• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.46 no.11
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• pp.952-960
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• 2018

Recently, lots of remote sensing satellite require agility to collect more images within the limited time frame. To satisfy this kind of mission requirement, high torque actuator such as CMG is an essential element. In this study, 5Nm class small CMG developed by KARI is introduced to implement for an agile small satellite design. One of the singularity escape CMG steering law, Designated Direction Escape (DDE) method, which is a sort of modified version of Singular Direction Avoidance (SDA) method is summarized for its application on the numerical simulation of agile attitude control system design result. The performance of DDE method is demonstrated properly by escaping well known elliptic internal singularity successfully. 5Nm class small CMG cluster in a pyramid type as well as a roof type configuration is utilized to perform the numerical simulation and to demonstrate its agility design result for a small satellite. Simulation result shows the properness of 5Nm small CMG to a small agile satellite system. Also, the simulation result provides some valuable information that is important to CMG hardware design and manufacturing.

• Journal of Institute of Control, Robotics and Systems
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• v.10 no.7
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• pp.658-668
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• 2004

This paper is concerned with a control allocation strategy using the dynamic inversion and the pseudo inverse control which generates the nominal control input trajectories. In addition, an autopilot design method is proposed by using time-varying control technique which is time-varying version of the pole placement of linear time-invariant system for an agile missile with aerodynamic fin and thrust vectoring control. The control allocation proposed in this paper is capable of extracting the maximum performance by combining each control effector, aerodynamic fin and thrust vectoring control. The adopted time-varying control technique for the autopilot design enhances the robustness of the tracking performance for a reference command. The main results are validated through the nonlinear simulations with aerodynamic data.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.525-530
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• 2003

This paper is concerned with a control allocation strategy using the dynamic inversion which generates the nominal control input trajectories, and autopilot design using the time-varying control technique which is time-varying version of pole placement of linear time-invariant system for an agile missile with aerodynamic fin and thrust vectoring control. Dynamic inversion can decide the amount of the deflection of each control effector, aerodynamic fin and thrust vectoring control, to extract the maximum performance by combining the action of them. Time-varying control technique for autopilot design enhance the robustness of the tracking performance for a reference command. Nonlinear simulations demonstrates the dynamic inversion provides the effective nominal control input trajectories to achieve the angle of attack command, and time-varying control technique exhibits good robustness for a wide range of angle of attack.

• International Journal of Contents
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• v.12 no.3
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• pp.29-33
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• 2016

Cloud computing makes extensive use of virtual machines that permit for workloads, as well as resource usage, to be isolated from one another, and a hypervisor can be used by a virtual machine to construct cloud computing infrastructure. However, the hypervisor has high resource usage when constructing virtual machines, which results in a waste of allocated resources when not activated. Docker provides a more light-weight method to obtain agile computing resources based on a container technique that handles this problem. In this study, we have chosen this specific tool due to the increasing popularity of MapReduce and cloud container technologies such as Docker. This study aims to automatically configure Twister workloads for container-driven clouds. Basically, this is the first attempt towards automatic configuration of Twister jobs on a container-based cloud platform VM for many workloads.

• Asia pacific journal of information systems
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• v.9 no.3
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• pp.177-194
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• 1999

Identifying knowledge as the single most important asset ultimately defining organizational competitiveness, enterprises are trying to move towards knowledge-oriented practices. Such practices have given rise to learning and agile organization, This paper presents applied information technologies to realize the learning and agile organization, focusing on systems thinking. Firstly, in order to establish a framework for the systems thinking, an information systems development method based on process chain is proposed. Then, an agent-based microworld simulation approach is presented. The approaches provide visible and analytical information to knowledge workers so that they can have systems thinking capabilities eventually. Various microworlds on the top of the information system can be constructed with agents and simulated for possible business events. All decision makings are dynamic in nature. To let knowledge workers look ahead the possible outcomes of the whole relevant processes is the core capability of the approaches. Through watching, the knowledge workers would be able to acquire new insights or problem solving knowledge for the problem in hand.

• Proceedings of the Korea Information Processing Society Conference
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• 2005.11a
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• pp.377-380
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• 2005

최근 다양한 분야에서 임베디드 소프트웨어의 비중이 증대함에 따라 품질 요구 사항이 증대 하였지만, 현실적인 개발 일정은 점점 줄어들고 있다. 이에 본 논문에서는 임베디드 소프트웨어의 기민한 속성 주도 설계(Agile Attribute-Driven Design)를 체계적으로 적용하기 위한 '통합 분석 기법'을 정의한다. 그리고 이를 통한 기민한 설계 접근법을 제안한다. '통합 분석 기법'은 임베디드 소프트웨어의 특성을 고려한 기능 분석과 동시에 '품질 속성 시나리오'를 분석할 수 있는 기법으로서 고품질의 아키텍처 구축을 목적으로 한다. 또한 본 논문에서는 개미 로봇 구현 사례를 통해 '통합 분석 기법'을 검증하고 효과를 확인한다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.10a
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• pp.81-84
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• 2002

With the increasing market dynamics, the concept of agile manufacturing system gets more and more attention. For a manufacturing system to be agile, the supply chain should also have sufficient agility. However, most of the supply chain design methods are based on the human experience or trial-and-errors. In this paper, a systematic methodology is proposed. It takes into account the agility of supply chain, the behavior of which is represented as a beam model in mechanics, composed of supplier, transporter, manufacturer, distributor, and customer.

• International Journal of Control, Automation, and Systems
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• v.6 no.2
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• pp.278-281
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• 2008

Linear motor (LM) based shuttle cars will play an important role in the future transportation systems of marine terminals to cope with increasing container flows. These systems are known as agile port terminals because of their significant advantages. However, routing for multiple shuttle cars is still an open issue. We present a network model of a container yard and propose constrained dynamic programming (DP) for its routing strategy with collision avoidance. The algorithm is a modified version of typical DP which is used to find an optimal path for a single traveler. We evaluate the new algorithm through simulation results for three shuttle cars in a mesh-type container yard.

• Proceedings of the Safety Management and Science Conference
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• 2003.05a
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• pp.299-304
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• 2003

Manufacturing companies must possess a new type of production system with characteristics of reconfigurability, reusability and scalability (Dove 1995), i.e. an agile manufacturing system. Such system will allow flexibility not only in producing a variety of part, but also in changing the system itself, which is a difference form flexible manufacturing systems. A fundamental early step in the reconfiguring process for agile manufacturing system is to develop a model that adequately describes the proposed systems, in order to be able to study and evaluate the impact of the reconfiguring decision on the system performance, before its construction. Therefore, in this paper, an Object & Knowledge-based Interval Timed Petri-Net (OKITPN) approach is proposed.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.99.6-99
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• 2001

The parameter optimization for agile beam radar tracking is addressed to minimize the radar resources that are required to maintain a target under track. The parameters to be optimized include the track-revisit interval and the sequence of pairs of target signal strengths and detection thresholds associated with repeated illumination attempts in each track-revisit. The optimization problem is solved numerically for typical examples.