• Proceedings of the Korea Information Processing Society Conference
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• 2017.11a
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• pp.961-964
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• 2017

드론의 대중화에 따른 사고위험의 증가로 안전한 조종 방법에 대한 연구의 필요성이 대두되었다. 따라서 조종자의 조종능력에 구애받지 않는 자율비행제어기술이 필요하게 되었고, 이를 보다 안정적으로 구현하기 위하여 자율주행 소프트웨어 플랫폼으로 주목받고 있는 Robot Operating System(ROS)를 사용하였다. ROS를 기반으로 Laser Range Finder(LRF)와 Particle Filter를 사용하여 자율적으로 객체추적이 가능하며 지능적으로 장애물을 회피하여 비행 할 수 있는 안정적인 자율비행제어시스템을 구현하고자 한다.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.29 no.1
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• pp.77-83
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• 2005

In collision avoidance problem of a ship, collision risk model is usually set up using the interview results fron experts who sit on a simulator by varying parameters, in which DCPA and TCPA are commonly used. This method, however, has the weakness in that not only it is expensive but also it shows different results depending on the inerviewees and other navigational parameters. In this study, a fuzzy inference system is designed based on own ship's maneuverability verified fron simulation instead of interviewing navigators. The time and distance corresponding to the collision risk value on which avoidance maneuver should be started are set to the minimum marginal time at which own ship starts maneuvering and the minimum marginal distance suggested by marine traffic rules respectively. This system can be recorfigured as a nonlinearity-strengthened one by increasing the number of fuzzy membership functions.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2013.06a
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• pp.493-495
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• 2013

이 연구에서는 울산신항 오일허브 1-2단계 20부두 계획안 중에서 대상선박 20만 DWT급, 30만 DWT급 유조선의 제4항로와 신항 북쪽과 남방파제 사이에서의 교행통항 등에 대하여 최악의 자연환경조건을 설정하여 선박조종 시뮬레이션을 수행하여 선박통항 안전성 평가의 결과에 따른 대상선박 및 항행여건의 개선방안 등에 대하여 제안한 내용을 소개하고자 한다.

• ICROS
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• v.10 no.4
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• pp.35-42
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• 2004

일반적으로 21세기에는 로봇이 기존의 인간이 가지고 있던 작업영역을 대처 할 거라고 말해지고 있으며 가까운 미래에 재난 현장, 인명구조, 지뢰제거, 정찰과 같은 위험작업 영역에 대해서 먼저 기존 인력을 대처할 수 있는 이러한 로봇의 필요성이 두각 되고 있다. 그러나 이러한 위험 작업 현장에서 운영이 가능한 로봇이 만들어지기 위해서는 일차적으로 일반적인 위험작업 지역인 계단과 같은 비 평탄 지형에 대한 이동 성능을 보장할 수 있는 로봇 이동 기술의 개발이 필요하다 일반적으로 이동형 로봇은 Wheel Type, Track Type 그리고 Walking Type으로 구분이 된다. 하지만 비평탄 지역에서 Wheel Type은 Track Type에 비해서 상대적인 주행성능이 떨어진다고 일반적으로 말해지고 있으며 또한 Walking Type은 제어방식이 복잡하고 제어부의 크기가 커서 앞의 두 방식에 비해 절대적으로 이동속도가 느리다는 단점을 가지고 있다. (중략)

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.4
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• pp.1683-1691
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• 2013

Concrete surface grinding is frequently used for flatness of concrete surface, concrete pavement rehabilitation, and adhesiveness in pavement construction. The procedure is, however, labor intensive and has a hazardous work condition. Also, the productivity and the quality of concrete surface grinding highly depend on the skills of worker. Thus, the development of remote controlled concrete surface grinding equipment is necessary to prevent the environmental pollution and to protect the workers from hazardous work condition. However, it is difficult to evaluate the grinded surface objectively in a remote controlled system. Also, The machine vision system developed in this study takes the images of grinded surface with the network camera for image processing. Then, by representing the quality test results to the integrated program of the remote control station, the quality control system is constructed. The machine vision algorithm means the image processing algorithm of grinded concrete surface and this paper presents the objective quality control standard of grinded concrete surface through the application of the suggested algorithm.

• Journal of Navigation and Port Research
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• v.32 no.5
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• pp.321-326
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• 2008

Recently the large sea bridge's construction crossing harbor and main ship's route have been propelled in the domestic so that it is active for the smoothly traffic flow of inland transportation and road user's convenience. However, it can bring about the trouble to ensure marine traffic safety if it is built that sea bridge's construction sets to an economy principle in the extension of the land road system. We're adopting Ship Handling Simulation in representative method for the influence assessment of marine traffic safety and danger elements beforehand. This research attempts to show the problems through the comparison and analysis of the reports relating to the sea bridge construction for 4 organization possessing Ship Handling Simulation. Finally, We offer the necessity of standardization on performing and assessment method of simulations.

• Journal of the Korean Society of Marine Environment & Safety
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• v.30 no.1
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• pp.74-81
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• 2024

In the near future, autonomous ships, ships controlled by shore remote control centers, and ships operated by navigators will coexist and operate the sea together. In the advent of this situation, a method is required to evaluate the safety of the maritime traffic environment. Therefore, in this study, a plan to evaluate the safety of navigation through ship control simulation was proposed in a maritime environment, where ships directly controlled by navigators and autonomous ships coexisted, using autonomous operation technology. Own ship was designed to have autonomous operational functions by learning the MMG model based on the six-DOF motion with the PPO algorithm, an in-depth reinforcement learning technique. The target ship constructed maritime traffic modeling data based on the maritime traffic data of the sea area to be evaluated and designed autonomous operational functions to be implemented in a simulation space. A numerical model was established by collecting date on tide, wave, current, and wind from the maritime meteorological database. A maritime meteorology model was created based on this and designed to reproduce maritime meteorology on the simulator. Finally, the safety evaluation proposed a system that enabled the risk of collision through vessel traffic flow simulation in ship control simulation while maintaining the existing evaluation method.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.38 no.1
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• pp.79-88
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• 2014

Enhancing the working speed and positional accuracy of high-speed press machines is essential for improving the parts accuracy and productivity. However it is known that the positional accuracy decreases and the risk of parts failure increases as the working speed of press machine increases. Therefore predicting such problems during the stage of press structure design is necessary for precise design of high-speed press machines. In the present investigation, the dynamic-elastic deformation of press drive module parts with eccentric masses was examined by finite element analysis and experiment. Then the positional accuracy and parts failure of high-speed press machines was evaluated.

• Proceedings of the Korea Information Processing Society Conference
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• 2018.10a
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• pp.166-169
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• 2018

캐시 부채널 공격 중 하나인 FLUSH+RELOAD 공격은 높은 해상도와 적은 오류로 그 위험성이 높고, 여러가지 프로그램에서도 적용되어 개인정보의 유출에 대한 위험성까지 증명 되었다. 따라서 이 공격을 막기 위해 실시간으로 감지 할 수 있어야 할 필요성이 있다. 본 연구에서는 4가지 실험을 통하여 이 FLUSH+RELOAD 공격을 받을 때 PCM(Performance Counter Monitor)를 사용해 각각의 counter들의 값의 변화를 관찰하여 3가지 중요한 요인에 의해 공격 탐지를 할 수 있다는 것을 발견하였다. 이를 이용하여 머신 러닝의 logistic regression과 ANN(Artificial Neural Network)를 사용해 결과에 대한 각각 학습을 시킨 뒤, 실시간으로 공격에 대한 탐지를 할 수 있는 프로그램을 제작하였다. 일정한 시간동안 공격을 진행하여 모든 공격을 감지하는데 성공하였고, 상대적으로 적은 오탐률을 보여주었다.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2007.11a
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• pp.983-986
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• 2007

Concrete surface grinding is required for flatness and adhesiveness of concrete surface. The procedure is, however, labor intensive and has a hazardous work condition. Also, the productivity and the quality of concrete surface grinding depend on the levels of worker. Thus, the development of remote controlled concrete surface grinding equipment is necessary to prevent the environmental pollution and to protect the workers from hazardous work condition. However, it is difficult to evaluate the grinded surface objectively in a remote controlled system. The machine vision system developed in this study takes the images of grinded surface with the network camera for image processing. Then, by representing the quality test results to the graphic MMI program of the remote control station, the quality control system is constructed. The machine vision algorithm means the image processing algorithm of grinded concrete surface and this paper presents the objective quality control standard of grinded concrete surface through the application of the suggested algorithm.