• Title/Summary/Keyword: water control

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Research on Environmentally-Sound Erosion Control Works(I) -Environment-oriented erosion control works in Japan- (환경(環境)과 조화한 사방사업(砂防事業)(I) - 일본의 환경보전사방(環境保全砂防) -)

  • Chun, Kun-Woo;Ezaki, Tsugio
    • Journal of Forest and Environmental Science
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    • v.12 no.1
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    • pp.13-25
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    • 1996
  • In recent erosion control works, securing not only the disaster prevention space but the environmental space, harmonized with surrounding environment and abundant with biological resources, are emphasized. Inspired of by the fact that efforts to secure such spaces have been being briskly promoted in Japan since the beginning of 1990s', we compile and analyze the Japanese sources about the "environmentally-sound erosion control works" to contribute to the erosion control works of our country. Specifically, in this report, we deal with the subjects of "establishment of the comfortable river environment" and "environmentally-sound erosion control works" which includes "erosion control dam", "water channel works and revetments", "fish routes" and "water quality conservation works".

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Design and control of extractive distillation for the separation of methyl acetate-methanol-water

  • Wang, Honghai;Ji, Pengyu;Cao, Huibin;Su, Weiyi;Li, Chunli
    • Korean Journal of Chemical Engineering
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    • v.35 no.12
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    • pp.2336-2347
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    • 2018
  • The azeotrope of methyl acetate methanol and water was isolated using extractive distillation with water as entrainer. The pressure-swing extractive distillation (PSED) process and vapor side-stream distillation column (VSDC) with the rectifier process were designed to separate the methyl acetate, methanol and water mixture. It was revealed that the VSDC with the rectifier process had a reduction in energy consumption than the PSED process. Four control schemes of the two process were investigated: Double temperature control scheme (CS1), $Q_R/F$ feedforward control of reboiler duty scheme for PESD (CS2), $Q_R/F$ feedback control scheme for VSDC (CS3), the feedback control scheme of sensitive plate temperature of side-drawing distillation column to dominate the compressor shaft speed (CS4). Feed flow and composition disturbance were used to evaluate the dynamic performance. As a result, CS4 is a preferable choice for separation of methyl acetate-methanol-water mixture. A control scheme combining the operating parameters of dynamic equipment with the control indicators of static equipment was proposed in this paper. It means using the sensitive plate temperature of side-drawing column to control the compressor shaft speed. This is a new control scheme for extractive distillation.

A Study on the Administration for the Han River Water Quality Control (漢江 水質保全 行政에 관한 硏究)

  • Kim, Kwang Hyop
    • Journal of Environmental Health Sciences
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    • v.10 no.2
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    • pp.9-40
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    • 1984
  • This thesis purports to overview the diverse administrative and organizational factors and plannings developed by the government organizations, municipal or otherwise, to tackle the Han River water pollution issues in the past years. This thesis also looks into the ever-worsening Han River water pollution problems, in particular, in terms of the various government plans ostensibly designed to reduce the pollution level but with little success. Also dealt with are the efficiencies with which the laws and decrees on water pollution the administrative organizations put to use in the prosecution of the diverse antiwater pollution projects involving the Han River basin. From the early 1960's up to the 1970's the government had concentrated on the growth-oriented economic policy with the result that little attention had been paid to the water pollution and other environmental issues that are bound to arise from the massive economic growth. Belatedly, the five-year Hah River Development Project was initiated in 1982 with emphasis on reducing the water pollution level at Hah River to the minimum. The following are the gists of the thesis and recommendations for the future antiwater pollution plans by the administrative organizations: 1. Documents to date indicate that the irrigation projects along the Han River area had been the main focus of attention during the Yi Dynasty and under the Japanese rule of the country. 2. Despite that the water pollution issue became the subject of many debates among the academic and research institutions in the 1960's and in the 1970's, the administrative organizations in charge of the Han River water quality control failed to come up with a concrete plan for the river's water quality control. 3. Nevertheless, the water pollution of the Han River area in fact began in the 1950's, with the unprecedented concentration into Seoul of population and the industrial facilities on a larger scale, in particular, enforced by the government's strong growthoriented policy in its Economic Development plans in the 1960's. 4. Starting in the 1960's, the Han River water pollution level dramatically increased, but the government was reluctant to promulgate or put into effect strong measures to curb the many factors contributing to the river water pollution, thus worsening the environmental issues along the Han River basin. 5. The environmental protection law and other laws and decrees relating to the antiwater and air pollution issues that were subsequently put into effect underwent so many changes that efficient anti-water pollution policies could not be effected for the Han River basin. The frequent organizational reshuffle within the administrative units concerned with environmental problems has resulted in the undue waste in personnel management and finance. 6. The administration on the environmental protection could not be efficiently carried out due to the organizational overlapping. Under the existing law, frequent organizational frictions and inefficiency are bound to occur among the central government offices themselves, as well as between the central government and the Seoul city administration, and among the city's administrative offices over the conservation of the Han River basin and over the river's anti-water pollution issue. 7. In the planning and prosecution of the Han River project, political influences from the president down to the lower-level politicious appear to have been involved. These political influences in the past had certainly had negative influence on the project, nevertheless, it appears that in the recent years, these political influences are not all that negative in view of the fact that they serve as a positive contributing factor in developing a better water quality control project along the Han River basin. The following are a few recommendations based on the data from the thesis: First, officials in charge of the Han River water quality control should pay attention to a careful screening of the opinions and recommendations from the academic circles and from the public should be made so that the government could better grasp the core issues in the environmental problems that require preventive and other necessary measures. Second, vigorous redistribution policies of population and industrial facilities away from the Seoul area should be pursued. Third, the government should refrain from revising or revamping too frequently the laws and decrees on the anti-water pollution, which is feared to cause undue inconveniences in the environmental administration. Fourth, a large-scale streamlining should be made to the existing administrative organization in an effort to do away with the inter- and intra-organizational friction. It is recommended that a secretariat for the Hah River basis conservation be established. Fifth, High-level administrative officials, with a thorough knowledge and vision on the Han River water quality control, should be prepared to better deal with the budgeting and personnel management for the Han River water pollution control not only at the control government, but also at the Seoul city municipal government levels. Environmental issues should be kept distinct from political issues. Environmental issues should not serve as a window-dressing for sheer political purposes. Sixth, the Hah River proiect should also include, along with the main Han River basin, those areas covering North Han River, South Han River, and the tributaries to the main river basin. The 'Han River Basin Water Quality Control Board' should be established immediately as a means of strengthening the current Han River basin water quality control policy. Seventh, in drawing up the Han River proiect, the administrative officials should be aware that Han River basin is a life line for those people in the region, providing them with not only a sheer physical space, but with a psychological living space for their everyday life.

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Automation Development in Water and Wastewater Systems

  • Olsson, Gustaf
    • Environmental Engineering Research
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    • v.12 no.5
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    • pp.197-200
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    • 2007
  • Advanced control is getting increasingly demanded in water and wastewater treatment systems. Various case studies have shown significant savings in operating costs, including energy costs, and remarkably short payback times. It has been demonstrated that instrumentation, control and automation (ICA) may increase the capacity of biological nutrient removing wastewater treatment plants by 10-30% today. With further understanding and exploitation of the mechanisms involved in biological nutrient removal the improvements due to ICA may reach another 20-50% of the total system investments within the next 10-20 years. Disturbances are the reason for control of any system. In a wastewater treatment system they are mostly related to the load variations, but many disturbances are created also within the plant. In water supply systems some of the major disturbances are related the customer demand as well as to leakages or bursts in the pipelines or the distribution networks. Hardly any system operates in steady state but is more or less in a transient state all the time. Water and energy are closely related. The role of energy in water and wastewater operations is discussed. With increasing energy costs and the threatening climate changes this issue will grow in importance.

WAETER LEVEL CONTROL USING Z-80 MICROOMPUTER

  • Sugisaka, Masanori
    • 제어로봇시스템학회:학술대회논문집
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    • 1991.10b
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    • pp.1899-1903
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    • 1991
  • This paper presents a water level control method using Z-80 microcomputer. The process considered in this paper is one tank system which is described by an unknown nonlinear differential equation. The water level is measured by the end of bar installed at a float passing through 8 pair of photointerrupters located at equal distance. Therefore, the input data to 8255 which is interface between Z-80 and photointerrupters is discrete value, namely, value under 1. values from 1 to 8, and value upper 8. The water is pumped into the tank from a reservoir by switching on a relay connected to a moter and pump driving system. The pumping is stopped by switching off the relay. Experimental studies for two types of controllers are performed in order to investigate the control performance of water level of the water pumping system.

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Controller design to diminish oscillation and steady state error in water temperature systems with drive delay

  • Nakamura, Masatoshi
    • 제어로봇시스템학회:학술대회논문집
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    • 1991.10b
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    • pp.1888-1893
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    • 1991
  • Systematic design of a controller for a water temperature system was considered, with the intention of devising an accurate control experiment. The results of an experiment using a water temperature system based on the pole placement regulator showed water temperature oscillation and steady state error. This paper proposed a. method for eliminating both the oscillation and the steady state error. The oscillation was eliminated by a drive delay compensation technique, in which a future state value of the system was predicted through a real time computer simulation. The steady state error was eliminated by an steady state error correction technique, in which an actual steady state heatrate in the system model was replaced by an imaginary heatrate. By combining these two techniques, we obtained an experimental result for water temperature control of 0.01 (.deg. C) accuracy. Furthermore, the proposed method was evaluated relatively by comparing the experimental results using several other methods and proved to be the most accurate and convenient control method for the delay system.

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Optimum chemicals dosing control for water treatment (상수처리 수질제어를 위한 약품주입 자동연산)

  • 하대원;고택범;황희수;우광방
    • 제어로봇시스템학회:학술대회논문집
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    • 1993.10a
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    • pp.772-777
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    • 1993
  • This paper presents a neuro-fuzzy modelling method that determines chemicals dosing model based on historical operation data for effective water quality control in water treatment system and calculates automatically the amount of optimum chemicals dosing against the changes of raw water qualities and flow rate. The structure identification in the modelling by means of neuro-fuzzy reasing is performed by Genetic Algorithm(GA) and Complex Method in which the numbers of hidden layer and its hidden nodes, learning rate and connection pattern between input layer and output layer are identified. The learning network is implemented utilizing Back Propagation(BP) algorithm. The effectiveness of the proposed modelling scheme and the feasibility of the acquired neuro-fuzzy network is evaluated through computer simulation for chemicals dosing control in water treatment system.

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Design and Control of a Firefight Cannon Manipulator Applying Sliding Mode Control

  • Vu, Mai The;Choi, Hyeung-Sik;Kang, Hyeon-Seung;Bae, Jae-Hyeon;Joo, Moon-G.;Joo, Yeong-do
    • Journal of Advanced Marine Engineering and Technology
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    • v.39 no.5
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    • pp.554-562
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    • 2015
  • This paper describes an analysis of an architecture and control system of a firefighting cannon manipulator (FCM) composed of two joint axes and one water-shooting actuator. Because the orienting FCM motion is disturbed by the reaction force from water shooting, the water shooting force has been modeled for robust control. The dynamics model of the manipulator has been set up including the external force of water-shooting reaction on the manipulator. A PD Controller and Sliding Mode Controller have been designed and their performance been tested through simulation to track a desired trajectory under the disturbance of a water-shooting reaction. The simulation shows that the performance of the Sliding Mode Controller is better than that of the PD controller.

Internet Based Remote Control and Monitoring for the System to purify water (인터넷 기반 오폐수 처리 시스템의 원격제어 및 모니터링)

  • Seo, Won-Yong;Yeon, Jun-Sang;Yang, Oh
    • Proceedings of the KIEE Conference
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    • 2002.11c
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    • pp.457-460
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    • 2002
  • This paper is study on internet based remote control and monitoring for the system to purify water. environment of the water quality grew worse. therefore we require the effective system to purify water now national internet based remote control and monitoring make a sensation and are a problem to be solved. This paper demonstrate internet based remote control and monitoring for the system to purify water. This system including on server and many client distributed in whole country. The server is collecting information from the client. this information is then written inside Database. The Database is dealing with Website and Server and Client.

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Wireless Remote Control and Monitoring for the System to purify water (오폐수처리시스템의 무선원격제어 및 모니터링)

  • Lee, Hyuck-Jin;Seo, Yong-Won;Yang, Oh
    • Proceedings of the KIEE Conference
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    • 2003.07d
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    • pp.2115-2117
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    • 2003
  • This paper is study on internet based wireless remote control and monitoring for the system to purify water. Environment of the water quality grew worse. Therefore we require the effective system to purify water. Now national internet based wireless remote control and monitoring make a sensation and are a problem to be solved. This paper demonstrate internet based wireless remote control and monitoring for the system to purify water. This system including on server and many client distributed in whole country. The server is collecting information from the client. This information is then written inside database. The database is dealing with website and server and client.

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