Nitrogen Removal in a Real-Time Controlled Sequencing Batch Membrane Bioreactor

The performance of a real-time controlled Sequencing Batch Membrane Bioreactor (SBMBR) for removing organic matter and nitrogen from synthetic wastewater has been investigated in this study under two specific ammonia loadings of 0.0086 and 0.0045g NH4+-N gVSS−1 day−1. Laboratory results indicate that both COD and DOC removal are greater than 97.5% (w/w) but the major benefit of using membrane for solid-liquid separation is that the effluent can be decanted through the membrane while aeration is continued during the draw stage. With a continued aeration, the sludge cake layer is prevented from forming thus alleviating the membrane clogging problem in addition to significant nitrification activities observed in the draw stage. With adequate aeration in the oxic stage, the nitrogen removal efficiency exceeding 99% can be achieved with the SBMBR system. Furthermore, the SBMBR system has also been used to study the occurrence of ammonia valley and nitrate knee that can be used for real-time control of the biological process. Under appropriate ammonia loading rates, applicable ammonia valley and nitrate knee are detected. The real-time control of the SBMBR can be performed based on on-line ORP and pH measurements.

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Modifications of rainfall runoff and decision finding models for on-line simulation in real time control

Water Science & Technology ◽

10.2166/wst.1999.0477 ◽

1999 ◽

Vol 39 (9) ◽

pp. 201-207

Author(s):

Andreas Cassar ◽

Hans-Reinhard Verworn

Keyword(s):

Real Time ◽

Urban Drainage ◽

Rain Event ◽

Rainfall Runoff ◽

Real Time Control ◽

Design Storm ◽

Time Control ◽

Timing Data ◽

On Line ◽

Rainfall Runoff Model

Most of the existing rainfall runoff models for urban drainage systems have been designed for off-line calculations. With a design storm or a historical rain event and the model system the rainfall runoff processes are simulated, the faster the better. Since very recently, hydrodynamic models have been considered to be much too slow for real time applications. However, with the computing power of today - and even more so of tomorrow - very complex and detailed models may be run on-line and in real time. While the algorithms basically remain the same as for off-line simulations, problems concerning timing, data management and inter process communication have to be identified and solved. This paper describes the upgrading of the existing hydrodynamic rainfall runoff model HYSTEM/EXTRAN and the decision finding model INTL for real time performance, their implementation on a network of UNIX stations and the experiences from running them within an urban drainage real time control project. The main focus is not on what the models do but how they are put into action and made to run smoothly embedded in all the processes necessary in operational real time control.

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Toward a Real Time Control of Toolpath in Milling Processes

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.554-557.706 ◽

2013 ◽

Vol 554-557 ◽

pp. 706-713 ◽

Cited By ~ 1

Author(s):

Fabien Poulhaon ◽

Matthieu Rauch ◽

Adrien Leygue ◽

Jean Yves Hascoet ◽

Francisco Chinesta

Keyword(s):

Real Time ◽

Constant Thickness ◽

Efficient Production ◽

Cnc Machine ◽

Real Time Control ◽

Time Control ◽

Online Measurements ◽

Bilateral Approach ◽

On Line ◽

Cnc Controller

Real-time control of manufacturing processes is a challenging issue for nowadays industry. The need for ever more efficient production requires new strategies in order to make correct decisions in an acceptable time. In a large number of cases, operators working on a CNC machine tool have a reduced number of possibilities for interacting in real-time with the machine. Numerical simulation based control is in that sense an appealing alternative to the conventional approach since it provides the operator with an additional source of information, confirming his choices or in reverse suggesting a more adapted strategy. The main goal of this work is to propose a method to move from a bilateral approach (operator and CNC controller) to a trilateral one where the simulation is an active component of the manufacturing process. This paper focuses on a simple issue sometimes encountered in milling processes: how to remove a constant thickness of material at the surface of a part whose exact geometry is unknown? The difficulty lies in the choice of an appropriate trajectory for the tool. So far the method which is employed consists in acquiring the geometry of the part thanks to a palpation step made prior to milling. However, this step has to be repeated for each part and can become rather fastidious as the size of the part increases. The approach presented here gets rid of the palpation step and makes use of online measurements for identifying the real geometry and correcting the trajectory of the tool in accordance. By monitoring the forces applying on the tool (directly on the NC), we have access to the milling depth and therefore to the geometry of the part at several locations along the trajectory of the tool. This information is used as an input data for our numerical model running on an external device, which finally derives an approximation for the geometry. An optimized trajectory is then obtained and is updated on the machine. This procedure is repeated as the tool moves forward and it allows for a fast and robust on-line correction of the toolpath.

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Development and Implementation of a Real-Time Control System for Nitrogen Removal Using OUR and ORP as End Points

Industrial & Engineering Chemistry Research ◽

10.1021/ie0488851 ◽

2005 ◽

Vol 44 (9) ◽

pp. 3367-3373 ◽

Cited By ~ 41

Author(s):

Sebastià Puig ◽

Lluís Corominas ◽

M. Teresa Vives ◽

M. Dolors Balaguer ◽

Jesús Colprim ◽

...

Keyword(s):

Control System ◽

Real Time ◽

Nitrogen Removal ◽

Real Time Control ◽

End Points ◽

Time Control

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Prediction in real-time control using adaptive networks with on-line learning

Proceedings of IEEE International Conference on Control and Applications CCA-94 ◽

10.1109/cca.1994.381366 ◽

1994 ◽

Cited By ~ 3

Author(s):

Brockmann ◽

Huwe

Keyword(s):

Real Time ◽

Adaptive Networks ◽

Real Time Control ◽

Time Control ◽

On Line ◽

On Line Learning

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Real-Time Control of the Heating of an Airfoil

Volume 1: Advanced Computational Mechanics; Advanced Simulation-Based Engineering Sciences; Virtual and Augmented Reality; Applied Solid Mechanics and Material Processing; Dynamical Systems and Control ◽

10.1115/esda2012-82460 ◽

2012 ◽

Author(s):

Francoise Rétat-Masson ◽

Francisco Chinesta ◽

Adrien Leygue ◽

Elias Cueto ◽

Laurent Dala ◽

...

Keyword(s):

Real Time ◽

Additional Data ◽

Proper Generalized Decomposition ◽

Real Time Control ◽

Simulation Tools ◽

Time Control ◽

Application Systems ◽

Simulation Based ◽

On Line ◽

Measurement Devices

Dynamic Data-Driven Application Systems constitute nowadays one of the most challenging applications of simulation-based Engineering Science [1]. DDDAS imply a set of techniques that allow the linkage of simulation tools with measurement devices for real-time control of systems and processes [2]. DDDAS entails the ability to dynamically incorporate additional data into an executing application, and in reverse, the ability of an application to dynamically steer the measurement process. These systems need accurate and fast simulation tools, hence the off-line computations to limit as much as possible the on-line computations. In order to obtain the most efficient solver, all the sources of variability are introduced as extra-coordinates as to solve only once the model off-line to obtain its most general solution to be then considered in on-line purpose. However, such models result defined in highly multidimensional spaces. A technique recently proposed, called Proper Generalized Decomposition [3], allows circumventing this redoubtable curse of dimensionality.

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An application of real-time control systems to robotics

Robotica ◽

10.1017/s0263574700003167 ◽

2001 ◽

Vol 19 (3) ◽

pp. 323-329 ◽

Cited By ~ 3

Author(s):

Carmen Monroy ◽

Ricardo Campa ◽

Rafael Kelly

Keyword(s):

Control Systems ◽

Real Time ◽

Control Algorithm ◽

Computing Environment ◽

Real Time Control ◽

Time Control ◽

On Line ◽

Robot Performance ◽

Single Processor ◽

Selection Of

This paper illustrates basic concepts of real-time control systems through the application of a real-time single-processor computing environment for the control of a robotic arm. The paper describes elements for the selection of the real-time architecture, the control algorithm and the graphical user interface. The system provides an opportunity for users to verify the robot performance by changing on-line the controller parameters and the shape of the desired motion.

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