• Journal of Environmental Science International
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• v.3 no.1
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• pp.39-47
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• 1994

Dispersion characteristics of air pollutants in the mountainous coastal area are investigated in considering with the mesoscale local circulations using a two dimensional numerical model with two kinds of topograpy of 500m and 300m. In the model, land-sea breezes and mountain-valley wind are mainly considered under the condition of the absence of large scale prevailing flow in the circulation analysis, and the pollutants dispersion is traced by the Lagrangian methods. According to the results, the wind velocity is affected by topography and is stronger in the case of 500m height mountain than that of 300m, the Pollutants that source is near the coast transported over the mountain and dispersed to behind inland area. It is classified that the topography change control affects the wind velocity and the circulations. The pollutants that source is different transported and concentrated to behind inland and/or diffused to the sea area by the combination of the wind system with topographic changes. The results can be applied to the air pollution control with the arrangement design of industrial area and the planning of coastal developments.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2018.05a
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• pp.415-418
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• 2018

To reduce the flooding overhead of typical AODV, we propose a local flooding initiated by a destination. The proposed routing protocol determines the one-hop neighbor nodes around the shortest path between source and destination by overhearing, and periodically generate flooding at the destination to cope with topology changes. This flooding process involves only one-hop neighbor nodes around the shortest path for reducing the flooding overhead and forms multiple alternate paths around the shortest path. This makes it possible to seamlessly route to the newest shortest path around when the current routing path is disconnected.

• Journal of Communications and Networks
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• v.7 no.3
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• pp.377-384
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• 2005

The purpose of this research is to develop and evaluate a traffic engineering architecture that uses local state information. This architecture is applied to an Internet protocol radio access network (RAN) that uses multi-protocol label switching (MPLS) and differentiated services to support mobile hosts. We assume mobility support is provided by a protocol such as the hierarchical mobile Internet protocol. The traffic engineering architecture is router based-meaning that routers on the edges of the network make the decisions onto which paths to place admitted traffic. We propose an algorithm that supports the architecture and uses local network state in order to function. The goal of the architecture is to provide an inexpensive and fast method to reduce network congestion while increasing the quality of service (QoS) level when compared to traditional routing and traffic engineering techniques. We use a number of different mobility scenarios and a mix of different types of traffic to evaluate our architecture and algorithm. We use the network simulator ns-2 as the core of our simulation environment. Around this core we built a system of pre-simulation, during simulation, and post-processing software that enabled us to simulate our traffic engineering architecture with only very minimal changes to the core ns-2 software. Our simulation environment supports a number of different mobility scenarios and a mix of different types of traffic to evaluate our architecture and algorithm.

• Convergence Security Journal
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• v.14 no.7
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• pp.9-15
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• 2014

In this paper, we proposed a new LDP code to solve a previous LDP code's problem and can include a face-color information. To include the face-color information, we developed various methods reducing the existing LDP code and analyzed the results. A new LDP code is represented by 6-bits different from the previous LDP code To adapt to a noise and environmental changes effectively and include 2-bits face-color information. The result shows better recognition rates of face and facial-expression than the existing methods effectively.

• Journal of Korean Society of Rural Planning
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• v.6 no.1 s.11
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• pp.10-18
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• 2000

The objective of this study is to analyze 1) the law system in relation with the development permissions 2) characteristics of the development permissions change 3) especially focusing on the development permissions changes in agricultural, forestry and fisheries facilities in light of socio - economic conditions in Korea Greenbelt. The following results were obtained: 1) The purpose of Greenbelt in Korea is to control the land use in order to protect the surrounding areas from urbanization. 2) During the 1990s, the number of formulated development regulations increased one and half times than that of the previous decades(1970s 1980s). The main reasons are advancements of local autonomy and democratization. 3) Three patterns were observed with respect to ease the regulations in agricultural, forestry and fisheries facilities those are: (1) increase in types of businesses ; (2) increase the maximum area permitted ; (3) decrease in qualification for establishing facilities. 4) There were few development permissions in a agricultural, forestry and fisheries facilities in consideration to the regional agricultural condition. The development permissions were only during the period of restricted to use ($1979.12{\sim}1993.11$). We propose that the authority of development permission should be given to the local autonomy government, because the local government has the knowledge of its individual agricultural conditions.

• Journal of Broadcast Engineering
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• v.15 no.2
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• pp.280-289
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• 2010

The H.264/AVC standard uses efficient inter prediction technologies improving the coding efficiency by reducing temporal redundancy between images. However, since H.264/AVC does not efficiently encode a video sequence that occurs a local illumination change, the coding efficiency of H.264/AVC is decreased when a local illumination change happens in video. In this paper, we propose an improved motion compensation using adjacent pixels and motion vector refinement to efficiently encode local illumination changes. The proposed method always improves the BD-PSNR (Bj$\o$ntegaard Delta Peak Signal-to-Noise Ratio) of 0.01 ~ 0.21 dB compared with H.264/AVC.

• Nuclear Engineering and Technology
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• v.50 no.1
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• pp.97-106
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• 2018

Improved load-following capability is one of the most important technical tasks of a pressurized water reactor. Controlling the nuclear reactor core during load-following operation leads to some difficulties. These difficulties mainly arise from nuclear reactor core limitations in local power peaking: the core is subjected to sharp and large variation of local power density during transients. Axial offset (AO) is the parameter usually used to represent the core power peaking. One of the important local power peaking components in nuclear reactors is axial power peaking, which continuously changes. The main challenge of nuclear reactor control during load-following operation is to maintain the AO within acceptable limits, at a certain reference target value. This article proposes a new robust approach to AO control of pressurized water reactors during load-following operation. This method uses robust feedback-linearization control based on the multipoint kinetics reactor model (neutronic and thermal-hydraulic). In this model, the reactor core is divided into four nodes along the reactor axis. Simulation results show that this method improves the reactor load-following capability in the presence of parameter uncertainty and disturbances and can use optimum control rod groups to maneuver with variable overlapping.

• Transactions of the Korean Society of Mechanical Engineers
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• v.14 no.5
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• pp.1300-1310
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• 1990

Naphthalene sublimation technique is employed to investigate the mass transfer processes from a square cylinder at various Reynolds numbers and various angles of attack. Distribution of the local mass transfer coefficients on each face of the cylinder changes dramatically with the angle of attack. Such variation of local mass transfer rates closely connected with the complex flow phenomena such as stagnation, acceleration, separation, reattachment and vortex shedding. The average Sherwood number has a minimum value at 12.deg.-13.deg., and a maximum value at a=20.deg.-25.deg. A comparison of present mass transfer measurement with other heat transfer measurements, using the heat/mass transfer analogy, shows good agreement in average transfer rates, same trend but notable differences in local values. Therefore, naphthalene sublimation technique can be adopted to explore heat transfer processes in the complex flow situations, which is considered to be hardly possible with the conventional heat transfer measurements.

• Journal of National Security and Military Science
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• s.2
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• pp.23-89
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• 2004

The protective area of military installations can be a essential investment goods for producting public goods like military installations and national security. For the purpose of this, The protective area of military installations are set up and applicated at important strategic areas. It causes colplications and frictions among the people, government and army inevitably to set up the protective area of military installations, as the relation between the army which produces security or public goods and the people that make and use valuable goods is opposed and contradictory to each other. Heretofore, the civil petition of the protective affair to military installations has been presented individually. As local self- government is fixed, a local selg-governing body presents many civil petitions now. Therefore the protective affair to military installations came to be examined carefully in the aspecs of improving the relationship between the civil and army, raising natinal competitiveness, and increasing efficiency of military operations. Though the relationship between the civil and army is opposed and contradictory, it is required to be in keeping with each other with a situation around society, that is, changes and trend of national security, politics, economy, society. Accordingly, if you drive plans of rational management to the protective area of military installations, you can not only achieve successful military installations, but also be a great help to growth of a local community. Then 「The Army with the people」worthy of the name can be real.

• Journal of Ocean Engineering and Technology
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• v.30 no.6
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• pp.484-497
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• 2016

In order to understand the characteristics of the topography change in front of an impermeable breakwater, a coupled model for a two-way analysis of the existing LES-WASS-2D and newly developed morphodynamic model was suggested. A comparison to existing experimental results revealed that the results computed using the 2-D hydro-morphodynamic model were in good agreement with the experimental results for the wave form, pore water pressure in the seabed, and topographical change in front of a submerged breakwater. It was shown that the two-way model suggested in this study is applicable to a morphological change in the seabed around a submerged breakwater. Then, using the numerical results, the topographical changes in front of an impermeable submerged breakwater were examined in relation to partial standing waves. Moreover, the characteristics of the local scour depths in front of them are also discussed in relation to incident wave conditions, sediment qualities, and submerged breakwater shapes.