• The Journal of Korean Institute of Communications and Information Sciences
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• v.37C no.11
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• pp.1170-1181
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• 2012

Wireless Sensor Networks(WSNs) are used in diverse applications. In general, sensor nodes that are easily deployed on specific areas have many resource constrains such as battery power, memory sizes, MCUs, RFs and so on. Hence, first of all, the efficient energy consumption is strongly required in WSNs. In terms of event states, event-driven deliverly model (i.e. surveillance and reconnaissance applications) has several characteristics. On the basis of such a model, clustering algorithms can be mostly used to manage sensor nodes' energy efficiently owing to the advantages of data aggregations. Since a specific node collects packets from its child nodes in a network topology and aggregates them into one packet to relay them once, amount of transmitted packets to a sink node can be reduced. However, most clustering algorithms have been designed without considering can be reduced. However, most clustering algorithms have been designed without considering characteristics of event-driven deliverly model, which results in some problems. In this paper, we propose enhanced clustering algorithms regarding with both targets' movement and energy efficiency in order for applications of surveillance and reconnaissance. These algorithms form some clusters to contend locally between nodes, which have already detected certain targets, by using a method which called CHEW (Cluster Head Election Window). Therefore, our proposed algorithms enable to reduce not only the cost of cluster maintenance, but also energy consumption. In conclusion, we analyze traces of the clusters' movements according to targets' locations, evaluate the traces' results and we compare our algorithms with others through simulations. Finally, we verify our algorithms use power energy efficiently.

• Journal of Korean Society of Transportation
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• v.21 no.1
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• pp.91-102
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• 2003

There are two goals in this paper. The one is development of existing CA(Cellular Automata) model to explain more realistic deceleration process to stop. The other is the application of the updated CA model to forecasting simulation to predict short term link travel time that takes a key rule in finding the shortest path of route guidance system of ITS. Car following theory of CA models don't makes not response to leading vehicle's velocity but gap or distance between leading vehicles and following vehicles. So a following vehicle running at free flow speed must meet steeply sudden deceleration to avoid back collision within unrealistic braking distance. To tackle above unrealistic deceleration rule, “Slow-to-stop” rule is integrated into NaSch model. For application to interrupted traffic flow, this paper applies “Slow-to-stop” rule to both normal traffic light and random traffic light. And vehicle packet method is used to simulate a large-scale network on the desktop. Generally, time series data analysis methods such as neural network, ARIMA, and Kalman filtering are used for short term link travel time prediction that is crucial to find an optimal dynamic shortest path. But those methods have time-lag problems and are hard to capture traffic flow mechanism such as spill over and spill back etc. To address above problems. the CA model built in this study is used for forecasting simulation to predict short term link travel time in Kangnam district network And it's turned out that short term prediction simulation method generates novel results, taking a crack of time lag problems and considering interrupted traffic flow mechanism.

• Journal of Korea Water Resources Association
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• v.43 no.2
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• pp.131-138
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• 2010

Due to the increased water demand and severe drought as an effect of the global warming, the effluent from wastewater treatment plants becomes considered as an alternative water source to supply agricultural, industrial, and public (gardening) water demand. The effluent from the wastewater treatment plant is a sustainable water source because of its good quality and stable amount of water discharge. In this study, the water reuse system was developed to minimize total construction cost to cope with the uncertain water demand in future using two-stage stochastic linear programming with binary variables. The pipes in the water reuse network were constructed in two stages of which in the first stage, the water demands of users are assumed to be known, while the water demands in the second stage have uncertainty in the predicted value. However, the water reuse system has to be designed now when the future water demands are not known precisely. Therefore, the construction of a pipe parallel with the existing one was allowed to meet the increased water demands in the second stage. As a result, the trade-off of construction costs between a pipe with large diameter and two pipes having small diameters was evaluated and the optimal solution was found. Three scenarios for the future water demand were selected and a hypothetical water reuse network considering the uncertainties was optimized. The results provide the information about the economies of scale in the water reuse network and the long range water supply plan.

• The Journal of the Korea Contents Association
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• v.12 no.7
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• pp.463-472
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• 2012

For last decade, the amount of information has been increased rapidly because of the internet and computing technology development, mobile devices and sensors, and social networks like facebook or twitter. People who want to gain important knowledge from database have been frustrated with large database. Many studies for automatic knowledge extracting meaningful knowledge from large database have been fulfilled. In that sense, automatic knowledge extracting with computing technology has been highly significant in information technology field, but still has many challenges to go further. In order to improve the effectives and efficiency of knowledge extracting system, test collection is strongly necessary. In this research, we introduce a test collection for automatic knwoledge extracting. We name the test collection KEEC/KREC(KISTI Entity Extraction Collection/KISTI Relation Extraction Collection) and present the process and guideline for building as well as the features of. The main feature is to tag by experts to guarantee the quality of collection. The experts read documents and tag entities and relation between entities with a tool for tagging. KEEC/KREC is being used for a research to evaluate system performance and will continue to contribute to next researches.

• Journal of IKEEE
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• v.5 no.1 s.8
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• pp.8-15
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• 2001

This paper remarks IETF based requirements for IP/UDP/RTP header compression issued in 3GPP2 All IP Ad Hoc Meeting and protocol stacks of the next generation mobile station. All IP Network, for real time application such as Voice over IP (VoIP) multimedia services based on 3GPP2 3G cdma2000. Frames for various protocols expected in the All IP network Mobile Station (MS) are explained with several figures including the bit-for-bit notation of header format based on IETF draft of Robust Header Compression Working Group (ROHC). Especially, this paper includes problems of IS-707 Radio Link Protocol (RLP) for header compression which will be expected to modify in All IP network MS's medium access layer to accommodate real time packet data service[1]. And also, since PPP has also many problems in header compression and mobility aspects in MS protocol stacks for 3G cdma2000 packet data network based on Mobile IP (PN-4286)[2], we introduce the problem of solution for header compression of PPP. Finally. we suggest the guidelines for All IP network MS header compression about expected protocol stacks, radio resource efficiency and performance.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.26 no.3
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• pp.679-691
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• 2016

As vehicle started to contain many different communication devices, collecting external information became possible in IoT environment. In such environment, remotely controling vehicle is possible when vehicle information is obtained by looking in to vehicle network through smart device. However, android based smart device applications are vulnerable to malicious modulation and redistribution. Modulated android application can lead to vehicle information disclosure that could bring about vehicle control accident which becomes threat to drivers. furthermore, since vehicles today does not contain security methods to protect it, they are very vulnerable to security threats which can cause serious damage to users and properties. In this paper, many different vehicle management android applications that are sold in Google Play has been analyzed. With this information, possible threats that could happen in vehicle management applications are being analysed to prove the risks. the experiment is done on actual vehicle to prove the risks. Also, access control method to protect the vehicle against malicious actions that could happen through external network in IoT environment is suggested in the paper.

• Journal of the Economic Geographical Society of Korea
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• v.12 no.4
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• pp.388-405
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• 2009

This paper examines the triple helix innovation system in the Oresund food cluster, considered as one of the most competitive food clusters in the globe. The result of the case study represents that the triple helix system of the Oresund food cluster is composed of three layers of triple helix spaces. Such three triple helix spaces play a crucial role in making the industry-university-government relationships interactive and dynamic. First, knowledge spaces in the Oresund food cluster are very strong and competitive in education and R&D capabilities in related to the food sector. 14 universities in the Oresund region are connected and coordinated by the integrated organization body, called the Oresund University. Second, the Oresund Food Network(OFN), as a central consensus space in the Oresund food cluster, functions as a pivotal organization that facilitates and coordinates cooperations between firms and universities. Third, most important innovation space in the triple helix system of Oresund food cluster can be science parks and business incubators such as Ideon Science Park, which contribute to linking, between research and commercialization, and between firms and universities in the region. In a nutshell, the Oresund food cluster has been evolved as an innovative regional cluster on the basis of well-established three-layered triple helix spaces of regional innovation system.

• Proceedings of the Korean Information Science Society Conference
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• 2005.07a
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• pp.829-831
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• 2005

실시간 시스템이란 시간적인 제한을 가지고 작업 수행 결과의 정확도가 보장되는 시스템으로 경성 실시간 시스템과 연성 실시간 시스템으로 분류된다. 최근 분산 실시간 분야에서 새로운 패러다임으로써 폭넓게 활용되기 시작한 실시간 객체 모델인 TMO는 Kane Kim과 Kopetz에 의해 처음 제안되었다. TMO 모델은 경성 또는 연성 실시간 응용과 병렬 컴퓨팅 응용 프로그램에서 사용 될 수 있으며, 시스템의 기능적인 면과 시간 조건 수행 모두를 명확히 정의할 수 있다. TMO의 네트워크로 구성되는 실시간 분산 환경에서의 실행을 위해 몇 개의 TMO 실행 엔진이 개발 되었는데, 그 중에서 LTMOS라는 리눅스 기반의 연성 실시간 미들웨어 엔진이 한국외대 RTDCS lab.에서 개발되었다. 하지만 LTMOS의 실시간 시스템 수행 중 작업량의 과부하로 인한 deadline 위반이나, 시스템간의 분산 IPC 통신에 있어서 Channel Traffic이 빈번한 경우 실시간 시스템을 유지할 수 없다는 문제점들을 갖고 있다. 이러한 문제점들을 해결하고 조금 더 효율적인 실시간 시스템을 유지하기 위해서, TMO 프로그램의 resource 정보를 담고 있는 ODS(Object Data Store)만을 다른 노드에 있는 자신의 TMO 프로그램 Replica로 이주해서 실시간 로드 밸런싱을 구현하는 기법을 사용하였다. 이에 본 논문에서는 TMO 프로그램들의 deadline 위반 및 Channel Traffic 부하를 감지할 수 있는 Node Monitor와 최적의 노드를 선별할 수 있는 Migration Manager를 새롭게 추가하였고, 쓰레드들의 스케줄러인 WRMT에 이주 작업을 하기 위한 부가적인 기능을 구현하였다. 2D 이미지의 관측점을 줄여 계산량을 대폭 감소시키는 장점을 갖는다.것으로 조사되었으며 40대 이상의 연령층은 점심비용으로 더 많은 지출을 하고 있는 것으로 나타났다. 4) 끼니별 한식에 대한 선호도는 아침식사의 경우가 가장 높았으며, 이는 40대와 50대에서 높게 나타났다. 점심 식사로 가장 선호되는 음식은 중식, 일식이었으며 저녁 식사에서 가장 선호되는 메뉴는 전 연령층에서 일식, 분식류 이었으며, 한식에 대한 선택 정도는 전 연령층에서 매우 낮게 나타났다. 5) 각 연령층에서 선호하는 한식에 대한 조사에서는 된장찌개가 전 연령층에서 가장 높은 선호도를 나타내었고, 김치는 40대 이상의 선호도가 30대보다 높게 나타났으며, 흥미롭게도 30세 이하의 선호도는 30대보다 높게 나타났다. 그 외에도 떡과 죽에 대한 선호도는 전 연령층에서 낮게 조사되었다. 장아찌류의 선호도는 전 연령대에서 낮았으며 특히 30세 이하에서 매우 낮게 조사되었다. 한식의 맛에 대한 만족도 조사에서는 연령이 올라갈수록 한식의 맛에 대한 만족도는 낮아지고 있었으나, 한식의 맛에 대한 만족도가 높을수록 양과 가격에 대한 만족도는 높은 경향을 나타내었다. 전반적으로 한식에 대한 선호도는 식사 때와 식사 목적에 따라 연령대 별로 다르게 나타나고 있으나, 선호도는 성별이나 세대에 관계없이 폭 넓은 선호도를 반영하고 있으며, 이는 대학생들을 대상으로 하는 연구 등에서도 나타난바 같다. 주 5일 근무제의 확산과 초 중 고생들의 토요일 휴무와 더불어 여행과 엔터테인먼트산업은 더욱 더 발전을 거듭하고 있으며, 외식은 여행과 여가 활동의 필수적인 요소로써 그 역할을 일조하고 있다. 이와 같은 여가시간의 증가는 독신자들에게는 좀더 많은 여유시간을 가족을

• Journal of the Korean association of regional geographers
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• v.20 no.3
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• pp.256-258
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• 2014

This paper aims at examining the role of university, industry and government, which constitute the triple-helix innovation system in hi-tech cluster, based on the case of the Research Triangle Park, North Carolina, USA. Firstly, the state government has played a catalytic role by building the horizontal governance of triple-helix actors. By doing so, the state government has made it possible for not only growing but also transforming the RTP as an high-tech cluster. Secondly, universities in the triangle area have played to some extent a limited role in sustaining the evolution of cluster. Thirdly, the RTP has long been dominated by a small group of large firms. However, the situation has been changed since 1990s, because new start-ups from universities and local large firms and the technology transfer activities between universities and firms have been increased in the RTP and its surrounding area. Finally, it argues that the continuous evolution of the RTP has been to some or large extent influenced by the transition from the exogenous development model to the endogenous development model.

• Proceedings of the Korea Contents Association Conference
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• 2008.05a
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• pp.819-822
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• 2008

As the IT and computer network technology is developed very rapidly, the quantity of digital contents is increased and disseminated more widely. The digital contents is generally expressed in 2 or 3 dimensional multimedia format and the visible human image that is taken from human body is very important because of its variety of usefulness. The KISTI(Korea Institute of Science and Technology Information) is now constructing various Korean human informations such as visible Korean, digital Korean, human bone property and human models. These informations are accessable through the internet. However, these human images are not easily understandable for general users because they are specialized in medical image field and there is no detailed explanation data. In this study, we designed the annotation database and searching interface for KISTI's visible Korean database. This annotation database involved the detailed explanation and special note of visible Korean data and it can connect the image and text data of visible Korean with each other. By studying this database and interface design, the KISTI's visible Korean database is more easily accessable and understandable to general users and it can promote the usage of visible Korean data more widely.