.5 s.95
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• pp.355-364
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• 2005

With fast advances in computing power and network technologies, online streaming services of continuous media (CM) have been popularly implemented on the Web. To implement such services, a variety of CM streams need to be processed efficiently, so that the Sweep scheme was proposed. This scheme has several advantages such as hiccup-free playbacks and seek-time optimization. In this scheme, however, the entire CM streams are scheduled with a single scheduling period, called a cycle. Since only one scheduling period is allowed in this scheme, a significant amount of disk time is usually wasted because of its inflexible disk schedules. To solve this, we propose a new dynamic Sweep scheme. For this, we devise an algorithm that is able to expand scheduling periods of serviced CM streams and propose a new admission control mechanism guaranteeing hiccup-free playbacks. To show performance gains, we execute various simulation experiments. From the experimental results, we can see that the proposed scheme outperforms the Sweep scheme in terms of disk utilization and scheduling flexibility.

• The Journal of the Korea Contents Association
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• v.11 no.11
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• pp.514-520
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• 2011

Technological development, a diverse range of media adapting to new technology has been developing. Augmented Reality Technology provides realistic information through the stereoscopic 3D images and it has been riding a wave of learner interest as an educational media which can broaden their learning experience through direct operating activity. The biggest reason why the Augmented Reality has gained such attention is because of its unique way of suggesting learning information that unlike the existing educational media, the Augmented Reality provides additional digitalized information while its users are looking at the actual object. Based on the domestic and foreign cases of development for educational contents using the Augmented Reality Technology, this thesis suggests the utilization of Pop-up books and multi-augmented Digilog Books that are ways to maximize the educational effects of the Augmented Reality. Through the development of smartphone applications that are propagating lately at a rapid rate, users can now use the Augmented Reality educational contents in a way that is easier than ever.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.21 no.6
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• pp.1490-1500
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• 1996

One of the important issues for multimedia communications over ATM netowrks is efficient use of net-work resources since transmitting video at low cost requires high utilization of channel bandwidth. In this paper, we propose an effective bandwidth estimation scheme for MPEG sources in ATM networks. It has been known difficult to allocate effective transmission bandwidth to MPEG sources due to its bursty charactersitics. The MPEG traffic stream can bemodeled using five traffic parameters:service rate, burst load ratio, interburst load ratio, burst period, and interburst period. Using these parameters, a transmission bandwidth for each source can be estimated, and the estimated bandwidth is applied synchronously to reduce the queue size in a buffer. For a simple network modelof a high speed link that multiplexes a number of virtual-circuit connections, simulations on adaptive bandwidth allocation were performed, and the results show that the queueing delay is significantly reduced, when compared to a fixed bandwidth allocation.

• Journal of Digital Convergence
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• v.13 no.3
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• pp.193-199
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• 2015

PUSH technology is a technology that can transfer server information without user's request and it is very useful in various areas along with mobile applications. This paper suggest a suitable application model that can utilizes the PUSH technology and mobile devices by finding a useful area. For this, AdMan, a mobile application which can utilize the PUSH technology and mobile devices has been developed. AdMan is a mobile application that developed once and can be able to run on both Android and iOS based mobile devices, since it was developed by using a tool called m-Bizmaker. AdMan is a customer management and advertisement system that can bring big efficiency by utilizing the PUSH technology and mobile application under the today's mobile environment, and it is a good model of ICT technology application of modern society. As an application that can maximize the utilization of the PUSH technology and mobile devices, AdMan can realize better effectiveness if it run on a PUSH server.

• Journal of Digital Convergence
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• v.14 no.12
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• pp.225-230
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• 2016

Dam is built to supply water necessary for life stably and reduce the damage caused by heavy rains. Recently there has been required the analysis and utilization of spatial information on the area around the dam because construction of the dam gives a great impact on the environment of the surrounding area. In this study, we build spatial information about the submerged district due to dam construction using drone and propose the effective method for analysis of the spatial information. As a result, orthoimage and DSM of study area were constructed effectively. Change of submerged district of this area was calculated according to the analysis of spatial information. Building and analyzing spatial information carried out in this study are expected to be utilized as the basis in related fields.