• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.10
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• pp.2256-2262
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• 2015

Recently, device-to-device (D2D) communication has been considered as key technology for future cellular system, because it can solve the problem of excessive data traffic increment and can also provide new communication services. Herein, we propose new neighbor discovery for D2D communication and examine its performance. Our proposed scheme is proximity beacon based discovery in which wireless resource for pilot transmission is assigned based on the spatial correlation of wireless channel and sensing period is adjusted according to target accuracy such that power consumption can be reduced. The performance of our propose scheme is analyzed mathematically and verified through computer simulations.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2007.10a
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• pp.871-874
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• 2007

Stream data need a efficient data management with high reliability and real time processing. The characteristics of these data are a large volume, a short report interval and asynchronous report time. The typical queries of these systems consist of the current query to search the latest signal value, the snapshot query to search the signal value of a past time, the historical query to search the signal value of a past time to current. This paper proposes the efficient method to manage the above signals by using a file structured database in QNX operating systems. The query model to accommodate various query for stream data is proposed. The proposed methods are applied to reactive protection system to verify their usefulness. The COM(Cabinet Operator Module) based on the QNX employs file database that adopts a delta version and a buffering method for the resource limit of a small storage and a low computing power.

• Journal of the Korean Society of Costume
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• v.62 no.7
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• pp.133-149
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• 2012

Jikji, Memory of the World of UNESCO, the world's oldest extant movable metal print book, is a cultural heritage to give motivation for IT power of Korea. Although the cultural value of Jikji is understood in Korea, the value of cultural assets is not satisfactory and the commercialization is not sufficient. Furthermore, most Jikji product designs on the market are simple and limited mainly for the old generation. The purpose of this study is to design fashion-cultural products suitable for young people who will be responsible for this cultural inheritance. The methods of this study were to make the design development through literature research and a case study for Jikji products on the market. For developing the products suitable for young people, 308 university students in Chungju were surveyed. To express end products, computer graphic program, Illustrator CS5, was used. The results of this study showed that the products on the market were not targeted for use by young people. The younger generations want modern and interesting design. Among the 8 design motives that are planned for design development, the most preferred motive numbers, 3, 7, and 8, were used. Design items, such as scarf, wallet and t-shirts, were selected by the result of survey and 3 scarves, 4 wallets, 3 t-shirts, a total of 30 items were developed. The designed products in this study can inform the cultural resource of Korea and contribute to raise the cultural value if they are commercialized.

• Korean Journal of Construction Engineering and Management
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• v.6 no.2 s.24
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• pp.102-110
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• 2005

After the IMF bailout, the Environment of Domestic Construction Industry had changed dramatically. Before the IMF, Domestic Construction Firms are secured by the government regulations and some traditional practices. However, due to the following reasons: a decrease in public works, an increase in uncertainty of market prediction, the change of bid system, and increase in construction firms, recently the competition among construction firms has became keen. Under the serious competition, in order that medium-size construction firms survive in the construction market, it is need to establish the strategy that could increase productivity. In order to establish the strategy, firstly, construction firms should set up an appraisal standard of construction firms. Consequently, This study will introduce companies' objective appraisal in domestic construction market as well as basal data for setting-up strategy through adaptation industry structure analysis of business administration for strategic group analysis and a company which has lagged behind competitive power among the competitive companies can choose a target strategic group which should be pursued it in the future through being classified according to a group taken analogical strategy.

• Journal of Communications and Networks
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• v.5 no.3
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• pp.266-274
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• 2003

One of the major issues in current on-demand routing protocols for ad hoc networks is the high resource consumed by route discovery traffic. In these protocols, flooding is typically used by the source to broadcast a route request (RREQ) packet in search of a route to the destination. Such network-wide flooding potentially disturbs many nodes unnecessarily by querying more nodes than is actually necessary, leading to rapid exhaustion of valuable network resources such as wireless bandwidth and battery power. In this paper, a simple optimization technique for efficient route discovery is proposed. The technique proposed herein is location-based and can be used in conjunction with the existing Location-Aided Routing (LAR) scheme to further reduce the route discovery overhead. A unique feature of our technique not found in LAR and most other protocols is the selective use of unicast instead of broadcast for route request/query transmission made possible by a novel reuse of routing and location information. We refer to this new optimization as the UNIQUE (UNIcast QUEry) technique. This paper studies the efficacy of UNIQUE by applying it to the route discovery of the Dynamic Source Routing (DSR) protocol. In addition, a comparative study is made with a DSR protocol optimized with only LAR. The results show that UNIQUE could further reduce the overall routing overhead by as much as 58% under highly mobile conditions. With less congestion caused by routing traffic, the data packet delivery performance also improves in terms of end-to-end delay and the number of data packets successfully delivered to their destinations.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.41 no.5
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• pp.565-573
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• 2016

Wi-Fi Direct standard technology(Wi-Fi Peer to Peer Technical Specifications v1.2, 2010) was designed for allowing peer to peer communication between two or more devices and various products which have been currently manufactured such as smart phone and smart TV have already provided this technical function. In this technology the role of Coordinator in Wi-Fi infrastructure would be matched to GO(Group Owner) which needs relatively high energy resource and computation power due to the high probability for allowing 3rd-party connection, however, the current standard specification would be limited in terms of energy distribution because it has not included a process to determine the role of GO. To address above problem, this paper classified considerable parameters into the general parameters for the physicality of devices and the specific parameters for considering the role position depending on use-case scenario, and proposed a new method called DIVA to help efficiently determining GO role from the member devices of Wi-Fi Direct network. Furthermore the effect of this mechanism was proved via simulation-based experiments.

• Journal of Korean Society of Water and Wastewater
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• v.29 no.1
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• pp.89-96
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• 2015

Smart water grid is a water network with communication to save water and energy using various water resources. In smart water grid, water product from the various sources can be blended to be supplied to end-users. The product water blending was reported by literatures while feed water blending has been rarely reported so far. In this work, a commercial reverse osmosis (RO) system design software provided by a membrane manufacturer was used to elucidate the effect of feed water blending on the performance of seawater reverse osmosis (SWRO) plant. Fresh water from exisiting water resource was assumed to be blended to seawater to decrease salt concentration of the RO feed water. The feed water blending can simplify the RO system from double to single pass and decrease seawater intake amount, the unit prices of the RO system components including high pressure pump, and operation risk. Due to the increase in RO plant capacity with the feed water blending, however, the RO membrane area and total power consumption increase at higher water blending rates. Therefore, a specific benefit-cost analysis should be carried out to apply the feed water blending to SWRO plants.

• Health Policy and Management
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• v.19 no.1
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• pp.1-30
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• 2009

Korean medical fee contract system between the insurer and healthproviders was introduced in 2000. However, a continuous discord among contracting parties concerned and an irrational operation of an arbitration committee of Ministry for Health, Welfare and Family Affairs (MIHWAF) have made it difficult for them to reach to an agreement over last 8 years. The purpose of this study is to observe the current problems of contract system from the view of health insurance law and actual examples. Furthermore, I examined the of breakdown of negotiation by analyzing the eligibility of contracting parties, rationality of Resource Based Relative Value System (RBRVS) and contracting method and fairness of arbitration method in case of negotiation rupture. The results were as follows: First, since the introduction of medical fee contract system, there has been a problem in that both the president of National Health Insurance Corporation (NHIC) and health care provider association have not held strong negotiation power. Second, the frequent changes and notifications of Relative Value Units (RVUs) without any mutual consent between the insurer and provider association negatively have influenced the conversion factors and finally hindered the agreement of contract. Third, a current process that the conversion factors are mediated and determined at the arbitration committee of MIHWAF in the case of contract breakdown between contracting parties has some flaw in that the irrational composition of committee provoked the lack of fairness and objectivity of mediation. Fourth, we can not prospect a satisfactory outcome of arbitration committee because the mediation always has failed to proceed smoothly due to boycott of both committee members from insurer and providers over last 8 years. As a result, we have to make an every effort to resolve problems mentioned above and then dream of an advanced national health insurance system.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.5 no.10
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• pp.1698-1711
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• 2011

Knowledge is often represented as a set of rules or a semantic network in intelligent systems. Recently, ontology has been widely used to represent semantic knowledge, because it organizes thesaurus and hierarchal information between concepts in a particular domain. However, it is not easy to collect semantic relationships among concepts. Much time and expense are incurred in ontology construction. Collective intelligence can be a good alternative approach to solve these problems. In this paper, we propose a collective intelligence approach of Games With A Purpose (GWAP) to collect various semantic resources, such as words and word-senses. We detail how to construct the semantic information model or ontology from the collected semantic resources, constructing a system named FunWords. FunWords is a Korean lexical-based semantic resource collection tool. Experiments demonstrated the resources were grouped as common nouns, abstract nouns, adjective and neologism. Finally, we analyzed their characteristics, acquiring the semantic relationships noted above. Common nouns, with structural semantic relationships, such as hypernym and hyponym, are highlighted. Abstract nouns, with descriptive and characteristic semantic relationships, such as synonym and antonym are underlined. Adjectives, with such semantic relationships, as description and status, illustration - for example, color and sound - are expressed more. Last, neologism, with the semantic relationships, such as description and characteristics, are emphasized. Weighting the semantic relationships with these characteristics can help reduce time and cost, because it need not consider unnecessary or slightly related factors. This can improve the expressive power, such as readability, concentrating on the weighted characteristics. Our proposal to collect semantic resources from the collective intelligence approach of GWAP (our FunWords) and to weight their semantic relationship can help construct the semantic information model or ontology would be a more effective and expressive alternative.

• Journal of Korea Spatial Information System Society
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• v.12 no.1
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• pp.10-17
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• 2010

Sensor nodes used in Geosensor network are resource limited and power constrained. So it is necessary to research on routing protocols to gather data by using energy efficiently. Wireless sensor networks collect data gathered from sensor nodes by transfering it to the sink using multihop. However, it has two problems. First, the existing works require unnecessary data transmission for choosing a proper parent node to transfer data. Secondly, they have a large number of data transmission because each sensor node has a different path. To solves the problems, we, in this paper, propose a designated path based data aggregation scheme for efficient energy management in WSNs. The proposed scheme can reduce unnecessary data transmission by pre-determining a set of paths and can enable all the sensor nodes to participate in gathering data by running them in round-robin fashion. We show from performance analysis that the proposed scheme is more energy efficient than the existing directed diffusion(DD) and the hierarchical data aggregation(HDA).