• Journal of Korean Society on Water Environment
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• v.32 no.6
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• pp.528-536
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• 2016

The purpose of Total Pollution Load Control at Tributary is to obtain maximum improvement effect of water quality through finding the most impaired section of water-body and establishing the proper control measure of pollutant load. This study was implemented to determine the optimal management of reach, period, condition, watershed, and pollution source and propose appropriate reduction practices using the Load duration curve (LDC) and field monitoring data. With the data of measurement, LDC analysis shows that the most impaired condition is reach V (G4~G5), E group (flow exceedance percentile 90~100%) and winter season. For this reason, winter season and low flow condition should be preferentially considered to restore water quality. The result of pollution analysis for the priority reach and period shows that agricultural nonpoint source loads from onion and garlic culture are most polluting. Therefore, it is concluded that agricultural reuse of surface effluent (storm-water runoff with non-point sources) and low impact farming that includes reducing fertilization and controlling the height of drainage outlet are efficient water quality management for this study watershed.

• Journal of Korean Society for Atmospheric Environment
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• v.33 no.6
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• pp.533-543
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• 2017

As the public interest in environmental issues increased, the "Act On The Integrated Control Of Pollutant-Discharging Facility" was enacted. Through the integrated environmental pollution prevention act in which 19 industries with large environmental impacts are sequentially applied, pollutants can be managed in a medium-integrated manner and integrated permission of the business unit is possible and BAT can be applied to enable a scientific and proactive environmental management system. In order to facilitate the implementation of integrated environmental pollution prevention act with these advantages, the BAT BREF should be published, modified and revised every 5 years considering the level of scientific development. This study reviewed the issues to be considered in applying BAT and the types of BAT and focused on presenting improvements and development direction when revising and supplementing the standards in the future based on these contents. For this purpose, when revising the standards, it will be necessary to reflect on the domestic situation, to expand the TWG(Technical Working Group) of small-scale workplace experts, and to exchange opinions with business places that have similar processes for each waste type through a systematic total inspection. In addition to these methods, by establishing a resident participation system through information disclosure, it is expected to be used as a guideline for environmental management of business places not subject to integrated permission of less than 3 types as well as those subject to integrated permission.

• Environmental engineer
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• s.184
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• pp.74-79
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• 2001

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.124-127
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• 1997

In this paper, we propose a method of cooperative control based on immune system in distributed autonomous robotic system(DARS). Immune system is living body's self-protection and self-maintenance system. Thus these features can be applied to decision making of optimal swarm behavior in dynamically changing environment. For the purpose of applying immune system to DARS, a robot is regarded as a B lymphocyte(B cell), each environmental condition as an antigen, and a behavior strategy as an antibody respectively. The executing process of proposed method is as follows. When the environmental condition changes, a robot selects an appropriate behavior strategy. And its behavior strategy is simulated and suppressed by other robot using communication. Finally much simulated strategy is adopted as a swarm behavior strategy. This control scheme is based on clonal selection and idiotopic network hypothesis. And it is used for decision making of optimal swarm strategy.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.5 no.3
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• pp.503-516
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• 2001

At present, environmental control system of greenhouses related with industrial automation in the korea is composed of on/off-type control machine using a timer in facilities requiring intensive labor. This system, however, makes it difficult for us to find out any status of environmental control system in greenhouses when we are situated in a remote area or at midnight. In this paper we improved a system to monitor status for manual and automatic control by means of PC by replacing an existing on/off-type controller with a display panel, It also attempts to implement DB for information on corps and to provide a user with the efficiency of getting information for plants.

• Journal of Korean Society on Water Environment
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• v.34 no.3
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• pp.339-345
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• 2018

The integrated environmental permit system is currently in operation online. It carries out various functions of postmanagement such as the submission of annual reports containing operations management data onto integrated management workplaces, the operation and management of emission facilities and prevention facilities, and the disclosure of information on the integrated permission. On the other hand, the integrated environmental permit system needs to perform various roles in order to stably manage and smoothly perform the permitting work. It is necessary to utilize this system to establish policies by using diverse operations management data onto integrated management workplaces collected in the integrated environmental permit system. This system can also play a role in improving the post-management system and user convenience after the permission review and approval processes. The integrated environmental permit system can be effectively used to set up the BAT-AEL because it collects all of the cross-media data and identifies the overall status of the workplace. In order to establish a post management system after the approval, it is necessary to provide performance management and performance evaluation functions as conditions of the permit after approval. In addition, a variety of support functions should be provided to enable the permission authority and the environmental expert examination agency to facilitate the review of permits. It will be necessary to provide an evaluation system and a proactive diagnostic function to determine whether permission conditions and permit emission standards will change in the future. Also, it is important to adopt an information exchange platform that can be used to collect the status data onto the workplaces; the platform can also be used as an information exchange site for technical working groups (TWG), and for collecting field experts' opinions.

• Smart Structures and Systems
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• v.13 no.2
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• pp.305-318
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• 2014

This paper numerically investigates the feasibility of an active mass damper (AMD) system using the time delay control (TDC) algorithm, which is one of the robust and adaptive control algorithms, for effectively suppressing the excessive vibration of a building structure under wind loading. Because of its several attractive features such as the simplicity and the excellent robustness to unknown system dynamics and disturbance, the TDC algorithm has the potential to be an effective control system for mitigating the vibration of civil engineering structures such as buildings and bridges. However, it has not been used for structural response reduction yet. In this study, therefore, the active control method combining an AMD system with the TDC algorithm is first proposed in order to reduce the wind-induced vibration of a building structure and its effectiveness is numerically examined. To this end, its stability analysis is first performed; and then, a series of numerical simulations are conducted. It is demonstrated that the proposed active structural control system can effectively reduce the acceleration response of the building structure.

• Structural Engineering and Mechanics
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• v.17 no.3_4
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• pp.557-572
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• 2004

Control systems are used to limit structural lateral deflections during large external loads such as winds and earthquakes. Most recently, the semi-active control approach has grown in popularity due to inexpensive control devices that consume little power. As a result, recently designed control systems have employed many semi-active control devices for the control of a structure. In the future, it is envisioned that structural control systems will be large-scale systems defined by high actuation and sensor densities. Decentralized control approaches have been used to control large-scale systems that are too complex for a traditional centralized approach, such as linear quadratic regulation (LQR). This paper describes the derivation of energy market-based control (EMBC), a decentralized approach that models the structural control system as a competitive marketplace. The interaction of free-market buyers and sellers result in an optimal allocation of limited control system resources such as control energy. The Kajima-Shizuoka Building and a 20-story benchmark structure are selected as illustrative examples to be used for comparison of the EMBC and centralized LQR approaches.

• Earthquakes and Structures
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• v.11 no.6
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• pp.1077-1099
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• 2016

One of the main shortcomings in the current passive base isolation system is lack of adaptability. The recent research and development of a novel adaptive seismic isolator based on magnetorheological elastomer (MRE) material has created an opportunity to add adaptability to base isolation systems for civil structures. The new MRE based base isolator is able to significantly alter its shear modulus or lateral stiffness with the applied magnetic field or electric current, which makes it a competitive candidate to develop an adaptive base isolation system. This paper aims at exploring suitable control algorithms for such adaptive base isolation system by developing a close-loop semi-active control system for a building structure equipped with MRE base isolators. The MRE base isolator is simulated by a numerical model derived from experimental characterization based on the Bouc-Wen Model, which is able to describe the force-displacement response of the device accurately. The parameters of Bouc-Wen Model such as the stiffness and the damping coefficients are described as functions of the applied current. The state-space model is built by analyzing the dynamic property of the structure embedded with MRE base isolators. A Lyapunov-based controller is designed to adaptively vary the current applied to MRE base isolator to suppress the quake-induced vibrations. The proposed control method is applied to a widely used benchmark base-isolated structure by numerical simulation. The performance of the adaptive base isolation system was evaluated through comparison with optimal passive base isolation system and a passive base isolation system with optimized base shear. It is concluded that the adaptive base isolation system with proposed Lyapunov-based semi-active control surpasses the performance of other two passive systems in protecting the civil structures under seismic events.

• Journal of Korean Society on Water Environment
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• v.39 no.4
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• pp.343-355
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• 2023

After the implementation of the total pollution load control system, the effect of improving river water quality by expanding investments in basic environmental facilities, inducing operational efficiency, and reducing the load of various pollutants was clear. However, since the implementation of the system, the management of non-point pollutants has been neglected; management focused on specific substances (biochemical oxygen demand (BOD) and total phosphorus (T-P)) and lacked specific cause analysis and action plans, failed to establish a relationship between water quality and pollution load, failed to reflect stakeholder demands for river water quality management, and failed to apply technical conditions. Therefore, to overcome the limitations raised and achieve a practical and efficient advanced total pollution system, the current system was partially improved and will continue to be improved. This study analyzed the performance and limitations of the total pollution system and introduced recent improvements and the contents that are being improved. The main contents included reducing emissions and reduction monitoring, using water quality tele-monitoring system (TMS) data and self-measurement data, adding population-inducing facilities, and adjusting regional development projects from 20 to 30 multi-family housing units, currentizing each pollutant source according to the roadmap. If the system is improved in a developmental direction and responds to various changes, it will be a more practical and effective policy.