• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 G
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• pp.2473-2475
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• 1998

In this paper, we implemented RS232C serial communication by the 2 wires(Data,GND), and multiple access, by the applying Collision Sensing Multiple Access(CSMA) Protocol. Multiple access is implemented by assigning a unique ID to each controller. The multiple access control operation starts by sending a command packet from a host to another host and the command packet is composed of ID bytes of source and target host computer, data bytes and the check sum, byte. In host computer, after sending command packet, the collision from loop back data. If collision is detected, it means a command packet was collided with another command packet for another host. The packet communication of the controller enables the multiple acces of the controller through the common serial data link. The application of this serial communication through CSMA protocol and the usage of two wires, have an effect on saving the wires and convenient of layout work.

• 한국정보통신학회논문지
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• 제4권1호
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• pp.115-121
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• 2000

입력제어신호 변형은 유연한 빔의 진동을 감소시키는 중요한 수단이다. 본 논문에서는 유한시간에서 다중 모드인 유연한 빔의 오차 진동을 제거하는 매우 단순한 입력제어신호 변형 방법을 소개한다. 제어신호는 선형 방정식의 풀이에 의해 구성되어 진다. 유한시간 동안 원하는 동작의 모터 각도는 임의의 한정된 오차 진동을 제거함으로서 도달된다. 폐루프 구성에서 모터 각도에 대한 기준입력으로서의 제어신호 사용에 대한 필요한 조건들 또한 다루게 된다. 제안된 시스템 구성의 효과는 컴퓨터 시뮬레이션을 통해 증명된다.

• 한국군사과학기술학회지
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• 제14권6호
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• pp.1031-1036
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• 2011

In this paper, we have proposed a methodology which can test and evaluate on system level in development phase of command guided missile system. Test and evaluation play a significant role in the development of weapon system, providing the means for determining to what extent the weapon system satisfies its requirements, whether it functions normally in the operational environment. In case of command guided missile having seeker, the missile communications link provides data to allow the missile to fly an efficient trajectory toward target. Therefore, it is very important to test and evaluate for data link between missile and radar on whole system aspect. we introduce the concept and devices for system level test and evaluation of command guided missile system.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2001년도 ICCAS
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• pp.54.2-54
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• 2001

In this paper two control strategies, command shaping control and optimal control, which aim to the reduction of the residual vibrations of the payload in a container crane system are investigated. Both control methods are open loop control. Due to unmodeled dynamics of the plant and disturbances like initial sway and wind, some residual sway always exists at the end of trolley movement. Command inputs are designed to achieve the control objectives including minimal residual vibration and robustness in the presence of unmodeled dynamics. Simulation results of various command inputs are compared in terms of arrival time, residual sway angle, robustness, and maximum sway distance during the traveling. Command shaping method provides a more competent tool than optimal control.

• 한국컴퓨터정보학회논문지
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• 제23권1호
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• pp.49-55
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• 2018

In this paper, we propose a design and development of instructional cards to understand the grammar of coding, solving the problems and extending the computational thinking in the robot-driven environment. First, we designed the input/output module of the robot to process the coding grammar through the function analysis of the robot. And we designed the module of command card to learn coding grammar using color sensors. We have proven the validity of the designed instruction card by examining the experts to see if it is suitable for coding grammar learning. Designed robot and command card were developed with 28 cards and sensor robot. After applying the developed robot and command card to the elementary school students, the questionnaire showed that students grow the understanding and confidence of coding. In addition, students showed an increased need for programming learning.

• 대한임베디드공학회논문지
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• 제13권6호
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• pp.321-328
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• 2018

This paper presents an automatic target tracking flight system using a PID controller based on velocity command of a multirotor UAV. The automatic flight system includes marker based onboard target detection and an automatic velocity command generation replacing manual controller. A quad-rotor UAV is equipped with a camera and an image processing computer to detect the marker in real time and to estimate the relative distance from the target. The marker tracking system consists of PID controller and generates velocity command based on the relative distance. The generated velocity command is used as the input of the UAV's original flight controller. The operation of the proposed system was verified through actual flight tests using a marker on top of a moving vehicle and tracks it to successfully demonstrate its capability using a quad-rotor UAV.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2013년도 추계학술발표대회
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• pp.1070-1073
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• 2013

위성 비행 소프트웨어의 개발 과정에는 소프트웨어의 신뢰성을 향상하기 위한 다양한 검증 활동이 이루어진다. 이러한 검증 활동에는 효율적으로 설계된 검증 환경이 필수적이다. 위성 비행 소프트웨어 개발 전반에 검증 환경을 효과적으로 적용하기 위해서는 사용 가능한 검증 환경이 보다 빠르게 구현되어야 한다. 검증 환경은 개념적으로 궤도 상의 위성과 통신하는 지상 시스템의 역할을 기본으로 하고 있으므로 Command 송신과 Telemetry 수신을 위성 비행소프트웨어와의 상호 작용으로 정의할 수 있다. 따라서 위성 비행소프트웨어의 동작을 Command와 Telemetry 관점에서 모델링하고 이를 모사하는 시스템을 이용함으로써 위성 개발 초기부터 위성 비행 소프트웨어 검증 환경 구현에 사용할 수 있고, 또한 위성 개발 과정에서 발생하는 다양한 변경 사항을 보다 효과적으로 반영할 수 있다. 본 논문에서는 위성 비행 소프트웨어의 검증 환경 구현을 위한 Command Telemetry Simulator의 설계 및 그 구현에 대하여 소개한다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제7권3호
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• pp.576-599
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• 2013

Protocol reverse engineering is useful for many security applications, including intelligent fuzzing, intrusion detection and fingerprint generation. Since manual reverse engineering is a time-consuming and tedious process, a number of automatic techniques have been proposed. However, the accuracy of these techniques is limited due to the complexity of binary instructions, and the derived formats have missed constraints that are critical for security applications. In this paper, we propose a new approach for protocol format extraction. Our approach reasons about only the evaluation behavior of a program on the input message from concolic execution, and enables field identification and constraint inference with high accuracy. Moreover, it performs binary analysis with low complexity by reducing modern instruction sets to BIL, a small, well-specified and architecture-independent language. We have implemented our approach into a system called Icefex and evaluated it over real-world implementations of DNS, eDonkey, FTP, HTTP and McAfee ePO protocols. Experimental results show that our approach is more accurate and effective at extracting protocol formats than other approaches.

• 대한인간공학회지
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• 제31권4호
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• pp.525-531
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• 2012

Objective: The aim of this study is to investigate learnability of gestures-commands pair when people use gestures to control a device. Background: In vision-based gesture recognition system, selecting gesture-command pairing is critical for its usability in learning. Subjective preference and its agreement score, used in previous study(Lim et al., 2012) was used to group four gesture-command pairings. To quantify the learnability, two learning models, average time model and marginal time model, were used. Method: Two sets of eight gestures, total sixteen gestures were listed by agreement score and preference data. Fourteen participants divided into two groups, memorized each set of gesture-command pair and performed gesture. For a given command, time to recall the paired gesture was collected. Results: The average recall time for initial trials were differed by preference and agreement score as well as the learning rate R driven by the two learning models. Conclusion: Preference rate agreement score showed influence on learning of gesture-command pairs. Application: This study could be applied to any device considered to adopt gesture interaction system for device control.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제17권9호
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• pp.2419-2435
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• 2023

Command and control networks(C2N) exhibit evident multi-network interdependencies owing to their complex hierarchical associations, interleaved communication links, and dynamic network changes. However, the existing command and control networks do not consider the effects of dependent nodes on the load distribution. Thus, we proposed a command and control networks load allocation strategy based on interdependence strength. First, a new measure of interdependence strength was proposed based on the edge betweenness, which was followed by proposing the inter-layer load allocation strategy based on the interdependence strength. Eventually, the simulation experiments of the aforementioned strategy were designed to analyze the network invulnerability with different initial load capacity parameters, allocation model parameters, and allocation strategies. The simulation indicates that the strategy proposed in this study improved the node survival rate of the interdependent command and control networks model and successfully prevented cascade failures.