• International Journal of High-Rise Buildings
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• v.12 no.2
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• pp.121-128
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• 2023

Cities cover only 3% of the planet's surface, yet they are responsible for more than 75% of the global emissions. Given the projected urban built area will double by 2060, the carbon emitted from cities will further increase. SOM proposes the Urban Sequoia concept, for buildings that go beyond 'net zero' and absorb carbon from the atmosphere. This concept combines multiple strategies, including the use of an optimised building form with a highly efficient structural system, modularized prefabrication techniques, holistic integration of facade, MEP and interiors' components, bio-based materials, and Direct Air Capture (DAC) technology, to reduce a 40-storey building's whole life cycle carbon emissions by more than 300% over a 100-year lifespan. Calculations of embodied carbon emissions are performed with SOM's in-house Environmental Analysis (EA) Tool to demonstrate the effectiveness of employing Urban Sequoia's design strategies in the design of new buildings using current technologies.

• Convergence Security Journal
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• v.23 no.4
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• pp.71-80
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• 2023

Cyberspace has emerged as the fifth domain of warfare, alongside land, sea, air, and space. It has become a crucial focus for offensive and defensive military operations. Governments worldwide have demonstrated their intent to engage in offensive cyber operations within this domain. This paper proposes an innovative offensive cyber kill chain model that integrates the existing defensive strategy, the cyber kill chain model, with the joint air tasking order (ATO) mission execution cycle and joint target processing procedure. By combining physical and cyber operations within a joint framework, this model aims to enhance national cyber operations capabilities at a strategic level. The integration of these elements seeks to address the evolving challenges in cyberspace and contribute to more effective jointness in conducting cyber operations.

• Journal of Digital Convergence
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• v.18 no.1
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• pp.73-81
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• 2020

The purpose of this paper is to analyze the efficiency of on-off-line integrated operations of listed retailers, propose ways to identify and improve the problems of inefficient enterprises, and accelerate the integration of on-off-line. The 28 listed retail companies selected total capital, management expenses, number of employees and wage rates as input factors as of 2018 and total operating income and operating profit were selected as output indicators to analyze efficiency using DEA. The results show that the integrated enterprise has a higher overall level of operational efficiency, but it is still in a state of stagnation. The pure technical efficiency of the integrated enterprise is generally higher, and the scale efficiency is the main reason that the overall efficiency of the enterprise is not improved. This study can help retail companies adjust their development strategies of online and offline integration according to their own degree of online and offline integration. This study has limitations in explaining the change in efficiency of retailers by conducting a cross-sectional analysis using data limited to 2018. It is necessary to utilize data over the next several years to conduct a longitudinal analysis.

• Journal of the Korea Society for Simulation
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• v.16 no.4
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• pp.23-31
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• 2007

Anti-Air Warfare(AAW) functionality of the naval combat system is the key functionality to ensure the ship's survivability. We have applied a novel method using model-based-simulation to analyze and design AAW functionality of the Patrol Killer Experimemnt Combat System. In this approach, an AAW functional model is described with the FSM(Finite State Machine) and directly executed for the AAW simulation. After prototyping using model based simulation, Hardware In Loop Simulation(HILS) is conducted as the AAW functionality is interfaced with the other ones of the combat system for completing the integration of the system components. This incremental and iterative development approach based on the model based simulation can minimize the development risks and costs caused by the system complexity for military system, bringing out the merit of the rapid prototyping.

• Journal of Korean Society for Atmospheric Environment
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• v.21 no.6
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• pp.561-571
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• 2005

To introduce an emissions trading system for GHG that currently have no reduction requirements, the following should be considered as priorities: eliciting the participation of the industrial sector and linking GHG emission trading systems to the emissions trading system (implemented from July 2007) that has become part of national policy with the enactment of the Special Act. Two directions can serve as viable alternatives in that regard. One is a baseline-and-credit method based on incentive auctioning. This has the advantage of inducing participation through economic incentives without a reductions commitment. The downside of this method is that it requires vast investments, as well as the fact that reaching an agreement between participants and the government to decide an objective baseline is difficult. On the other hand, the cap-and-trade method set forth in the Special Act is attractive in that it can be integrated with the air pollutant emissions trading system, but it would be difficult to elicit the participation of the industrial sector in the absence of GHG emission reduction requirements. In the current situation, it would be preferable for the government to induce the participation of the industrial sector by devising a wide variety of incentives because taking part in the emissions trading system before reducing GHG emissions offers large incentives through learning by doing. The timing of GHG reduction commitments and emissions trading system implementation may be uncertain but their Implementation will be unavoidable. Thus the government needs to facilitate preparations for emissions trading of GHG in the future and continuously review its operation in integration with the air pollutant emissions trading system to maximize adaptation and teaming by doing effect in the industrial sector.

• Journal of computational fluids engineering
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• v.18 no.1
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• pp.58-62
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• 2013

Personal Rapid Transit (PRT) is the emerging personal transport vehicle operating on the loop automatically. The PRT system utilize the electrical power from super capacity or battery, it is important to manage the power or energy. In this regards, the management of high temperature occurred by the operation of system is significantly important to prevent from serious damage of component. In this study, we studied the adequate shape of underbody which can reduce the heat accumulation by pickup coil and condenser using natural air cooling. We suggested the additional air pathway, air inlet and flow separator to decrease the temperature of the heat source components. It was found that suggested system can decrease the temperature of PRT under body by 16% during the static mode and by 10% during the running mode at 30km/h. It is expected that the findings of this study will feed into final design of newly built Korean PRT vehicle.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2005.04a
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• pp.295-300
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• 2005

The freeplay, one of the concentrated structural nonlinearities, is inevitable for control surfaces of a real air vehicle due to normal wear of components and manufacturing mismatches. Also aerodynamic nonlinearities caused by a shock wave occur in transonic region. In practice, these nonlinearities induce the limit cycle oscillation (LCO) and decrease the transonic flutter speed. In this study, the fictitious mass method is used to apply a modal approach to nonlinear structural models due to freeplay. The transonic small-disturbance (TSD) equation is used to calculate unsteady aerodynamic forces in transonic region. Nonlinear aeroelastic time responses are predicted by the coupled time integration method (CTIM). This method was also applied to a 3D all-movable control wing to investigate its nonlinear aeroelastic responses. The angle of attack effect on the LCO characteristics has been found to be closely related with the initial pitching moment.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.11a
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• pp.54-60
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• 2006

This study looks over the relation between propeller and noise in ship stern structure. Near field noise and vibration measurements are compared with the analytical results using wave number method. To avoid singularity in wave number integration method, fast field method is introduced. Analytical results show that main transmission mechanism of high frequency noise is structure-borne type and that of low frequency noise is a air-borne type.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.09a
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• pp.808-812
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• 2010

A great deal of attention is focused on coupled Thermo-Hydro-Mechanical (THM) behavior of multiphase porous media in diverse geo-mechanical and geo-environmental areas. This paper presents general governing equations for coupled THM processes in unsaturated porous media. Coupled partial differential equations are derived from 3 mass balances equations (solid, water, and air), energy balance equation, and force equilibrium equation. Finite element code is developed from the Galerkin formulation and time integration of these governing equations for 4 main variables (displacement $\underline{u}$, gas pressure $P_g$, liquid pressure $P_l$), and temperature T). The code is validated with theoretical solutions for linear material with simple boundary conditions.

• Journal of Internet Computing and Services
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• v.6 no.3
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• pp.31-43
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• 2005

OTAR system is a highly authentic key management system that has functions with access control. data integrity and data confidentiality, In this paper, we analyze the existing TIA/EIA Over-The-Air-Rekeying key managements protocol. focused to symmetric ciphers. It can be used to understand the technical trend on technologies about TIA/EIA OTAR standardization. This results can be used to evaluate security properties of a remote rekeying, The proposed system contains a highly reliable system synchronization.