• Journal of Korean Society on Water Environment
• /
• v.36 no.6
• /
• pp.535-545
• /
• 2020

This study aims to conserve and monitor energy use in public sewage treatment plants by utilizing data from the SCADA system and by controlling the aeration rate required for maintaining effluent water quality. Power consumption in the sewage treatment process was predicted using the equipment's uptime, efficiency, and inherent power consumption. The predicted energy consumption was calibrated by measured data. Additionally, energy efficiency indicators were proposed based on statistical data for energy use, capacity, and effluent quality. In one case study, a sewage treatment plant operated via the SBR process used ~30% of energy consumed in maintaining the bioreactors and treated water tanks (included decanting pump and cleaning systems). Energy consumption analysis with the K-ECO Tool-kit was conducted for unit processing. The results showed that about 58.7% of total energy consumed was used in the preliminary and biological treatment rotating equipment such as the blower and pump. In addition, the energy consumption rate was higher to the order of 19.2% in the phosphorus removal process, 16.0% during sludge treatment, and 6.1% during disinfection and discharge. In terms of equipment energy usage, feeding and decanting pumps accounted for 40% of total energy consumed following 27% for blowers. By controlling the aeration rate based on the proposed feedback control system, the DO concentration was reduced by 56% compared pre-controls and the aeration amount decreased by 28%. The overall power consumption of the plant was reduced by 6% via aeration control.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.28 no.6
• /
• pp.937-945
• /
• 2022

Maritime autonomous surface ships (MASS) have a high degree of autonomy and operate autonomously along a planned route. However, when necessary, the shore remote control center(SRCC) can directly intervene in ship operations. In this paper, the operation concept of the simulator system, which can be used to educate and train shore remote control officers, responsible for monitoring the operation of autonomous ships on land and remotely controlling them in case of an emergency, is reviewed. The required functions of the simulator system that enables the operation concept are also reviewed. The major parts of the SRCC simulator system are the monitoring station and control station, which simulate the functions of monitoring the operation status of multiple MASS and the functions of the remote operation of MASS in the case of emergency, respectively. Various units to simulate the operation of MASS and traf ic ships and various objects around the MASS are included in the simulator system. The instructor operation station is the central part of the simulator system that integrates and controls the unit systems. Functionally, as conditions under which SRCC is allowed to remotely intervene in the operation of MASS, the emergency situation for remote control (ESRC) has been defined. Moreover, the required functions to cope with these ESRC conditions have been included in the simulator system requirements.

• Journal of the Institute of Electronics Engineers of Korea CI
• /
• v.47 no.6
• /
• pp.93-102
• /
• 2010

Existing web based information service system solutions show limitations in mobile information services, as well as problems such as uncertain error messages, and difficulty providing swift assistance or real time emergency support. In order to solve these deficiencies, a realtime wireless remote control system has been designed and implemented in this thesis, which is capable of managing and monitoring remote systems using mobile communication devices (Mobile Phone, PDA, Smart Phone) for realtime control. Proposed systems are applied at remote places, for instance 'office building', and a nursery school like 'kindergarten'. In the case of implemented at office building, it can be managing and controlling at real time all sorts of the sensor information that are installed at office building system environment through wire(web environment) or wireless(mobile device). In the other case at kindergarten system that are providing the real-time wireless remote control and monitoring system can be monitoring activity of kindergarten children with a mobile phone of authentication user. The security functions of proposed systems include mobile device user authentication and target system access control. The proposed systems allow real-time user authentication function and system access control function that improve the security of resource administrators and mobile device users, and provides not only uninterrupted services, but also real time mobile service environments.

• Journal of Soil and Groundwater Environment
• /
• v.15 no.6
• /
• pp.17-28
• /
• 2010

As a preliminary survey to improve efficiency of well-based permeable reactive barrier system for groundwater remediation, this site-scale study was carried to identify the flowpaths and controlling factors of plume at a remediation site in Suwon City, Korea. A total of 22 monitoring wells were installed as a grid system in the $4m{\times}4m$ square area by 1-m interval. For the groundwater characterization, various tests were performed including water-level monitoring, water sampling & analysis, pumping and slug tests, and tracer tests. The aquifer appeared to be unconfined with hydraulic conductivities (K) ranging from $2.6{\times}10^{-4}cm/s$ to $9.5{\times}10^{-3}cm/s$. The average linear velocity of groundwater was estimated to be $2.94{\times}10^{-6}m/s$, and the longitudinal dispersivity of a conservative tracer to be $5.94{\times}10^{-7}m^2/s$. Groundwater plume moves preferentially through the high-K zones, and the relatively high ion concentrations along the low-K zones implying deterred groundwater flow. Consequently, the spatial variation of hydraulic conductivity caused by aquifer heterogeneity and anisotropy appears to be the most important factor to maximize the effect of plume treatment system for application of in-situ groundwater remediation techniques.

• Geomechanics and Engineering
• /
• v.30 no.2
• /
• pp.187-199
• /
• 2022

Kriging metamodel, as a flexible machine learning method for approximating deterministic analysis models of an engineering system, has been widely used for efficiently estimating slope reliability in recent years. However, the autocorrelation function (ACF), a key input to Kriging that affects the accuracy of reliability estimation, is usually selected based on empiricism. This paper proposes an adaption of the Kriging method, named as Genetic Algorithm optimized Whittle-Matérn Kriging (GAWMK), for addressing this issue. The non-classical two-parameter Whittle-Matérn (WM) function, which can represent different ACFs in the Matérn family by controlling a smoothness parameter, is adopted in GAWMK to avoid subjectively selecting ACFs. The genetic algorithm is used to optimize the WM model to adaptively select the optimal autocorrelation structure of the GAWMK model. Monte Carlo simulation is then performed based on GAWMK for a subsequent slope reliability analysis. Applications to one explicit analytical example and two slope examples are presented to illustrate and validate the proposed method. It is found that reliability results estimated by the Kriging models using randomly chosen ACFs might be biased. The proposed method performs reasonably well in slope reliability estimation.

• 제어로봇시스템학회:학술대회논문집
• /
• 2004.08a
• /
• pp.346-349
• /
• 2004

The teleoperation system applies all of the industrial fields due to the development of the network infrastructure. It is one of the indispensable elements for controlling the robot at a remote sight and monitoring the limit or unknown environment. The common teleoperation robot system is what has the visual module to supply the network system and realistic UI to the existed robot system. Therefore, remarked that the fusion between modules and transmission of visual data the remarked the important element to improve the robot application in the various environments. Delay of development time by robot platform and noneffective communication among developers are also problem to approach. In this paper we propose the independent teleoperation system. The main application language is JAVA in this system, which is applied JAVA API like JNI and JMF to construct the effective teleoperation system. The system has the both side communication system between sever and client as a basic structure. The visual data that is attached the robot at a remote sight is captured by JMF API and then is transmitted to the web browser called client by RTR protocol. JNI is used to connect between JAVA and the lower part application (sensor fusion, motion control.) of the robot programmed by various Native languages. The proposed system is the application that can perform the elements, for instance transmission of visual data, the fusion of various native application modules and the effective network communication, with any platform.

• Journal of IKEEE
• /
• v.22 no.4
• /
• pp.959-964
• /
• 2018

In this study, a study is conducted on a monitoring system that can control the environment of plants using sensors in conjunction with the LED light system and the plant growth control system. To verify the performance of the developed plant growth system, an experiment was conducted on the characteristics of energy efficiency, data transmission rate, and light volume control. The experiment resulted in a satisfactory result by controlling more than 80% energy efficiency, 1Mb/sec wireless communication speed, and 5 levels of optical control. The proposed system can be applied to LED plant facilities and will contribute to the automation of agriculture by organizing an automated system for production efficiency and labor cost reduction for future commercialization.

• Journal of Korean Society on Water Environment
• /
• v.35 no.1
• /
• pp.55-63
• /
• 2019

The Four Major Rivers Restoration Project started in 2009 and completed in early 2013 is a large-scale inter-ministry SOC project investing ₩22.2 $10^{12}$ and one of the Project's objectives was to enhance the water-quality grade through recovering the river eco-system and environment. The average concentration and probability distribution of water-quality constituents at given and selected sampling sites are very significant elements for analyzing and controlling the water-quality of rivers or reservoirs effectively. Average concentration can be estimated by point estimator, distribution function of water-quality constituents or Bootstrap method, in which the distribution function estimated with more data in case of insufficient dataset, is applied. Ipo and Gangcheon water-quality monitoring stations in South Han River were selected to compare and analyze the variation of concentration before and after Ipo and Gangcheon Weirs construction, using the whole 4-year's data, from 2005 to 2008 and from 2014 to 2017. Water-quality constituents such as BOD and COD relating to oxygen demanding wastes and TP and Chlorophyll-a relating to the process of nutrient enrichment called eutrophication were also selected. The guidelines for water-quality control and management after weir construction including evaluation of water-quality constituents' variations can be presented by this paper.

• Journal of IKEEE
• /
• v.22 no.2
• /
• pp.266-273
• /
• 2018

Smart surveillance system obtains the positional information of users using GPS receivers embedded in smart devices, and provide them with services of tracking, monitoring, and protecting by controlling CCTVs nearby them. In order to apply and operate these systems to new environment, the overall setup process of the system is increased proportionally to the number of CCTVs. Therefore if there is a large number of CCTVs, the amount of time required during the setup process is very lengthy, and the operation of them becomes inoperable. In this paper, we propose a method to reduce these setting process. As the result of applying and simulation the proposed method, the setup method is simple, and as the CCTV increases, it consumes less time the previous system, and the system can be operated during setup.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.20 no.6
• /
• pp.77-83
• /
• 2020

The heat treatment facility is in a situation where the scope of application of the remote IOT system is expanding due to the harsh environment caused by high heat and long working hours among the root industries. In this heat treatment process environment, the IOT middleware is required to play a pivotal role in interpreting, managing and controlling data information of IoT devices (sensors, etc.). Until now, the system controlled by the heat treatment remotely was operated with the command of the operator's batch system without overall monitoring of the site situation. However, for the safety and precise control of the heat treatment facility, it is necessary to control various sensors and recognize the surrounding work environment. As a solution to this, the heat treatment safety support system presented in this paper proposes a support system that can detect the access of the work manpower to the heat treatment furnace through thermal image detection and operate safely when ordering work from a remote location. In addition, an OPEN CV-based deterioration analysis system using DNN deep learning network was constructed for faster and more accurate recognition than general fixed hot spot monitoring-based thermal image analysis. Through this, we would like to propose a system that can be used universally in the heat treatment environment and support the safety management specialized in the heat treatment industry.