• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.25 no.8A
• /
• pp.1169-1176
• /
• 2000

In this paper, label assignment schemes considering the IP flow model for the efficient MPLS traffic engineering are proposed and evaluated. Based on the IP flow model, the IP flows are classified into transient flows and base flows. Base flows, which last for a long time, transmit data in high bit rate, and be composed of many packets, have good implications for the MPLS traffic engineering, because they usually cause network congestion. To make use of base flows for the MPLS traffic engineering, we propose two base flow classifiers and label assignment schemes where transient flows are allocated to the default LSPs and base flows to explicit LSPs. Proposed schemes are based on the traffic-driven label triggering method combined with a routing tabel. The first base flow classifier uses both flow size in packet counts and routing entries, and the other one, extending the dynamic X/Y flow classifier, is based on a cut-through ratio. Proposed schemes are shown to minimize the number of labels, not degrading the total cut-through ratio.

• Journal of Internet Computing and Services
• /
• v.6 no.6
• /
• pp.107-115
• /
• 2005

A workflow procedure has recently become more complicated and large scaled. In this paper, we propose an advanced workflow modeling methodology, called a fragment driven cooperative workflow modeling methodology. which enables several real workflow designers to cooperatively define a workflow model. The methodology is a Bottom-Up approach in terms of integrating a set of fragment ICNs to compose a complete workflow model. Each fragment ICN is defined by each participant in the cooperative modeling session, We also use the ICN based formal description and the ICN based graphical notation as well. Finally, we prove the feasibility of the methodology by implementing a cooperative workflow modeling system.

• Journal of Korean Society of Coastal and Ocean Engineers
• /
• v.25 no.3
• /
• pp.123-127
• /
• 2013

In this study, the buckling behaviors during the installation of a bucket foundation for an offshore wind turbine tower were investigated. The objective structure was modeled by using a commercial structural analysis program, and the buckling behavior of the model was estimated as Batdorf's parameter Z in the design code. The surrounding soil conditions and loading condition were applied to the verified analysis model. The effects of parameters such as the longitudinal stiffeners and driven depth were estimated for the buckling capacity. As a result, it was found that the longitudinal stiffeners could drastically increase the buckling capacity in a specific region. In addition, the buckling capacities increased linearly when considering the effect of the surrounding soil.

• Journal of the Korean Society for information Management
• /
• v.31 no.1
• /
• pp.231-250
• /
• 2014

Due to the recent development of Information and Communication Technologies (ICT), the amount of research publications has increased exponentially. In response to this rapid growth, the demand of automated text processing methods has risen to deal with massive amount of text data. Biomedical text mining discovering hidden biological meanings and treatments from biomedical literatures becomes a pivotal methodology and it helps medical disciplines reduce the time and cost. Many researchers have conducted literature-based discovery studies to generate new hypotheses. However, existing approaches either require intensive manual process of during the procedures or a semi-automatic procedure to find and select biomedical entities. In addition, they had limitations of showing one dimension that is, the cause-and-effect relationship between two concepts. Thus;this study proposed a novel approach to discover various relationships among source and target concepts and their intermediate concepts by expanding intermediate concepts to multi-levels. This study provided distinct perspectives for literature-based discovery by not only discovering the meaningful relationship among concepts in biomedical literature through graph-based path interference but also being able to generate feasible new hypotheses.

• Journal of Agricultural Extension & Community Development
• /
• v.21 no.2
• /
• pp.211-254
• /
• 2014

Malawi's agricultural extension system has been subjected to a number of criticisms in recent times for failing to contribute significantly to agricultural development and for not responding to the needs of the smallholder farmers. Despite this, extension is still seen as key to improving poverty and rural livelihoods.There is a number of challenges facing extension that require a response from the public sector and other stakeholders. A clear and positive response to these challenges will help shape the future of agricultural extension in Malawi for the benefit of all farmers and the attainment of the broad policy objectives of government: democratization, market liberalization, decentralization, HIV/AIDS crisis, shrinking public sector resources, public sector reform, and co-ordination, etc. The mission is to provide pluralistic demand driven extensions services and promote equalisation and co-ordination in service provision in order to achieve food security at household level, there-by reducing poverty. On the other hand the vision is that 'All farmers' demand and access high quality extension services from those best able to provide them'. DAES implements its extension policy through the District Agricultural Extension Services System (DAESS), based on Model Village Approach.

• Atmosphere
• /
• v.25 no.1
• /
• pp.85-97
• /
• 2015

This study is to investigate future changes in carbon cycle using the HadGEM2-Carbon Cycle simulations driven by $CO_2$ emissions. For experiment, global carbon budget is integrated from the two (8.5/2.6) representative concentration pathways (RCPs) for the period of 1860~2100 by Hadley Centre Global Environmental Model, version 2, Carbon Cycle (Had-GEM2-CC). From 1985 to 2005, total cumulative $CO_2$ amount of anthropogenic emission prescribed as 156 GtC. The amount matches to the observed estimates (CDIAC) over the same period (136 GtC). As $CO_2$ emissions into the atmosphere increase, the similar increasing tendency is found in the simulated atmospheric $CO_2$ concentration and temperature. Atmospheric $CO_2$ concentration in the simulation is projected to be 430 ppm for RCP 2.6 at the end of the twenty-first century and as high as 931 ppm for RCP 8.5. Simulated global mean temperature is expected to rise by $1.6^{\circ}C$ and $3.5^{\circ}C$ for RCP 2.6 and 8.5, respectively. Land and ocean carbon uptakes also increase in proportion to the $CO_2$ emissions of RCPs. The fractions of the amount of $CO_2$ stored in atmosphere, land, and ocean are different in RCP 8.5 and 2.6. Further study is needed for reducing the simulation uncertainty based on multiple model simulations.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.33 no.9
• /
• pp.688-698
• /
• 2009

Using the multi-dimensional, multi-phase, nonisothermal Polymer Electrolyte Fuel Cell (PEFC) model presented in Part I, the effects of land/channel flow-field on temperature and liquid saturation distributions inside PEFCs are investigated in Part II. The focus is placed on exploring the coupled water transport and heat transfer phenomena within the nonisothermal and two-phase zone existing in the diffusion media (DM) of PEFCs. Numerical simulations are performed varying the land and channel widths and simulation results reveal that the water profile and temperature rise inside PEFCs are considerably altered by changing the land and channel widths, which indicates that oxygen supply and heat removal from the channel to the land regions and liquid water removal from the land toward the gas channels are key factors in determining the water and temperature distributions inside PEFCs. In addition, the adverse liquid saturation gradient along the thru-plane direction is predicted near the land regions by the numerical model, which is due to the vapor-phase diffusion driven by the temperature gradient in the nonisothermal two-phase DM where water evaporates at the hotter catalyst layer, diffuses as a vapor form and then condenses on the cooler land region. Therefore, the vapor phase diffusion exacerbates DM flooding near the land region, while it alleviates DM flooding near the gas channel.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.39 no.3
• /
• pp.275-282
• /
• 2015

Recently, Vecna BEAR type robot to save injured individuals from inaccessible areas has been developed to minimize the loss of life. Because this robot is driven on rough terrain, there is a risk of rollover and vibration, which could impact the injured. In order to guarantee its stability, an algorithm is required that can estimate the speed limits for various environments in real time. Therefore, a dynamic model for real-time analysis is needed for this algorithm. Because the tracks used as the driving component of Vecna BEAR type robot consist of many parts, it is impossible to analyze the multibody tracks in real time. Thus, a lumped track model that satisfies the requirements of a short computation time and adequate accuracy is required. This study performed lumped track modeling, and the traction force was verified using RecurDyn, which is a dynamic commercial program.

• Journal of Information Technology Services
• /
• v.10 no.4
• /
• pp.171-189
• /
• 2011

KAs information and knowledge are increasingly becoming more important in the knowledge-driven society, knowledge management, as a very important management paradigm, is securing firm position in private and public sectors. Complying with this paradigm, government-funded research institutes in science-technology sector are actively utilizing knowledge management by employing knowledge management system and evaluating its applications' performance. The purpose of this study is to develop evaluation items and measurement indices to rationally measure knowledge management performance of the government-funded research institutes and to verify the feasibility of applying these evaluation items and indices. To achieve this research goal, the evaluation model of knowledge management performance was constructed by reviewing and integrating the existing studies, and subsequently, evaluation areas, evaluation items, measurement indices were derived from this evaluation model. Also, the feasibility analysis on the evaluation items and measurement indices was performed by means of FGI(Focus Group Interview) with the knowledge management experts belonging to Korean government-funded institutions in science-technology sector. The implications of this study are as follows : in theoretical perspective, this study has proposed a criterion frame to evaluate knowledge management performance, and has rationally drawn evaluation items and measurement indices from the criterion frame. And in practical perspective, this study has improved the validity and practicality of the measurement indices, which can lead to more reasonable and easier evaluation of knowledge management performance of the government-funded research institutes.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.10 no.2
• /
• pp.256-263
• /
• 2009

KORAIL carries out an improvement project of railway signaling system for the conventional line from the existing method which permits a train to move within limited speed the ground signal of ATS(Automatic Train Stop) system. The proposed system makes possible that a train can be driven using a speed profile created by onboard signaling system(ATP) with the movement authority from ground balise. A driving test over 100,000km is being executed by developing a tilting train for the speed elevation on the conventional line. And, the introduction of the tilting train by ATP system to the Jung-ang line is expected. However, a speed elevation on a curved line section has a restriction. Therefore, research on safety braking model and train separation control technology for the localization of ATP system is required preferentially. In this paper, we presented a safety braking model of ATP system and a train separation control method that use ground balise as variable information provider, and executed a performance simulation.