• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.11 no.4
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• pp.9-16
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• 2011

This paper represents an interworking architecture for keeping the VLC audio quality between Worldwide Interoperability for Microwave Access (WiMAX) and IEEE 802.11 Mobile Ad hoc Network (MANET) where both mobile routers and mobile nodes are moving dynamically. Systematic performance analysis on the interworking architecture has been conducted by using OPNET simulator to show the results such as Packet Delivery Ratio (PDR) and throughput. Based on simulation results, when the number of MANET nodes is small, PDR remains relatively stable even though data packets increase. However, with the many MANET nodes, PDR decreases as data traffic increases. Throughput is affected by the number of MANET nodes. Especially when the MANET node density has increased further, throughput is much higher, but it is not affected by the mobility speed. However, FTP download and upload response time is not affected much by both the number of MANET nodes and the mobility speed.

• Journal of Fashion Business
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• v.15 no.6
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• pp.1-22
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• 2011

This paper is a study on the information required for developing Korean clothing products intended for Chinese students in Korea and for opening markets of Korean clothing and brands in China. It analyses the buying behaviors, purchasing ability, the favourite apparel type for clothing, and satisfaction with Korean clothing and brands of Chinese students in Korea, with which it seeks a program for South Korea branding to enter into the Chinese clothing market. Three hundred fifty seven students of Hannam University and PaiChai University Chung nam National University in Daejeon-city took part in this study. This paper adopts Descriptive Analysis, Crossing Analysis, Bivariate Correlations, and One-way ANOVA in SPSS 17.0 with Post Hoc Multiple Comparisons to know about the impact of demographic variables of Chinese students in Korea on buying information sources, the criteria for store selection, buying capacity, praise degree on various properties of Korean clothes products and their satisfaction with Korean clothes products. The first proposal of expanding China market for Korean merchants is to achieve maximum sales based on sales promotion strategies, such as the credit card corporations, the store display and sales person service development, SPA, design size development, and to upgrade consumption values. The second proposal is Korean clothes corporations should open the Internet shopping corresponding to the physical stores, the most frequently used information source of Chinese students is the network, from the age distribution of Internet users in 2008 in China, population above 10 and below 30 accounts for 66.7% of all users, In recommending clothes made in Korea to Chinese young people, on-line advertising will get better effects than other strategies, specially during advertisement, they should take good use of Korean television shows and variety shows or help Chinese poor areas to do the social contribution hereby to improve the public image of Korean clothes corporations, which can bring good sale promotion effects as well.

• Strategy21
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• s.37
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• pp.144-176
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• 2015

In September 2013, President Park Geun-hye announced her controversial "Look North" policy, of which the most salient aspect is the "Eurasia Initiative". This comprises various proposals designed to overcome existing constraints by developing new markets and creating new economic partners in continental areas from which South Korea has been alienated since the end of World War II, and this dovetails nicely with China's One Belt, One Road Initiative. The concepts of the "Silk Road Rail Express (SRX)" and the "East Sea Rim Maritime Community (ESRMC)" have also been discussed. SRX is at present a purely symbolic railroad project intended to encourage individual, cultural, trade and diplomatic exchanges. ESRMC is a model for establishing an ad hoc community to promote regional economic cooperation around the East Sea. President Park's Eurasia Initiative will provide South Korean investment for the Northeast to complement Russian plans, like the "Northern Energy Road" being built by Gazprom, and Chinese plans, like the Chang-Ji-Tu Development Plan for the North Korean port of Rajin. China's trade, as well as its energy and food supplies, pass through the Strait of Malacca and the Indian Ocean, and are thus vulnerable to interdiction by India or the US. China is therefore trying to reduce its exposure geopolitical risk by establishing a network of corridors between the Belt and the Road to provide alternative paths. The "China-Pakistan Economic Corridor" and the "China-Myanmar Economic Corridor" provide such connections, and South Korea hopes that SRX and ESRMC can become part of a "China-South Korea Economic Corridor". This concept could do much to revitalize the underdeveloped northern provinces of China and Russia's Far East, not to mention North Korea. By linking up the Trans-Siberian Railway, the Trans-China Railway, the Trans-Mongolian Railway and the Trans-Korean Railway all these Asian countries will be connected to one another, and ultimately to Europe. An interim connection between China and South Korea using a rail-ferry has also been proposed.

• KIPS Transactions on Computer and Communication Systems
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• v.5 no.3
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• pp.55-70
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• 2016

The most critical research issue in MANET environment is on supporting reliable communication between various devices. Various Multi-Hop Routing Protocol studies have proceeded. However, some problems you might have found when you use the existing link state routing technique are that it increases Control Message Overhead and it is unstable when node moves in CR circumstance which has transformation of using channel and MIMC circumstance which uses a number of interfaces. This essay offers a technique which is based on On-Demand Hello and the other technique which used Broadcast Interface of optimization as a solution to decrease Control Message Overhead. Also it proposes Quick Route Restoration technique which is utilized by GPS and MPR Selection technique which consider mobility as a solution of stable communication when node moves. Those offered Routing Protocol and OPNET based simulator result will be expected to be an excellent comparison in related research fields.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.5
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• pp.1087-1096
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• 2011

Vehicular Ad Hoc Network(VANET) using wireless network is offering the communications between vehicle and vehicle(V2V) or vehicle and infrastructure(V2I). VANET is being actively researched from industry field and university because of the rapid developments of the industry and vehicular automation. Information, collected from VANET, of velocity, acceleration, condition of road and environments provides various services related with safe drive to the drivers, so security over network is the inevitable factor. For the secure message authentication, a number of authentication proposals have been proposed. Among of them, a scheme, proposed by Jung, applying database search algorithm, Bloom filter, to RAISE scheme, is efficient authentication algorithm in a dense space. However, k-anonymity used for obtaining the accurate vehicular identification in the paper has a weak point. Whenever requesting the righteous identification, all hash value of messages are calculated. For this reason, as the number of car increases, a amount of hash operation increases exponentially. Moreover the paper does not provide a complete key exchange algorithm while the hand-over operation. In this paper, we use a Received Signal Strength Indicator(RSSI) based velocity and distance estimation algorithm to localize the identification and provide the secure and efficient algorithm in which the problem of hand-over algorithm is corrected.

• Journal of Navigation and Port Research
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• v.38 no.4
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• pp.343-348
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• 2014

A routing scheme called MCS-NLTC using a self-configuration marine network model and the diversity and heterogeneity of broadband wireless access technologies is newly proposed. The MCS-NLTC algorithm selects optimal nodes and carriers for every hop in optimal routes based on not conventional hop counts but normalized distances to destination ships (location information of destination ships). Normalized transmission characteristics of applications and carriers are considered to get optimal routes as well. The location information enhances convergence speed to get destinations, which makes the route search time faster. Evaluated performances are compared with those of the schemes based on max-win (OMH-MW), and normalized transmission characteristics (MCS-NTC).

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.4
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• pp.97-107
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• 2013

Underwater wireless communication systems can be useful for underwater environment observation, catastrophe prevention, ocean resources exploration, ocean organism research, vessel sinking exploration, and so on. However, unlike terrestrial wireless communication, underwater wireless communication should consider factors such as long propagation delay, limited transmission capacity, high bit-error rate due to potential loss in power, ambient noise, man-made noise, multi-path, etc., because of the inherent characteristics of water. Thus, in this paper, we propose a suitable media access control(MAC) protocol that applies a combination of the ALOHA MAC protocol and the CSMA/CA MAC protocol to underwater environment. We further propose a mathematical analysis model to evaluate performance. We also verify performance improvement in the proposed scheme in comparison with existing MAC protocols.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.4
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• pp.1624-1647
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• 2020

Vehicular network is one of the most important subjects for researchers in recent years. Anycast routing protocols have many applications in vehicular ad hoc networks. The aim of an anycast protocol is sending packets to at least one of the receivers among candidate receivers. Studies done on anycast protocols over vehicular networks, however, have capability of implementation on some applications; they are partial, and application specific. No need to say that the lack of a comprehensive study, having a strong analytical background, is felt. Mathematical modeling in vehicular networks is difficult because the topology of these networks is dynamic. In this paper, it has been demonstrated that vehicular networks can be modeled based on time-expanded networks. The focus of this article is on geographical anycast. Three different scenarios were proposed including sending geographic anycast packet to exactly-one-destination, to at-least-one-destination, and to K-anycast destination, which can cover important applications of geographical anycast routing protocols. As the proposed model is of MILP type, a decentralized heuristic algorithm was presented. The evaluation process of this study includes the production of numerical results by Branch and Bound algorithm in general algebraic modeling system (GAMS) software and simulation of the proposed protocol in OMNET++ simulator. The comprehension of the result of proposed protocol and model shows that the applicability of this proposed protocol and its reactive conformity with the presented models based on presented metrics.

• Journal of Advanced Navigation Technology
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• v.20 no.3
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• pp.238-245
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• 2016

There are technological, operational and environmental constraints at tactical edge, which are disconnected operation, intermittent connectivity, and limited bandwidth (DIL), size, weight and power (SWaP) limitations, ad-hoc and mobile network, and so on. To overcome these limitations and constraints, we use service-oriented architecture (SOA) based technologies. Moreover, the operation environment is highly dynamic: requirements change in response to the emerging situation, and the availability of resources needs to be updated constantly due to the factors such as technical failures. In order to use appropriate resources at the right time according to the mission, it needs to find the best resources. In this context, we identify ontology-based mission service model including mission, task, service, and resource, and develop capability-based matching in tactical edge environment. The goal of this paper is to propose a capability-based semantic matching for dynamic resource allocation. The contributions of this paper are i) military domain ontologies ii) semantic matching using ontology relationship; and (iii) the capability-based matching for the mission service model.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.1
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• pp.77-88
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• 2010

Wireless Mesh Networks are consist of mobility mesh clients and mesh routers. WMNs can communicate with heterogeneous networks such as IEEE 802.11, IEEE 802.15, IEEE 802.16 and sensor networks. WMNs which is based on ad hoc network are on research and developing to enhance WLANs, WPANs, or WMANs. WMNs can offer environment to serve human, service to person area, campus, and metro. But WMNs has many problems to solve about enhancing performance and generalization. Among them, Existing protocol layers has many problems enhancing to optimize WMNs. This document issues problems about WMNs in protocol layer and suggest the solutions. Also, suggests the requirements and the methods of QoS supporting issue.