• 정보처리학회논문지C
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• 제8C권5호
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• pp.557-564
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• 2001

공개 운영체제인 Linux와 FreeBSD는 무료이면서 그 성능이 우수하여 많은 사람들이 사용하고 있다. 개방성은 중요한 특징이지만 공개된 커널의 원천코드는 자주 해커들에 의해서 공격당하는 문제점이 되기도 한다. 본 논문에서는 이러한 문제점을 해결하기에 가장 적합한 해결책인 보안운영체제 SecuROS에 대해서 설명하고, 보안운영체제의 활성화를 돕기 위해 필수적인 표준화된 사용자 및 프로그래머 인터페이스에 대해서 소개한다. 개발된 보안운영체제는 MAC과 ACL 접근통제를 사용하고 가장 일반적으로 사용되고 있는 POSIX 표준을 인터페이스 규격으로 따른다.

• 한국산학기술학회논문지
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• 제14권12호
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• pp.6434-6440
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• 2013

본 논문에서는 관로형 UV 소독기의 자동 세척 제어 및 원격 모니터링이 가능한 통합 제어 시스템을 제안한다. 제안한 시스템은 소독기 내 UV 램프 세척 와이퍼의 다양한 세척 동작 제어가 가능하고 UV 센서를 통해 오염도를 주기적 점검할 수 있어 관로형 소독기를 보다 효율적으로 유지, 보수할 수 있다. 또한, 관로형 소독기의 제어기는 개방형 프로세서를 기반으로 하고 있어 외부의 스마트기기와 블루투스 통신을 통해 제어명령 및 센서 정보 등을 주고받을 수 있다. 그 뿐만 아니라 스마트기기를 통해 무선으로 제어기의 펌웨어 업그레이드가 가능하기 때문에 세척 동작 변화 및 각종 센서 장 탈착에 유연하게 대처할 수 있다. 이러한 장점들을 통해 제안한 시스템으로 소규모 마을 등의 스마트 하수 처리 시스템 구축이 가능하다.

• Journal of Information Processing Systems
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• 제17권6호
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• pp.1071-1082
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• 2021

Since the smart factory has been recently recognized as an industrial core requirement, various mechanisms to ensure efficient and stable operation have attracted much attention. This attention is based on the fact that in a smart factory environment where operating processes, such as facility control, data collection, and decision making are automated, the disruption of processes due to problems such as facility anomalies causes considerable losses. Although many studies have considered methods to prevent such losses, few have investigated how to effectively apply the solutions. This study proposes a Kubernetes based system applied in a smart factory providing effective operation and facility management. To develop the system, we employed a useful and popular open source project, and adopted deep learning based anomaly detection model for multi-sensor anomaly detection. This can be easily modified without interruption by changing the container image for inference. Through experiments, we have verified that the proposed method can provide system stability through nondisruptive maintenance, monitoring and non-disruptive updates for anomaly detection models.

• Journal of Power Electronics
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• 제13권4호
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• pp.679-691
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• 2013

High-power electromagnetic transmitter power supplies are an important part of deep geophysical exploration equipment. This is especially true in complex environments, where the ability to produce a highly accurate and stable output and safety through redundancy have become the key issues in the design of high-power electromagnetic transmitter power supplies. To solve these issues, a high-frequency switching power cascade based emission power supply is designed. By combining the circuit averaged model and the equivalent controlled source method, a modular mathematical model is established with the on-state loss and transformer induction loss being taken into account. A triple-loop control including an inner current loop, an outer voltage loop and a load current forward feedback, and a digitalized voltage/current sharing control method are proposed for the realization of the rapid, stable and highly accurate output of the system. By using a new algorithm referred to as GAPSO, which integrates a genetic algorithm and a particle swarm algorithm, the parameters of the controller are tuned. A multi-module cascade helps to achieve system redundancy. A simulation analysis of the open-loop system proves the accuracy of the established system and provides a better reflection of the characteristics of the power supply. A parameter tuning simulation proves the effectiveness of the GAPSO algorithm. A closed-loop simulation of the system and field geological exploration experiments demonstrate the effectiveness of the control method. This ensures both the system's excellent stability and the output's accuracy. It also ensures the accuracy of the established mathematical model as well as its ability to meet the requirements of practical field deep exploration.

• 디지털융복합연구
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• 제19권2호
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• pp.245-251
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• 2021

1,2인 가구가 꾸준하게 늘어나고 있는 추세에 비어 있는 시간대에 집을 방문하는 외부인이 누구인지 확인하고 싶은 요구가 증가하고 있다. 얼굴인식 기술은 많은 연구를 통해 여러 가지 모델이 제안되었는데 OpenCV의 Harr Cascade와 Dlib의 Hog가 대표적인 오픈소스 모델이다. 두 모델은 사용 환경에 따른 장단점을 가지고 있는데, 본 연구에서 초점을 둔 실내 현관 앞과 제한된 거리에서는 Dlib의 Hog가 강점을 가진다. 본 논문에서는 딥러닝 오픈 소스인 Dlib에 기반을 둔 얼굴인식 방문자 출입관리 시스템을 설계하고 구현하였다. 전체 시스템은 프론트 모듈과 서버모듈, 모바일모듈로 구성되며 세부적으로는 얼굴등록, 얼굴인식, 실시간 방문자 확인 및 원격제어, 동영상 저장 기능을 포함한다. 인터넷에서 공개된 사진을 이용하여 거리임계 값의 변화에 따른 정밀도, 특이도, 정확도를 구하고 선행연구 결과와 비교하였다. 실험 결과 구현된 시스템이 정상적으로 동작하는 것을 확인 하였으며 Dlib에서 보고한 것과 비슷한 결과를 보이는 것을 확인 하였다.

• 제어로봇시스템학회논문지
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• 제21권2호
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• pp.87-94
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• 2015

This paper proposes a situation awareness method based on data fusion and independent objects for autonomous driving in on-road environment. The proposed method, designed to achieve an accurate analysis of driving situations in on-road environment, executes preprocessing tasks that include coordinate transformations, data filtering, and data fusion and independent object based situation assessment to evaluate the collision risks of driving situations and calculate a desired velocity. The method was implemented in an open-source robot operating system called ROS and tested on a closed road with other vehicles. It performed successfully in several scenarios similar to a real road environment.

• 대한의용생체공학회:의공학회지
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• 제15권3호
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• pp.355-364
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• 1994

The most important requirement for the controller of a prosthetic arm is that it has a high fidelity discriminator where the motion control may be performed open loop using EMG signals as a control source. Therefore, it is very effective method to reduce the influence of misclassification of classifier for the total system performance. This paper presents the new function discrimination method which combines MLP classifier and frizzy filter by stages for the requirement. The major advantage of MLP is a consistent learning capability for the easy adaptation to environments. The fuzzy filter uses all informations of MLP outputs and prior EMG activity informations which increase as the experience increases. That property is superior to one which uses maximum output of MLP in view of information amounts and quality. Simulation result shows that proposed method is superior to the probabilistic model, MLP model and the combined model of both in the respect of discrimination quaity.

• 한국컴퓨터정보학회논문지
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• 제24권3호
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• pp.151-157
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• 2019

In this paper, we present a prototype system for controlling IoT home appliances via voice-based commands. A voice command has been widely deployed as one of unobtrusive user interfaces for applications in a variety of IoT domains. However, interoperability between diverse IoT systems is limited by several dominant companies providing voice assistants like Amazon Alexa or Google Now due to their proprietary systems. A global IoT standard, oneM2M has been proposed to mitigate the lack of interoperability between IoT systems. In this paper, we deployed oneM2M-based platforms for a voice record device like a wrist band and LED control device like a home appliance. We developed all the components for recording voices and controlling IoT devices, and demonstrate the feasibility of our proposed method based on oneM2M platforms and Google STT (Speech-to-Text) API for controlling home appliances by showing a user scenario for turning the LED device on and off via voice commands.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2008년도 추계학술대회 논문집
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• pp.229-234
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• 2008

The new millennium has started with several innovations driven by fast evolution of the technologies in energy sector. A strong impulse towards the diffusion of new economical efficient technologies regulatory incentives related to energy production from renewable source and a small scale building trigeneration and to promotion of more sustainable environmental-friendly generation solutions, the evolution of electricity markets, more and more binding local emission constraints, and the need for improving the security of supply to reduce the energy system vulnerability. The 24 percentage energy quantify of total energy consumption consumes in commercial buildings and residential houses and the 30% portion of total $CO_2$ emissions covers also in the commercial buildings and residential houses sector. To cope with efficiently this energy sinuation in building sector, Building microgrid or building tooling, heating & power(BCHP) system has been interested in recent day due to meeting thermal and electric energy requirements efficiently and with appropriate energy quality. A multi agent system is a collective of intelligent agents that communicate with each other and work cooperatively to achieve common goals. Also, it is to medicate and coordinate communication between Control Areas and Security Coordinators for teal-time control of the BCHP system and the power pid. In this new circumstance, it is very important to integrate the power and energy delivery system and the information system(communication, networks, and intelligent equipment) that controls it. Therefore, development of smart control modules with open communication protocol and seamlessly interchange the data and information between control network and data network including extranet and intranet give a great meanings. We designed and developed the TCP/IP-CAN IED agent modules and ModBus./LonTalk/(TCP/IP) IED agent ones to configure the multi-agent system based smart energy network of commercial buildings and also intelligent algorithms for inverter fault diagnostics which ran be operated in control level or agent level network.

• 한국산업보건학회지
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• 제16권3호
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• pp.290-301
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• 2006

A push pull hood system is frequently applied to control contaminants evaporated from an open surface tank. Efficiency of push pull hood system is affected by various parameters, such as, cross draft, vessel shapes, tank surface area, liquid temperature. A previous work assisted by flow visualization technique qualitatively showed that a strong cross draft blown from the pull hood to push slot could destroy a stable wall-jet on the surface of tank, resulting in the abrupt escape of smoke from the surface. In this study, the tracer gas method was applied to determine the effect of cross-draft on the capture efficiency qualitatively. A new concept of capture efficiency was introduced, that is, linear efficiency. This can be determined by measuring the mass of tracer gas in the duct of pull hood while the linear tracer source is in between push slot and pull hood. By traversing the linear tracer source from the push slot to the pull hood, it can be found where the contaminant is escaped from the tank. Total capture efficiency can be determined by averaging the linear efficiencies. Under the condition of cross-draft velocities of 0, 0.4, 0.75, 1.05 and 1.47m/s, total capture efficiencies were measured as 97.6, 95.4, 94.6, 92.7 and 70.5% respectively. The abrupt reduction of efficiency with cross-draft velocity of 1.47m/s was due to the destruction of tank surface wall-jet by the counter-current cross-draft. The same phenomenon was observed in the previous flow visualization study. As an alternative to overcome this abrupt efficiency drop, the 20% increase of hood flow rates was tested, resulting in 20% efficiency increase.