• Proceedings of the IEEK Conference
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• 2003.11c
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• pp.227-230
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• 2003

Mobile SCTP (mSCTP) is a new scheme which can be used to provide seamless handover for the mobile node. The reason that is possible is because of the SCTP extension which provides a method to reconfigure IP address on an existing SCTP association (ADDIP). While mSCTP focuses on an association originated ken mobile node (MN) toward fixed correspondent node (CN), mSCTP with Mobile IP support an association originated from CN toward MN by using the Home Agent in Mobile IP and location management. However, there are still some problems related to communication interruption. In this paper, we present a new scheme to solve these problems. The main idea of this scheme is using the home address of MN as a backup path of an SCTP association.

• Bulletin of the Society of Naval Architects of Korea
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• v.21 no.2
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• pp.35-42
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• 1984

A line integral is exhibited which has the same value for all paths surrounding the tip of crack in a two dimensional strain field of elastic-plasticc material. Finite element method was used to determine Rice's J-integral value in centrally cracked plate. These numerical J-integral values were compared with corresponding values of reference with low hardening and high yield strength. The J-integral value was also computed for a crack extension and different load condition. For increasing crack length the value of J-integral also increases, this means that the crack is unstable. To prove path independent, three paths were used in the analysis and proved.

• Journal of Families and Better Life
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• v.15 no.4
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• pp.41-54
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• 1997

The purpose of this study is to analyze information search according to consumer's prior knowledge and degree of importance of products. Questionnare survey method was used in this research. The sample was taken from 548 university students in Seoul from 19th of June to 26th of June in 1997. Statistical methods used in this study were Frequency, Percentage, Regression and path Analysis. The major findings are summarized as follows; 1) The level of Consumer's prior knowledge showed somewhat middle. 2) Degree of importance of products showed in order of quality, A/S extension exchange price reliance of a manufacturing company a design etc. 3) Information search for the consumer's prior knowledge and importance showed high on the whole. The more prior knowledge consumer have the better they recognize for the importance of products. Therefore consumers are more likely to search information.

• Journal of Korean Society of Transportation
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• v.28 no.2
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• pp.7-19
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• 2010

Users of metropolitan railroad is increased continuously because of its various advantage such as comfortableness, convenience and punctuality. Thus, several local government including Seoul considered new installation or extension of railroads and four railroad operators maintain seventeen lines at present. After public transportation reforms in 2004 and integrated discount fare system in 2007, public transportation become more convenient in many aspects. However, these trials gives much more complex allocating problems of revenues among public transportation operators. In this paper, we deal with revenue allocating problems among public transportation operators after integrated discount fare system in 2007. Specifically, this study focuses on allocating revenues to metropolitan railroad operators by using RF card data. This research roughly proposes the methodology of O/D extraction from RF card data, generalized cost estimation and allocating revenue algorithm. We use RF card data in order to draw out exact individual O/D data and try to compare our results with those of Korea Smart Card Company. In generalized cost estimation, survey study about transfer factors is conducted for accurate estimation of generalized cost function. Lastly, new allocating revenue algorithm using k-path and non-dominated path concept is suggested. It is expected that case study is also performed with real revenues and O/D data in order to check up the application. Preposed methodology in this research can contribute to solve present and future revenue allocating issues according to the introduction of LRT and private railroad.

• The Journal of the Korea Contents Association
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• v.13 no.10
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• pp.523-532
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• 2013

When the golf club hits the ground prior to making contact with the golf ball, we define it as 'fat shot'. The aim of this research was to investigate the difference between normal shot and fat shot in golf. Five candidates playing as recreational golfer participated in this research and they were all right-handed people. Time phase between each event, wrist cocking angle, elbow extension-flexion angle, backswing height, pelvis angle, thorax angle, L-GRF, R-GRF, pelvis linear velocity, pelvis angular velocity and COG path were calculated. For statistical analysis the paired T-test was used. An early un-cocking, an early right elbow extension and impact with leaving their weight behind foot were not reasons of fat shot. Backswing height, X-Factor, pelvis angle and thorax rotation angle were not different between normal shot and fat shot. But we could find a pattern of abrupt pelvic movement and weight shift to target direction just before impact in case of fat shot. In addition fat shot showed time-delayed and small value of pelvis linear velocity pattern to upward during downswing phase as against normal shot.

• Journal of Agricultural Extension & Community Development
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• v.27 no.3
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• pp.111-124
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• 2020

This study begins with an interest in community capacity, the basis for mobilizing community action and the driving force of community development. The study aims to identify the structural equation model of community capacity, social participation, satisfaction in life, and the impact relationship and to verify the differences between urban and rural areas. The analysis data used the 2018Korean Social Integration Survey, which is the statistical data for national approval. The analysis method was performed by using SPSS was used to perform descriptive analysis and t-test, and the structural equation model. Multi-group analysis of AMOS was also performed to verify the research model. As the result of analysis, both the condition and status of community capacity and social participation, which are products of community capacity, showed a higher average of rural areas than urban areas. As a result of the analysis of the structural equation model between community capacity, social participation, and life satisfaction, differences between rural and urban groups were identified. In rural areas, both the capacity-condition and the capacity-status variables act as positive factors for social participation and life satisfaction, but in urban areas, the path of capacity-condition, social participation, capacity-status and life satisfaction was significant. On the other hand, social participation variables acted as a factor of direct and indirect negatively influence on life satisfaction. Therefore, it can be said that the quality of community capacity in rural areas is superior to that of urban areas.

• Geomechanics and Engineering
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• v.28 no.6
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• pp.613-624
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• 2022

A study of the evolution of overburden fractures under the solid-fluid coupling state was conducted based on the geological and mining characteristics of the coal seam depth, weak strata cementation, and high-intensity mining in the mining areas of West China. These mining characteristics are key to achieving water conservation during mining or establishing groundwater reservoirs in coal mines. Based on the engineering background of the Daliuta Coal Mine, a non-hydrophilic simulation material suitable for simulating the weakly cemented rock masses in this area was developed, and a physical simulation test was carried out using a water-sand gushing test system. The study explored the spatial distribution and dynamic evolution of the fractured zone in the mining overburden under the coupling of stress and seepage. The experimental results show that the mining overburden can be vertically divided into the overall migration zone, the fracture extension zone and the collapse zone; additionally, in the horizontal direction, the mining overburden can be divided into the primary fracture zone, periodic fracture zone, and stop-fracture zone. The scope of groundwater flow in the overburden gradually expands with the mining of coal seams. When a stable water inrush channel is formed, other areas no longer generate new channels, and the unstable water inrush channels gradually close. Finally, the primary fracture area becomes the main water inrush channel for coal mines. The numerical simulation results indicate that the overlying rock breaking above the middle of the mined-out area allows the formation of the water-conducting channel. The water body will flow into the fracture extension zone with the shortest path, resulting in the occurrence of water bursting accidents in the mining face. The experimental research results provide a theoretical basis for the implementation of water conservation mining or the establishment of groundwater reservoirs in western mining areas, and this theoretical basis has considerable application and promotion value.

• Journal of KIISE:Information Networking
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• v.34 no.5
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• pp.328-339
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• 2007

Conventional topology-based routing protocols are not suitable for inter-vehicular communication, where frequent route updates are necessary due to continuous and abrupt changes in network topology Position-based routing protocols are widely accepted to better serve their purpose in such a scenario as they do not require path discovery or maintenance. However they have to deal with the overhead of the location service and inaccurate position information. This paper proposes the MMFP (Multi-hop MAC Forwarding Protocol) for inter-vehicle communication that relies on reachability information collected from received packets in making a forwarding decision without path discovery. The MMFP is designed as an extension to the IEEE 802.11 MAC layer to ensure accuracy in its time-critical operations. This paper also presents some simulation results that demonstrate the superior performance of the MMFP over AODV in a realistic inter-vehicular communication.

• Journal of KIISE:Information Networking
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• v.31 no.6
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• pp.595-607
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• 2004

Networks often evolve to provide a host with multiple access points to the Internet. In this paper, we propose a transport layer load distribution mechanism utilizing the multiple network interfaces simultaneously. We specifically propose an extension of Stream Control Transmission Protoco1 (SCTP) to have load sharing over multiple network interfaces. We named the particular service provided by the Proposed load sharing mechanism to be LS (Load Sharing) mode service. LS mode service is based on the following four key elements: (i) the separation of flow control and congestion control, (ii) congestion window based striping, (iii) redundant packet retransmission for fast packet loss recovery, (iv) a novel mechanism to keep track of the receiver window size with the SACKS even if they arrive out-of-order. Through simulations, it is shown that the proposed LS mode service can aggregate the bandwidth of multiple paths almost ideally despite of the disparity in their bandwidth. When a path with a delay of 100% greater is utilized as the second path, the throughput is enhanced about 20%.

• Journal of the Korean housing association
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• v.23 no.5
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• pp.1-8
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• 2012

Recently, there have been frequent occurrence of the damage to lives and properties due to the torrential rain caused by climate change. In consideration of the current situations in which the underlying data related to flooding are lacking, this study conducted to build up the basic data on the flooded areas and suggested methods to secure the evacuation routes that can be accessible to evacuation facilities in the residential buildings. Methods of the study are as follows. First, We calculated the flood risk grades of residential buildings based on elevations, considering the flooding characteristics of the flooded areas in Buk-gu, Daegu. Second, We constructed baseline data on the evacuation routes through site investigation and reviewed of drawing using Arc GIS to identify vulnerability to access to the evacuation facilities, targeting the residential buildings. Third, We carried out the proximity analysis through a near analysis of analysis functions in ARC GIS. Forth, We deduced 115 residential buildings in which access to evacuation facilities is considered to be difficult based on the analysis results. Finally, We proposed extension of a blind alley as a means for achieving connectivity to evacuation facilities. And to evaluate the alternatives presented, we reconstructed route data. As a result, about 53% improvement was identified through the proximity analysis.