• Proceedings of the Korean Operations and Management Science Society Conference
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• 1994.04a
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• pp.29-37
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• 1994

It is reported that north Korea has already developed 1,500 to 2,000-km-range Scud missile. As a defensive strategy against Scud attack on military and civilian facilities the military authorities are considering deployment of Patriot missile. This paper deals with its optimal deployment strategy. In this problem a Patriot missile which has multiple-facility responsibility may be able to protect each of its assigned facilities only with a certain probability, not absolute protection, and it may not be adequate to have only a single missile protect a facility, either because of its operational reliability or because of its limited availability at any given point in time. We formulate this problem into the probabilistic partial set covering model developed by Sherali and Kim. The applicability, verification and validation of the model are tested via an abbreviated case study.

• Journal of Industrial Technology
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• v.28 no.A
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• pp.113-117
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• 2008

Wireless carrier sense multiple access (CSMA) systems are widely used but show extremely different transmission efficiency according to the operation environment. Simulation or prototype deployment is needed to see the transmission efficiency of a wireless CSMA system with the partial packet retransmission scheme. The lower bound for the transmission efficiency of such a system is found mathematically in this work. This shows how much the partial packet retransmission scheme improves the transmission efficiency quantitatively. It also shows that the maximum throughput is obtained at higher offered load compared to the conventional CSMA system without the partial packet transmission. The result of this work can be applied to IEEE 802.11 networks or wireless mesh networks.

• Journal of Communications and Networks
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• v.18 no.6
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• pp.948-961
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• 2016

Internet protocol (IP) spoofing is a serious problem on the Internet. It is an attractive technique for adversaries who wish to amplify their network attacks and retain anonymity. Many approaches have been proposed to prevent IP spoofing attacks; however, they do not address a significant deployment issue, i.e., filtering inefficiency caused by a lack of deployment incentives for adopters. To defeat attacks effectively, one mechanism must be widely deployed on the network; however, the majority of the anti-spoofing mechanisms are unsuitable to solve the deployment issue by themselves. Each mechanism can work separately; however, their defensive power is considerably weak when insufficiently deployed. If we coordinate partially deployed mechanisms such that they work together, they demonstrate considerably superior performance by creating a synergy effect that overcomes their limited deployment. Therefore, we propose a universal anti-spoofing (UAS) mechanism that incorporates existing mechanisms to thwart IP spoofing attacks. In the proposed mechanism, intermediate routers utilize any existing anti-spoofing mechanism that can ascertain if a packet is spoofed and records this decision in the packet header. The edge routers of a victim network can estimate the forgery of a packet based on this information sent by the upstream routers. The results of experiments conducted with real Internet topologies indicate that UAS reduces false alarms up to 84.5% compared to the case where each mechanism operates individually.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.4 no.2
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• pp.323-336
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• 2000

In order to achieve the deployment of B-ISDN services in a short time, B-ISDN is being combined with terrestrial ATM network and satellite network which covers a widespread service range. This paper analyzes and investigates several previously existent CDV compensation methods in order to compensate CDV arising from interfacing satellite TDMA and ATM. Specifically to supplement the problems of timestamp and cell number counting methods, new Partial Timestamp mechanism for CDV compensation is proposed. The CDV compensating efficiency of the proposed mechanism is analyzed and evaluated by simulations. It goes to show that Partial timestamps mechanism has many advantages in the aspect of the CDV compensation.

• Fashion & Textile Research Journal
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• v.11 no.1
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• pp.24-32
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• 2009

The purpose of this study is to understand characteristic of expression in Korean style fashion design and investigated Korean style fashion design's deployment and design idea method as well as its esthetic value. The photographs for the research were selected from fashion collections during S/S 2003-F/W 2007 by four specialists in the department of textile and then analyzed with 288 final data. The results were as followings. First, the characteristics of design expression in Korean style fashion design were formation by separating partial shape from the whole, formation by shape's separation and repetition, and connecting formation by combination and transformation of parts. In the case of color, they were direct expression, contrasting formative expression, and gradual changing expression. In the case of pattern, they were the methods of filling, filling & emptying, and partial filling. Second, the deployments of Korean style fashion design were adding modern elements to traditional things, combining traditional elements and modern things, and adding traditional elements to modern things. The third, Korean style fashion design's idea methods were weaving, snatching, adding, and changing. Fourth, it was shown that esthetic values of Korean style fashion design were the interactive organism by building organic relationship, the optimum expressing beauty with minimum elements, the palpitation having dynamics and rhythmical beauty.

• The Transactions of the Korea Information Processing Society
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• v.7 no.9
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• pp.2980-2993
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• 2000

In order to achieve the rapid deployment of services. B-ISON network is being combined with terrestrial ATM and satellite network. Cell delay variation (CDV) generated by the difference of transfer mode between TOMA and ATM deteriorates transmission quality of the network system. We proposed the Partial Timestamps algorithm to supplement the problems of existing COV compensation methods. To minimize CDV and to utilize the satellite channels efficiently. only the optimized timestamps of a few cells within a control unit time of TDMA are selected and transmitted to the receiving earth station. The COV compensating efficiency of Partial Timestamps is evaluated by simulation. It is confirmed that CDV compensation capability of the proposed mechanism is superior to the other methods.

• International Journal of Aeronautical and Space Sciences
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• v.8 no.2
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• pp.89-97
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• 2007

COMS(Communication, Oceanography, and Meteorology Satellite) is the first Korean multi-purpose satellite which is planned to be deployed at the altitude of geosynchronous orbit above the Korean peninsular. Noting that COMS is composed of the main BUS structure, two deployable solar panels, one yoke, five reactions wheels, COMS is treated as a collection of 9 bodies and its nonlinear equations of motion are obtained using the multi-body dynamics approach. Also, a computer program is developed to analyze the COMS motion during the various mission phase. Quite often, the equations of motion have to be derived repeatedly to reflect the fact that the spacecraft dynamics change as its configuration, and therefore its degree of freedom varies. However, the equations of motion and simulation software presented in this paper are general enough to represent the COMS dynamics of various configurations with a minimum change in input files. There is no need to derive the equations of motion repeatedly. To show the capability of the simulation program, the spacecraft motion during the solar array partial and full deployment has been simulated and the results are summarized in this paper.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.43 no.4
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• pp.217-228
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• 2020

The ROK Army must detect the enemy's location and the type of artillery weapon to respond effectively at wartime. This paper proposes a radar positioning model by applying a scenario-based robust optimization method i.e., binary integer programming. The model consists of the different types of radar, its available quantity and specification. Input data is a combination of target, weapon types and enemy position in enemy's attack scenarios. In this scenario, as the components increase by one unit, the total number increases exponentially, making it difficult to use all scenarios. Therefore, we use partial scenarios to see if they produce results similar to those of the total scenario, and then apply them to case studies. The goal of this model is to deploy an artillery locating radar that maximizes the detection probability at a given candidate site, based on the probability of all possible attack scenarios at an expected enemy artillery position. The results of various experiments including real case study show the appropriateness and practicality of our proposed model. In addition, the validity of the model is reviewed by comparing the case study results with the detection rate of the currently available radar deployment positions of Corps. We are looking forward to enhance Korea Artillery force combat capability through our research.

• Asia pacific journal of information systems
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• v.9 no.2
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• pp.117-132
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• 1999

Common system deployment is one of the global information systems strategies of a multinational corporation for large-scale development that can provide economies of scale and optimal use of scarce technical expertise. But while the same (headquarter) team implements the same system, the resulting efficiencies of those projects differ widely among the subsidiaries. This paper focuses on the differences between the efficiencies of these implementation projects. Eight prepropositions about the factors causing the differences have been developed from the previous research. These prepropositions are explored through a case study on the twelve overseas subsidiaries of a multinational electronic corporation headquartered in Korea. We found that three factors(autonomy of subsidiary, complexity of task, experience level of users) have strong relevant relationships and two factors(level of subsidiary country, level of process formality) have partial relevant relationships with the implementation outcome.

• International Journal of Naval Architecture and Ocean Engineering
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• v.1 no.2
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• pp.89-94
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• 2009

The current focus of development in industrial Computational Fluid Dynamics (CFD) is integration of CFD into Computer-Aided product development, geometrical optimisation, robust design and similar. On the other hand, in CFD research aims to extend the boundaries of practical engineering use in "non-traditional" areas. Requirements of computational flexibility and code integration are contradictory: a change of coding paradigm, with object orientation, library components, equation mimicking is proposed as a way forward. This paper describes OpenFOAM, a C++ object oriented library for Computational Continuum Mechanics (CCM) developed by the author. Efficient and flexible implementation of complex physical models is achieved by mimicking the form of partial differential equation in software, with code functionality provided in library form. Open Source deployment and development model allows the user to achieve desired versatility in physical modeling without the sacrifice of complex geometry support and execution efficiency.