• Journal of the Economic Geographical Society of Korea
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• v.11 no.2
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• pp.175-191
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• 2008

In the early stage of industrial development, most of software companies were agglomerated at the CBD(Central Business Districts) in Seoul. However, the spatial distribution pattern of Korean Software industry has been changed according to the propagation of broadband, the change in rents, the governmental policy for industrial districts. In this research, using the software year book at 1997 and 2007, the emerging new pattern was analyzed using spatial clustering analysis. As a results of research, the spatial distribution was expanded in morphological changes. However, it was found that there was not a significant difference in a degree of accumulation. In the aspect of behavioral movement of companies, they tend to be relocated from the CBD to urban fringes and their movement is related to the product life cycle in selecting the clustered place.

• Structural Engineering and Mechanics
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• v.37 no.6
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• pp.671-684
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• 2011

Deciding on an optimal sensor placement (OSP) is a common problem encountered in many engineering applications and is also a critical issue in the construction and implementation of an effective structural health monitoring (SHM) system. The present study focuses with techniques for selecting optimal sensor locations in a sensor network designed to monitor the health condition of Dalian World Trade Building which is the tallest in the northeast of China. Since the number of degree-of-freedom (DOF) of the building structure is too large, multi-modes should be selected to describe the dynamic behavior of a structural system with sufficient accuracy to allow its health state to be determined effectively. However, it's difficult to accurately distinguish the translational and rotational modes for the flexible structures with closely spaced modes by the modal participation mass ratios. In this paper, a new method of the OSP that computing the mode shape matrix in the weak axis of structure by the simplified multi-DOF system was presented based on the equivalent rigidity parameter identification method. The initial sensor assignment was obtained by the QR-factorization of the structural mode shape matrix. Taking the maximum off-diagonal element of the modal assurance criterion (MAC) matrix as a target function, one more sensor was added each time until the maximum off-diagonal element of the MAC reaches the threshold. Considering the economic factors, the final plan of sensor placement was determined. The numerical example demonstrated the feasibility and effectiveness of the proposed scheme.

• Journal of the Korean Association of Geographic Information Studies
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• v.16 no.2
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• pp.30-46
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• 2013

Using ArcGIS Model Builder, with emphasis on the importance of ecology and user friendliness, a model for site selecting tool is developed. This tool is developed by establishing standardized method for data selection and analysis with evaluation criteria using GIS. For this task, our first action was to objectively define and establish 18 elements to evaluate the potentiality of the site based on extensive literature reviews. These 18 elements reflect environmental, social/cultural and legal aspects that may influence the decision process to select the desired site. Secondly, using ArcGIS Model Builder, 18 analytical elements were made into thematic mapping which represent systematically organized graphic input to the model with automatic double check system and overlay analysis capability. Thirdly, to validate the effectiveness of the developed model, site location analysis was performed using the actual site, Buk-ku, Pohang.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2002.11a
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• pp.880-883
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• 2002

In this paper, we propose the synchronization recovery algorithm which is suitable to wireless multimedia of wireless channel situation which is being used OFDM signaling method. The basic of the suggested clock synchronization. restoration Algorithm is to getting the shock response of channel or getting the multipath strength profile through IFFT after the getting the frequency, response of deducted channel from channel deductor of receiver and to trace the location in the channel energy concentrated area of timing area. And it also analysis the start point of 64-QAM and 16-QAM if the sampling clock offset has the sample of $\pm$1-3, and we identified the occurance of performance deterioration when occures more than 2 samples of offset to compare with star point and BER performance in optimum sampling point result of BER performance checking, and we know that the recovery algorithm proposed algorithm also provide excellent synchronization characteries under frequency, selecting fading channel as result of simulation.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2002.05a
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• pp.205-208
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• 2002

When establishing the submarine optical fiber table between international and domestic, marine survey in advance it grasps the submarine geological features which is accurate and a depth of water condition. And the route which is safe for selecting and submarine optical fiber cable laying it is a work which secures an ease one location. If also, the PLGR the submarine of optical fiber table root the sea contamination material (rope, wire and net) it removes in advance and if the submarine of the optical fiber cable ease it does to arrive safely. And it is a work the Plough and ROV laying work hour laying work efficiency improvement and laying equipment it will be able to protect. So, This paper presents the monitoring system of ship information management and operation for marine survey and PLGR work in submarine optical fiber table construction enterprise. In order to achieve these purpose, overall serial multi-port communication modulo of configuration, realtime processing for management and operation of receiving data, realtime graph and a printout are described.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.4
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• pp.831-840
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• 2010

While Wireless Internet services were activated, many users got possible to use various Internet services without limitation in location. In particular, the demands to Wireless Internet Services are getting expanded because mobile devices that support high mobility are getting smarter. However, if a user uses various wireless networks, much limitation occurs in network setting when they move to another network. This is because there are few appropriate Handover Mechanisms to support Heterogeneous Network. So, this paper propose that Fast-Handover for Vertical Network Handover with MIH in PMIPv6 to support heterogeneous network and to reduce the handover latency time. Analysis result presented in this paper shows that by carefully selecting suitable system configuration model and parameters, suggestion has reduced latency time of 26% and packet losses of 90% (Avg.) at the maximum in comparison with original PMIPv6 handover.

• Journal of the Korea Society of Computer and Information
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• v.19 no.6
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• pp.49-59
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• 2014

Recently, wireless sensor networks(WSNs) are widely used for intrusion detection and ecology, environment, atmosphere, industry, traffic, fire monitoring. In this paper, an energy efficient clustering algorithm is proposed. The proposed algorithm forms clusters uniformly by selecting cluster head that optimally located based on receiving power. Besides, proposed algorithm can induce uniform energy consumption regardless of location of nodes by multi-hop transmission and MST formation with limited maximum depth. Through the above, proposed algorithm elongates network life time, reduces energy consumption of nodes and induces fair energy consumption compared to conventional LEACH and HEED. The results of simulation show that the proposed clustering algorithm elongates network life time through fair energy consumption.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.23 no.4
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• pp.285-291
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• 2011

In this study the mechanical performance of the new wave dissipating block is evaluated through experiment and numerical analysis. Also, by selecting adequate reinforcement, the improvement of the structural performance is examined. The reinforcement is designed by predicting the amount of tensile force and the location where the tensile stress develops in the new wave dissipating block through numerical analysis. The new wave dissipating block is reinforced with the ordinary steel bars and the fiber reinforced plastic(FRP) bars which have advantages in ocean environment in terms of corrosion and fatigue. The test result shows that the fracture resistance of the un-reinforced concrete block is 350 kN which is about 6.2 times that of the weight of the block. All the test blocks which are reinforced by either steel of FRP bars show strength capacity of over 900 kN which is the maximum load of the test equipment. Although the single reinforcement with larger-diameter bars has advantage in terms of construction convenience, it is recommended to use multiple number of smaller-diameter bars in order to reduce the crack width.

• Journal of the Korean Society of Safety
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• v.29 no.4
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• pp.48-53
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• 2014

This study is analyzed for electrical fire danger by electric equipments through surveys of stable owners and the field investigation at 64 stable. Also, an experiment is performed to analyze the thermal characteristics of 4 types electric wiring according to the number of operating halogen warm lamp group and automatic waterer group in Beon-young stable in the Cheongwon location. The survey is done to investigate the occurrence of electrical fire, electric equipment, causes and dangerous equipment. As a result, halogen warm lamp group and automatic waterer group are found to have dangerous loads. In the field investigation, the mode of load capacity of the halogen warm lamp group and automatic waterer group was investigated. The mode of load capacity of halogen warm lamp group (over 3 years) is found 17A and that of the auto waterer group (10 years) is 16A. In this experiment, the halogen warm lamp group aged at least 3 years showed $109^{\circ}C$ while that aged less than 1 year appeared $83^{\circ}C$, showing the max gap of $26^{\circ}C$. The automatic waterer group aged 10 years showed $90^{\circ}C$ while that aged less than 1 year appeared $68^{\circ}C$, showing the max gap of $22^{\circ}C$. These findings indicate that the mode of load capacity needs to be considered in selecting and installing wiring for the electric equipment construction of halogen warm lamp group and automatic waterer group in stable.

• Journal of the Korean association of regional geographers
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• v.20 no.3
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• pp.300-314
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• 2014

The study is to systematically review "DaedongYeojiJeondo", the mid-sized wood block map of Chosun to shed light on the cartographic characteristics not discovered by previous studies. First it was discovered that Kim Jung-ho is the developer of the map as the distance information from Seoul to towns is identical with the information on "Daedong Jiji" the manuscript map drawn by Kim Jung-ho himself (assumed to live from 1804~1866) that is still remaining unfinished. Second, the information Kim Jung-ho wanted to specify most precisely and specifically was distance from Seoul to towns and for this purpose he invented unique symbols for towns in tiny size on the map. Third, in selecting information to mark on the map including road network, street information, mountain routes and streams and location of islands, "DaedongYeojiJeondo" is not just a simple smaller copy of "DaedongYeojido" but an independent creative work as it is much different in many aspects of quality. Forth, but still "DaedongYeojiJeondo" and "DaedongYeojido" have something in common in the fact both of them tried to mark land and mountain routes and streams most precisely and specifically.