준실시간 품질처리 기법을 활용한 해수위 관측자료의 품질개선 방안

석민준,황창수,이수호,이준식,송동훈,박상표 한국수로학회 2023 한국수로학회지 Vol.12 No.2

립해양조사원(KHOA, Korea Hydrographic and Oceanographic Agency)은 국가해양관측망의 안정적인 운영과 해양관측자료의 품질 향상을 위하여 관측시설물 유지관리와 해양관측자료의 품질처리(실시간 및 비실시간)를 수행하고 있다. 실시간 품질처리는 다양한 물리적 알고리즘 및 기준을 이용하여 자동 품질처리를 수행하는 것으로, 실시간 품질처리가 완료된 관측자료는 ‘국립해양조사원 홈페이지 누리집’을 통해 제공 중이다. 비실시간 품질처리는 매월 초순에 전월의 관측자료를 대상으로 품질관리 담당자가 수동 품질처리를 수행하는 것이며, 비실시간 품질처리가 완료된 자료는 가공 및 분석을 통해 통계 자료, 1시간 조위 등을 산출하여 해당 정보들을 간행물에서 제공하고 있다. 본 연구는 국내 해양관측자료의 품질처리 방법 개선을 위하여 기존 실시간, 비실시간 품질처리 기법 외 적용이 가능한 준실시간 품질처리 기법을 조사하고, 해당 기법을 해수위 관측자료에 적용 및 실험하여 활용 가능성을 검토하였다. 해양관측자료 준실시간 품질처리 기법의 조사 결과, 다양한 해양과 관련된 국제적인 유관기관(IOC, GLOSS 등)에서는 해수위(조위) 관측자료의 품질개선을 위해 SELENE(SEa LEvel NEar-real time quality control processing) 알고리즘의 적용을 적극 권장하고 있다. 이에 국립해양조사원의 조위관측소에서 수집한 조위 자료에 대해 품질처리 최적화 실험을 통해 적합한 매개변수를 산출하였으며, 해당 기법을 적용하여 품질처리 정확도를 분석하였다. 분석 결과, 특이상황을 제외한 조위 관측자료의 준실시간 품질처리 정확도는 평균 90% 이상으로 매우 양호하게 나타났다. 따라서 실시간 및 비실시간 품질검사 외 해당 준실시간 품질처리 기법을 품질검사 현업에 도입·적용한다면, 조위 관측자료의 품질개선과 더불어 신속한 품질처리 자료 생산으로 해양정보 서비스 활용도 향상에 큰 도움이 될 것으로 생각된다. The main responsibility of Korea Hydrographic and Oceanographic Agency (KHOA) is to operate the Korea Ocean Observing and Forecasting System(KOOFS) and enhance the quality of observed oceanographic data. To achieve this, KHOA maintains facilities and quality control of observed oceanographic data in real-time and non-real time. real-time quality control means automatic quality control using various physical algorithms. The data for which real-time quality control has been completed is provided on the the KHOA Homepage. Non-real time quality control means manual processing by oceanographic experts.statistical data, hourly tidal levels, and other information, which is made available through publications. The purpose of study is to enhance the quality processing performance of marine observation data by applying near-real time quality control techniques in addition to the existing quality control methods. First, a survey was conducted on the various quality processing techniques used by various international organizations. And then, among the surveyed techniques, suitable methods were applied to sea level data for experimentation. According to the results of the investigation into near-real time quality management technology, various institutions strongly recommend the use of the SELENE(SEa LEvel NEar-real time quality control processing) algorithm for improving the quality of sea level data. To determine suitable parameters, optimization experiments were conducted using sea level data observed at KHOA's tidal observation station. This algorithm was then utilized to measure the accuracy of quality control data. As a result, the accuracy of near-real time quality-managed sea level data except in special situation was found to be above 90% on average. If it would use the near-real time quality management technique and utilizing it in conjunction with real-time and non-real time quality management would not only enhance the quality of sea level observation data but also enable swift quality management. Therefore, it is expected to significantly contribute to the improvement of marine information services.

오픈 소스 소프트웨어를 이용한 실시간 모션 제어기의 설계 및 구현

김익환(Ikhwan Kim),박수용(Sooyong Park),성민영(Minyoung Sung),김태현(Taehyoun Kim) 한국정보과학회 2012 정보과학회논문지 : 시스템 및 이론 Vol.39 No.2

다중 모터로 구성된 고정밀 동기 모션 제어 시스템은 다양한 산업 분야에 사용되고 있다. 모션제어기는 기본적으로 시스템을 구성하는 모터 드라이브들에게 정해진 시간 내에 주기적으로 제어 명령을 전달할 수 있어야 하고 드라이브 장치간의 정밀한 동기화를 지원해야 하며, 시스템의 원격 감시 및 제어와 같은 관리의 편의성도 제공하여야 한다. 실시간 이더넷 통신 기술은 이러한 요구사항을 쉽게 만족시킬 수 있는 여러 가지 장점을 가지고 있다. 한편, 모션 제어 응용 분야에서 또 다른 중요한 경향은 개방성 지원이다. 산업용 제어 응용 시장의 확대를 위해서는 각 제조사 솔루션간의 호환성 확보 문제와 확장 가능성 제한 문제를 해결하기 위한 개방형 프로그래밍 표준의 지원이 필수적이다. 본 논문에서는 산업용 제어 프로그래밍 표준을 지원하는 오픈 소스 통합 개발환경을 확장하여 대표적인 실시간 이더넷 기술 중 하나인 EtherCAT을 지원하는 실시간 모션 제어기를 구현하였다. 구현된 모션 제어기는 응용 프로그램 작성, EtherCAT 네트워크 관리, 실시간 EtherCAT 통신을 지원하는 런타임 등을 포괄하는 통합 개발환경을 제공한다. 구현된 실시간 동기 모션 제어기의 성능 평가를 위해 범용 리눅스 및 Xenomai 환경에서 태스크 활성화 주기의 지터와 태스크 응답시간을 측정하고 그 결과를 분석하였다. 실험 결과 범용 리눅스 환경은 10 ms 이상의 제어주기를 갖는 비교적 낮은 정밀도의 모션 제어에 적합한 반면, Xenomai 환경은 1 ms 이하의 제어주기를 요구하는 고정밀 모션 제어에도 큰 무리 없이 사용할 수 있음을 확인할 수 있었다. Recently, high-precision synchronous motion control systems with multi-motor actuation are widely deployed in various industry fields. The primary requirement for motion control systems is real-time periodic control and precise synchronization between motor drives. They also need system management functions such as remote monitoring and control. Considering those requirements, Real-time Ethernet (RTE) technologies can offer many advantages for motion control applications. Another important trend in motion control application is openness. To resolve compatibility issues among different products from various vendors and limitation of scalability, it is essential to support the open standards for programming industrial control systems. In this paper, we designed and implemented a real-time synchronous motion controller with EtherCAT support by extending an open source IDE (Integrated Development Environment) for standardized industrial automation platforms. Our system provides application programming environment, EtherCAT network management, automatic code generation, and real-time data communication through EtherCAT network in a single IDE. We also measured and analyzed task release time jitter and task response time on legacy Linux kernel and Xenomai real-time extension. The result show that Xenomai can support high-precision motion control of which cycle time is under 1 ms while legacy Linux kernel can only provide deterministic performance for low-precision motion control of which cycle time is higher than 10 ms

A novel real-time method for HVAC system operation to improve indoor environmental quality in meeting rooms

Li, Wenzhuo,Koo, Choongwan,Cha, Seung Hyun,Hong, Taehoon,Oh, Jeongyoon Elsevier 2018 Building and Environment Vol.144 No.-

<P><B>Abstract</B></P> <P>For indoor environmental quality (IEQ), previous studies only focused on one-sided aspect (e.g. monitoring, diagnostic, or intervention), and have not fully considered excessive pollutants and dew condensation in meeting rooms. Based on a real-time sensor network, this study newly implemented a three-phase cyclic process (i.e. monitoring-diagnostic-intervention process), with which a novel real-time method for HVAC system operation was developed to improve IEQ in meeting rooms. In particular, this study conducted two kinds of analyses and controls: (i) basic analysis and control for excessive pollutants by utilizing temperature and CO<SUB>2</SUB> concentration; and (ii) advanced analysis and control for dew condensation on the diffuser of HVAC system by utilizing temperature, humidity, and CO<SUB>2</SUB> concentration. The main findings were summarized as follows. For the 'basic analysis', the CO<SUB>2</SUB> concentration was estimated to exceed 1000 ppm at 14.8% and 31.7% in two meeting rooms. To avoid it, a real-time 'basic control' strategy was developed: if the CO<SUB>2</SUB> concentration would exceed 1000 ppm, the ventilation volume of the outdoor air could increase in real time. For the 'advanced analysis', dew condensation on the diffuser was estimated to happen at 40.7% and 82.6% in two meeting rooms. To avoid it, a real-time 'advanced control' strategy was developed: if the estimated supply air temperature would be lower than the calculated dew-point temperature, the supply-air temperature and ventilation volume of HVAC system could increase. The novel real-time method can be easily applied to HVAC system operation in existing buildings where events are hard to be predicted and recognized.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A novel real-time automatic control method for HVAC system operation was proposed. </LI> <LI> A three-phase cyclic process (monitoring-diagnostic-intervention) was implemented. </LI> <LI> A basic strategy was proposed for a real-time removal of excessive pollutant (CO<SUB>2</SUB>). </LI> <LI> An advanced strategy was proposed for a real-time prevention of dew condensation. </LI> <LI> The proposed method is expected to significantly improve the IEQ in meeting rooms. </LI> </UL> </P>

A study on Real-Time Implementation of Robust Control for Horizontal Articulated Arm with Eight Axis

Hoo-Cong Nguyen(노연 후 콩),Jun-Hong Kim(김준홍),Hee-Seop Lee(이희섭) 한국산업융합학회 2015 한국산업융합학회 논문집 Vol.18 No.3

In this paper, we describe a new approach to perform real-time implementation of an robust controller for robotic manipulator based on digital signal processors in this paper. The Texas Instruments DSPs chips are used in implementing real-time adaptive control algorithms to provide enhanced motion control performance for dual-arm robotic manipulators. In the proposed scheme, adaptation laws are derived from model reference adaptive control principle based on the improved direct Lyapunov method. The proposed adaptive controller consists of an adaptive feed-forward and feedback controller and time-varying auxiliary controller elements. The proposed control scheme is simple in structure, fast in computation, and suitable for real-time control. Moreover, this scheme does not require any accurate dynamic modeling, nor values of manipulator parameters and payload. Performance of the proposed adaptive controller is illustrated by simulation and experimental results for robot manipulator consisting of dual arm with eight degrees of freedom at the joint space and cartesian space.

연동교차로를 위한 통행시간기반 신호제어 알고리즘의 현장 적용 및 평가

정영제,김영찬 대한교통학회 2009 대한교통학회지 Vol.27 No.5

This study develops a real-time signal control algorithm based on sectional travel times and includes a field test and evaluation. The objective function of the signal control algorithm is the equalization of delay of traffic movements, and the main process is calculating dissolved time of the queue and delay using the sectional travel time and detection time of individual vehicles. Then this algorithm calculates the delay variation and a targeted red time and calculates the length of the cycle and phase. A progression factor from the US HCM was applied as a method to consider the effect of coordinating the delay calculation, and this algorithm uses the average delay and detection time of probe vehicles, which were collected during the accumulated cycle for a stabile signal control. As a result of the field test and evaluation through the application of the traffic signal control algorithm on four consecutive intersections at 400m intervals, reduction of delay and an equalization effect of delay against TOD control were confirmed using the standard deviation of delay by traffic movements. This study was conducted to develop a real-time traffic signal control algorithm based on sectional travel time, using general-purpose traffic information detectors. With the current practice of disseminating ubiquitous technology, the aim of this study was a fundamental change of the traffic signal control method. 본 연구에서는 구간통행시간을 기반으로 하는 실시간 교통신호제어 알고리즘을 개발하였으며, 알고리즘의 현장 실험 및 평가를 수행하였다. 구간통행시간 기반 실시간 신호제어 알고리즘은 전체 접근로의 지체 균등화를 목적함수로 하며, 주요 과정으로는 개별차량 지체와 차량관측 시간을 이용한 대기행렬 해소시간의 산정과 이를 기반으로 교차로 지체를 산정하는 과정이다. 이후 이동류별 주기단위 지체변화량을 산정하고, 주기 결정 및 현시 배분 등의 과정이 이루어진다. 이동류별 지체의 산정과정에서는 연동교차로의 특성을 고려하여 HCM의 연동계수를 이용한 독립교차로에서의 지체로 환산하는 과정을 수행하며, 이때 누적주기의 프르브 차량 정보를 이용함으로써 보다 안정적 신호제어를 도모하였다. 통행시간 기반 신호제어 알고리즘의 현장실험 및 평가를 통해 TOD 제어와의 비교평가를 수행하였으며, 실험대상 가로축은 약 400m의 평균 교차로 간격을 가지는 일련의 4개 교차로로 구성되어 있다. 현장실험 및 평가 결과 TOD 제어 대비 지체 감소 효과와 더불어 이동류별 지체의 표준편차 감소를 통해 지체의 균등화 효과를 확인하였다. 본 연구를 통해 교통정보수집을 위한 범용의 검지체계에서 산출되는 개별차량의 구간통행시간 정보를 기반으로 하는 실시간 신호제어 알고리즘의 개발 및 평가를 수행하였으며, 이는 유비쿼터스 환경의 급속한 확산이라는 교통환경의 변화에 부응하기 위한 신호제어 방법론의 근본적인 변화에 궁극적인 목표를 두고 있다.

Adaptive Intelligent Sensing Control Method for Traffic Lights under Real-Time Vehicle Conditions Based on Logic Rules

Yang Liu,Jiaojiao He,Jingwei Chen,Bo Mi,Ling Zhao,Xinyu Liu,Linhan Yang 한국인터넷정보학회 2024 KSII Transactions on Internet and Information Syst Vol.18 No.12

Compared with traditional adaptive algorithms, the complex and changing operating environment of intelligent networks demands high real-time accuracy in data transmission, necessitating an accurate and adaptive traffic light control strategy. Machine learning (ML) techniques can predict traffic conditions based on historical data and real-time information. However, some scholars have mentioned that ML techniques are still deficient in real-time response and in coping with random traffic accidents. Traditional Reinforcement Learning (RL) requires repeated trial and error operations. Applying traditional RL techniques to the optimal control of traffic lights may lead to more serious traffic congestion in some cases. Therefore, this paper combines perceptual control with real-time adaptive control methods to provide a rule-based reasoning method for adaptive intelligent perception and precise control of traffic signals under real-time smart grid-connected hybrid vehicle conditions. IIoT (Industrial Internet of Things) devices are utilized to monitor the parking queue length, pedestrian flow, vehicle flow, and traffic flow in each lane in real time to dynamically adjust the green light duration. By adjusting the light priority according to real-time vehicle and road conditions, this method solves the problem of wasting green lights when random accidents occur in a certain lane, optimizes traffic light settings, achieves real-time precise control of lane flow, and improves the adaptability and precision of traffic lights.

Development of a real-time drying control system for a pneumatic conveying dryer for sawdust in pellet production

Euh, Seung Hee,Choi, Yun Sung,Nam, Yun Sung,Lee, Chung Gun,Lee, Sang Yeol,Oh, Kwang Cheol,Oh, Jae Heun,Kim, Dae Hyun Elsevier 2018 ENERGY Vol.161 No.-

<P><B>Abstract</B></P> <P>This study presents a real-time drying control system that was developed to control air drying of sawdust in a pneumatic conveying dryer to produce high-grade wood pellets in the range of the target moisture content (MC). The real-time drying control system was installed with moisture sensors to control the ON/OFF periods of the fuel (pellet) supply motor for the sawdust to generate the heat necessary to dry the sawdust to an optimum level of 15% moisture content for pelletizing. The results of the experiment and the simulation showed that the drying efficiency improved when a buffer was introduced instead of using a conventional system, and the average moisture content of the dried sawdust was measured to be about 12.4% in a pneumatic conveying dryer without buffer and about 14.7%–15.2% in the developed real-time drying control system. This study shows that the real-time drying control system could dry the sawdust to the targeted constant moisture content, and the buffer in the pneumatic conveying dryer could improve the drying efficiency according to an increase in the resident time of the sawdust.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A real-time drying control system was developed to control the air drying process for sawdust in a pneumatic conveying dryer. </LI> <LI> Drying efficiency was improved when the buffer was present instead of the conventional system. </LI> <LI> The real-time drying control system dries the sawdust with constant range compared to the initial moisture content. </LI> </UL> </P>

유전자 알고리듬을 이용한 지능구조물의 PPF 제어기 실시간 다중변수 조정

허석,곽문규 한국소음진동공학회 2001 소음 진동 Vol.11 No.1

This paper is concerned with the real-time automatic tuning of the multi-input multi-output positive position feedback controllers for smart structures by the genetic algorithms. The genetic algorithms have proven its effectiveness in searching optimal design parameters without falling into local minimums thus rendering globally optimal solutions. The previous real-time algorithm that tunes a single control parameter is extended to tune more parameters of the MIMO PPF controller. We employ the MIMO PPF controller since it can enhance the damping value of a target mode without affecting other modes if tuned properly. Hence, the traditional positive position feedback controller can be used in adaptive fashion in real time. The final form of the MIMO PPF controller results in the centralized control, thus it involves many parameters. The bounds of the control Parameters are estimated from the theoretical model to guarantee the stability. As in the previous research, the digital MIMO PPF control law is downloaded to the DSP chip and a main program, which runs genetic algorithms in real time, updates the parameters of the controller in real time. The experimental frequency response results show that the MIMO PPF controller tuned by GA gives better performance than the theoretically designed PPF. The time response also shows that the GA tuned MIMO PPF controller can suppress vibrations very well.

Real-Time Feasible Nonlinear Model Predictive Control for Waypoint Following of a Chain-Based Mobile Robot

Hamza Hobbani,Fernando Perez-Peña,Karsten Schmidt 제어·로봇·시스템학회 2026 International Journal of Control, Automation, and Vol.24 No.5

In this paper, a real-time nonlinear model predictive control (NMPC) approach is proposed for high-precision waypoint following in mobile robotswith chain-based drive systems. The NMPC-based control setup profits from predictive capabilities and adeptness at handling constraints to deal with the challenges of multi-constrained control problems. An extended Kalman filter (EKF) is integrated into the system framework to achieve real-time estimation for unobservable system states and noisy velocity measurements, thereby enhancing the robustness of the feedback loop. The proposed approach is compared with heuristic methods such as pure pursuit (PP), multi-goal stabilization (MGS), classical sliding mode control (SMC), as well as a standard NMPC formulation with terminal cost (T-NMPC) to showcase improvements in waypoint following performance, disturbance rejection, and time-varying constraints. Based on hardware tests, an extensive real-time feasibility analysis is presented, which is essential for assessing the suitability of the approach for execution on the target hardware platform. The NMPC framework demonstrates improved waypoint following, robustness, and error minimization through MATLAB/Simulink simulations with adaptive variation to operating conditions. The robustness ofNMPCis further confirmed through extensive experiments on a real chain-based mobile robot platform developed under ROS2 as a software framework, where R2 values reached up to 68.18% in simulations and 62.01% in real-world experiments, compared to 51.42% and 57.54% obtained with PP. Stress-testing in the real-time feasibility analysis showed a runtime of approximately 50 ms on target hardware, while the nested-NMPC (N-NMPC) variant achieved runtimes of around 20 ms in real-world experiments due to warm-starting of the optimizer. These findings confirm NMPC as a benchmark in model-based approaches for achieving higher accuracy and control in waypoint following of chain-based robots, thereby contributing to future directions of research in this area.

Validation of model-based adaptive control method for real-time hybrid simulation

Guoshan Xu,Xizhan Ning,Wei Huang,Zhen Wang,Lichang Zheng 국제구조공학회 2023 Smart Structures and Systems, An International Jou Vol.31 No.3

Real-time hybrid simulation (RTHS) is an effective experimental technique for structural dynamic assessment. However, time delay causes displacement de-synchronization at the interface between the numerical and physical substructures, negatively affecting the accuracy and stability of RTHS. To this end, the authors have proposed a model-based adaptive control strategy with a Kalman filter (MAC-KF). In the proposed method, the time delay is mainly mitigated by a parameterized feedforward controller, which is designed using the discrete inverse model of the control plant and adjusted using the KF based on the displacement command and measurement. A feedback controller is employed to improve the robustness of the controller. The objective of this study is to further validate the power of dealing with a nonlinear control plant and to investigate the potential challenges of the proposed method through actual experiments. In particular, the effect of the order of the feedforward controller on tracking performance was numerically investigated using a nonlinear control plant; a series of actual RTHS of a frame structure equipped with a magnetorheological damper was performed using the proposed method. The findings reveal significant improvement in tracking accuracy, demonstrating that the proposed method effectively suppresses the time delay in RTHS. In addition, the parameters of the control plant are timely updated, indicating that it is feasible to estimate the control plant parameter by KF. The order of the feedforward controller has a limited effect on the control performance of the MAC-KF method, and the feedback controller is beneficial to promote the accuracy of RTHS.