Esko Juuso

University of Oulu · Control Engineering Group, Faculty of Technology

Evolutionary computing is widely used to tune intelligent systems which incorporate expert knowledge with data. The linguistic equation (LE) approach is an efficient technique for developing truly adaptive, yet understandable, systems for highly complex applications. Process insight is maintained, while data-driven tuning relates the measurements t...

Purpose – The purpose of this paper is to develop a comprehensive approach to efficiently integrate maintenance and operation by combining process and condition monitoring data with performance measures. Design/methodology/approach – Intelligent stress, condition and health indicators have been developed for control and condition monitoring by com...

A combined signal processing and feature extraction approach can be based on generalised moments and norms, which are defined by the order of derivation (α), the order of the moment (p) and sample time (τ), where α and p are real numbers. The analysis can be further improved by taking into account nonlinear effects by monotonously increasing scalin...

Advanced signal processing methods combined with automatic fault detection enable reliable condition monitoring for long periods of continuous operation. Rapid changes in acceleration become emphasised upon derivation of the signal x(2). Higher order derivatives, especially x(4), work very well in the whole range from slowly to very fast rotating r...

Temporal reasoning is a very valuable tool to diagnose and control slow processes. Identified trends are also used in data compression and fault diagnosis. Although humans are very good at visually detecting such patterns, for control system software it is a difficult problem including trend extraction and similarity analysis. In this paper, an int...

This paper proposes an assessment of features orientated to improve the accuracy of a hybrid model (HyM) used for detecting faults in a heating, ventilation, and air conditioning (HVAC) system. The HyM combines data collected by sensors embedded in the system with data generated by a physics-based model of the HVAC. The physics-based model includes...

Stress monitoring systems are not always included in machinery, and this might create a need for a retrofitted system. Programmable Logic Controller (PLC) units, mini PCs and other similar hardware are nowadays widely available at a reasonable price, which makes this type of hardware an interesting choice for retrofitted monitoring systems. However...

Fault diagnosis can utilise signal processing in various ways: informative time domain signals are separated or transformed from the source signals and used in feature extraction to find useful fault indicators. Frequency domain analyses focus on identifying interesting signal components. This research integrates different solutions together: diffe...

Fatigue mechanisms proceeding through the formation and growing of cracks are well-known but the progress is not easy to detect with measurements during the operation. The localised structural damage is caused by repeated loading and unloading when the load exceeded certain thresholds. The effect of the loading is highly nonlinear and structures fr...

The aim of wastewater treatment plants (WWTPs) is to clean wastewater before it is discharged into the environment. Real-time monitoring and control will become more essential as the regulations for effluent discharges are likely to become stricter in the future. Model-based soft sensors provide a promising solution for estimating important process...

The principles and methodology of control science and engineering are relevant beyond engineered systems to all dynamical systems. In this paper we discuss how control terminology and concepts can be interpreted in the context of decision-making by human managers, and the benefits that can accrue from the analogy. Examples of managerial decision ma...

The coronavirus COVID-19 is affecting around the world with strong differences between countries and regions. Extensive datasets are available for visual inspection and downloading. The material has limitations for phenomenological modelling but data-based methodologies can be used. This research focuses on intelligent modelling on the basis of the...

For large-scale systems, the number of possible variable combinations becomes very large. Variable grouping means finding feasible groups of variables for modelling. Systems can be divided into subsystems but even then the number of available variables is often impractically high to be used with the data-based methods. Interactive variable selection...

The coronavirus COVID-19 is affecting around the world with strong differences between countries and regions. Extensive datasets are available for visual inspection and downloading. The material has limitations for phenomenological modeling but data-based methodologies can be used. This research focuses on the intelligent temporal analysis of datas...

Spectral analysis is a very common tool in vibration monitoring. While useful in machine diagnostics, spectral analysis can be rather time consuming. Tasks that require an extensive amount of time are often considered too expensive, especially in modern industry. To achieve an automatic monitoring system of some kind, different features, such as th...

Integration of domain expertise and uncertainty processing is increasingly important in automation solutions which rely on data analytics and artificial intelligence. We need a level to assess what is approximately correct. Uncertainties of the inputs are taken into account by using fuzzy numbers as the inputs of different fuzzy and parametric syst...

The continuous development of steel products generates new challenges for the maintenance of manufacturing machines in steel mills. Substantial mechanical stress is inflicted on the machines during the processing of modern high-strength steels. This increases the risks of damage and flaws in the processed material may appear if the capability of a...

Open Access Proceedings of the above mentioned conferences. http://www.ep.liu.se/ecp/contents.asp?issue=142

Increasing volumes of data, referred as big data, require massive scale and complex computing. Artificial intelligence, deep learning, internet of things and cloud computing are proposed for heterogeneous datasets in hierarchical analytics to manage with the volume, variety, velocity and value of the big data. These solutions are not sufficient in...

Engineering education needs to provide both theoretical knowledge and problem-solving skills. Many topics can be presented in lectures and computer exercises are good tools in teaching the skills. Learning by doing is combined with lectures to provide additional material and perspectives. The teaching scheme includes lectures, computer exercises, c...

Solar thermal power plants collect available solar energy in a usable form at a temperature range which is adapted to the irradiation levels and seasonal variations. Solar energy can be collected only when the irradiation is high enough to produce the required temperatures. During the operation, a trade-off of the temperature and the flow is needed...

New monitoring methods are required to enhance the operation of a wastewater treatment process and to meet the constantly tightening regulations for the effluent discharges. An on-line optical monitoring device, that analyses the morphological parameters of the flocs, have been showed to a potential tool for assessing the wastewater quality and the...

Performance improvement is taken as the primary goal in the asset management. Advanced data analysis is needed to efficiently integrate condition monitoring data into the operation and maintenance. Intelligent stress and condition indices have been developed for control and condition monitoring by combining generalized norms with efficient nonlinea...

Automatic fault detection with condition and stress indices enables reliable condition monitoring to be combined with process control. Useful information on different faults can be obtained by selecting suitable features. Generalised norms can be defined by the order of derivation, the order of the moment and sample time. These norms have the same...

Monitoring of water quality should not be solely based on laboratory samples. Such activity, although producing reliable results, cannot provide an accurate enough temporal coverage for water quality monitoring. The Finnish Environment Institute, SYKE, has therefore established numerous online water monitoring stations that continuously monitor wat...

A consistent representation is needed to understand meanings of the measurement values and use them together with knowledge-based information. The nonlinear scaling approach is used for any numeric values, including measurements, features, indices and indicators. The scaled values in the range [-2, 2] are interpreted in natural language labels, e.g...

A multiscale modeling procedure is introduced in this paper for modeling continuous high-shear wet granulation. Flow inside the granulator is accounted using the discrete element method (DEM) and particle-level interactions with population balance (PB). The developed DEM-PB model is validated against experiments, particle size distribution (PSD), a...

In condition monitoring, detecting changes in measured signals is often desired. Another crucial piece of information is the frequency, which shows the change. In industrial applications today, it is quite common to monitor some features, for example RMS value, and visually analyse the frequency spectrum for information about the frequency content....

Monitoring and control of water treatment plants play an essential role in ensuring high quality drinking water and avoiding health-related problems or economic losses. The most common quality variables, which can be used also for assessing the efficiency of the water treatment process, are turbidity and residual levels of coagulation and disinfect...

Maintenance of mining machinery is done by schedule or in the event of break down and this is area where it is possible to cut down in maintenance costs by lowering down time and preventing sudden break downs. Advanced on site signal processing enables early fault detection and improves maintenance planning by optimizing service intervals. This pap...

The early detection of fluctuations in operating conditions and fault detection is done with similar methods. The feature extraction uses statistical analysis based on generalised norms and moments. Intelligent stress indices are calculated from these features by nonlinear scaling. The scaling approach uses the norms and moments to produce indices,...

Water spray system is one of the most important parts of rock cutting machines, especially the drum shearer. Field data shows that the maintenance of this system is time-consuming and causes major downtimes in the coal mines’ production process. Therefore, it is essential to find an optimum preventive maintenance task and intervals, to reduce the d...

In condition monitoring detecting changes in measured signals is often desired. Another crucial piece of information is the frequency which shows the change. In industrial applications today, it is quite common to monitor some feature e.g. RMS value, and for information about the frequency content the frequency spectrum is visually analysed. The RM...

One activated sludge process line was optically monitored in-situ by a novel image analysis equipment. The results of the image analysis were studied to find out dependencies to the process variables of the wastewater treatment plant (WWTP) and to the quality of treated wastewater. The quality parameter of treated wastewater, suspended solids, was...

We discuss quality control of environmental measurement data. Typically, environmental data is used to compute some specific indicators based on models, historical data, and the most recent measurement data. For such a computation to produce reliable results, the data must be of sufficient quality. The reality is, however, that environmental measur...

Aktiivilietelaitoksen jäteveden ominaisuuksia monitoroitiin uudenlaisella kuva-analyysilaitteistolla ja kuva-analyysituloksia verrattiin jätevedenkäsittelyprosessin mittauksiin visuaalisesti sekä korrelaatioanalyysia käyttäen. Jätevedenpuhdistusprosessin toimivuutta kuvaava biologisesti käsitellyn jäteveden kiintoainepitoisuus mallinnettiin kuva-an...

Solar power plants should collect any available thermal energy in a usable form at the desired temperature range. Efficient operation requires a fast start-up and reliable operation in varying cloudy conditions without unnecessary shutdowns and start-ups. Fast and well damped linguistic equation (LE) controllers have been tested in Spain at a colle...

Machine diagnostics is usually based on measurements and monitoring changes in signals obtained. It is crucial to reliably determine if there have been changes in signals, as this is usually considered a sign of deteriorating condition of the machine. When correctly applied, generalised norms can provide a very good estimate about the changes in si...

Automatic fault detection with stress and condition indices enables reliable condition monitoring to be combined with process control. Useful information on different faults can be obtained by selecting suitable features from generalised norms, which are defined by the order of derivation, the order of the norm and sample time. The methodology sele...

One of the common quality parameters for drinking water is residual aluminium. High doses of residual aluminium in drinking water or water used in the food industry have been proved to be at least a minor health risk or even to increase the risk of more serious health effects, and cause economic losses to the water treatment plant. In this study, t...

Solar power plants collect available thermal energy in a usable form at the desired temperature range. Efficient operation requires a fast start-up and reliable operation in varying cloudy conditions without unnecessary shutdowns and start-ups. Fast and well damped linguistic equation (LE) controllers have been tested in Spain at a collector field,...

Solar power plants collect available thermal energy in a usable form at the desired temperature range. Efficient operation requires a fast start-up and reliable operation in varying cloudy conditions without unnecessary shutdowns and start-ups. Fast and well damped linguistic equation (LE) controllers have been tested in Spain at a collector field,...

Reliability, safety and efficiency of power plants become increasingly important due to the demand for cost-efficient energy production and tightening environmental regulations. Equipment malfunctions and faults are typical in industry but may lead to reduced production, shutdown of the plant or fatalities at the worst. Certain types of equipment f...

Maintenance operations have significant influence on the economy and performance of mining companies. Unpredicted repairs cause interruptions and breakdowns in production. This means economic losses but, in some cases, also increasing environmental emissions in off-gases and wastewater. Condition based maintenance (CBM) can significantly reduce mai...

Industrial wastewater treatment plants (WWTP), especially in pulp and paper mills, have operational problems resulting fluctuations in effluent discharges. The composition and flow rates of industrial wastewater fluctuate depending on the production schedules of the upstream processes. A lot of process measurements are available, but measurement se...

Drinking water quality is an important issue around the world since the low quality water causes health-related problems and economic losses. To ensure high quality water an efficient monitoring and control of a water treatment process is essential. In this study, two common quality variables of treated water, turbidity and residual aluminium, are...

The present invention relates to a method for automatic dose control of chemicals in liquid treatment, particularly for automatic dose control of chemicals in water treatment. The present invention also relates to a device arrangement for automatic dose control of chemicals. The invention utilizes adaptive linguistic equation controllers for dosing...

Automatic fault detection with condition indices enables reliable condition monitoring to be combined with process control. Useful information on different faults can be obtained by selecting suitable features from generalised norms, which are defined by the order of derivation, the order of the norm and sample time. The nonlinear scaling based on...

Epicyclic gearing or planetary gearing is a gear system that consists of one or more outer gears, or planet gears, revolving around a central, or sun gear. Typically, the planet gears are mounted on a movable arm or carrier, which itself may rotate relative to the sun gear. The complex structure consisting of many rolling elements and versatile com...

Fatigue is caused by repeated loading and unloading. The mechanism proceeds through cracks formed when the load exceeded certain thresholds. Structures fracture suddenly when a crack reaches a critical size. Intelligent stress indices based on nonlinear scaling provide good indicators of the severity of the load. The stress index Is is -2 when the...

This paper presents a tool, which is used in the identification of models for the estimation of the uncertainty of measurements in an on-line process monitoring application. The tool has three separate parts. The first part is used to identify simple linear regression models and limits for the measurements. The second part is used in the generation...

Several methods are applied to find the input variables with predictive power to the degree of desulphurization modelling. The methods are applied on the data from a desulphurization plant processing flue gases coming from a coal-fired power plant. In non-linear and complex industrial processes, the nature of the relationships between the variab...

Epicyclic gearing or planetary gearing is a gear system that consists of one or more outer gears, or planet gears, revolving around a central, or sun gear. Typically, the planet gears are mounted on a movable arm or carrier, which itself may rotate relative to the sun gear. It is challenging to monitor epicyclic gearboxes, due to their complex stru...

Fatigue is caused by repeated loading and unloading. The mechanism proceeds through cracks formed when the load exceeded certain thresholds. Structures fracture suddenly when a crack reaches a critical size. Intelligent stress indices based on nonlinear scaling provide good indicators of the severity of the load. The stress index Is is -2 when the...

Rapid changes in acceleration become emphasised upon the derivation of the acceleration signal x(2). Higher order derivatives work very well in the whole range from slowly to very fast rotating rolling bearings. Real order derivatives x(α) provide additional possibilities, and generalised norms with the real order p are used in feature extraction....

A process control system deals with disperse information sources mostly related with operation and maintenance issues. For integration purposes, a data collection and distribution system based on the concept of cloud computing is proposed to collect data or information pertaining to the assets of a process plant from various sources or functional a...

In this study, an approach to the detection of sensor faults is presented. It is based on an identification principle, which takes into account linear relationships between process variables and a key variable. Simple linear regression models are created for variables with a strong correlation. Relative limits are defined for the variables using ac...

Solar power plants should collect the available thermal energy in a usable form within a desired temperature range. The collection is controlled by the flow of oil pumped through the pipes during the plant operation. The control system consists of a nonlinear linguistic equation (LE) controller with predefined adaptation models, some smart features...

Temporal reasoning is a very valuable tool in the diagnosis and control of slow processes. In this study, an intelligent trend index is developed from the measurements of a wastewater treatment plant using short time periods to provide patterns for intelligent control. The data and trend analysis uses the previously developed approach: (1) the nonl...

In the presented work, a hybrid micro-grid simulator has been developed from the end-user point of view. The hybrid model includes a number of selectable elements for the production and storage of energy, making a (smart) use of the available renewable energy resources based on a demand-response principle. The main role of the simulator is to model...

Advanced data analysis is needed to efficiently integrate maintenance and operation. A good basis for this increasingly important task is process and condition monitoring data. Intelligent stress, condition and health indicators have been developed for control and condition monitoring by combining generalised moments and norms with efficient nonlin...

Early detection of faults and changes in the operation of an industrial plant brings financial benefits and facilitates the observance of environmental regulations. In this study, statistical approaches to generation of control limits for process measurements are discussed. Points falling outside of the limits are monitored to detect an abnormal...

Solar power plants should be designed to collect all the available thermal energy in a usable form within a desired temperature range. In cloudy conditions, the collector field is maintained in a standby mode ready for full-scale operation when the intensity of the sunlight rises again. Control is achieved by means of varying the flow of oil pumped...

Machines seldom break down suddenly without warning. Therefore, it is crucial to monitor the vibration levels as a function of time. Regression analysis and fuzzy reasoning with triangular episodic representations, which are based on the estimated first and second derivatives of a feature, have been used in trend analysis. Trend indices are calcula...

Trend monitoring of vibration level is a more useful maintenance tool than a one-time survey of the absolute magnitudes of features only. A slight linear increase of feature values turns to exponential when the point of failure is approaching. The time of failure depends strongly on machines and the stress caused by operating conditions. Signal pro...

Advanced signal processing methods combined with automatic fault detection enable reliable condition monitoring for long periods of continuous operation. Any attempt to detect different types of machine faults reliably at an early stage requires the development of improved signal processing methods. Vibration measurements provide a good basis for c...

Cavitation is harmful to water turbines and may cause shutdowns for several weeks. The real-time detection of cavitation risk is increasingly important, and even narrow cavitation-free power ranges can be utilised in load optimisation. Higher derivative signals calculated from acceleration signals and their lp norms detect the normal operating cond...

Early detection of fluctuations in operating conditions and fault detection can be done with similar methods. Signal processing is needed for the condition monitoring measurements, and interpolation is some process measurements and especially laboratory analysis. Effective time delays are very important in process data. Feature extraction uses stat...

The aim of dynamic modelling and simulation is to im-prove the control of the fluidised bed granulator. Mod-elling and simulation was done on the basis of data collected from several test campaigns. Several model-ling methodologies have been compared in Matlab-Simulink environment. A solution based on dynamic linguistic equation models was chosen....

Automatic fault detection with condition indices enables reliable condition monitoring to be combined with process control. Useful information on different faults can be obtained by selecting suitable features. Generalised norms can be defined by the order of derivation, the order of the moment and sample time. These norms have the same dimensions...

Advanced signal processing methods combined with automatic fault detection enable reliable condition monitoring for long periods of continuous operation. Rapid changes in acceleration become emphasised upon the derivation of the signal x(2). The aim is to detect faults at an early stage by using the absolute values of the dynamic part of the signal...

A multisensor approach has been used for fault diagnosis in a test rig that consists of an electric motor and a transmission between two axes with SKF single row ball bearings 6002. Two sensors measured axial vibration and five accelerometers radial vibration in the vertical direction. The rig was to simulate nine independent fault modes: rotor unb...

Engineering education needs to provide both theoretical knowledge and problem-solving skills. Many topics can be presented in lectures, and computer exercises are good tools in teaching the skills. Learning by doing is combined with lectures to provide additional material and perspectives. The teaching scheme combines lectures, computer exercises,...

Solar power plants should be designed to collect all the available thermal energy in a usable form within a desired temperature range. In cloudy conditions, the collector field is maintained in a standby mode ready for full-scale operation when the intensity of the sunlight rises again. Control is achieved by means of varying the flow of oil pumped...

The signals x(3) and x(4) are very suitable for the condition monitoring, and real order derivatives x(α) provide additional possibilities. Generalised moments τMαp and their lp norms are defined by the order of derivation (α), the order of the moment (p) and sample time (τ), which all are real numbers. The lp norms have the same dimensions as the...

Cavitation is harmful to water turbines and may cause shutdowns for several weeks. The real-time detection of cavitation risk is increasingly important, and even narrow cavitation-free power ranges can be utilised in load optimisation. Higher derivative signals x(α), α = 3 or 4, calculated from acceleration signals x(2) are very suitable for detect...

Increasing globalization of the economy is imposing tough challenges to manufacturing companies. The ability to produce highly customized products, in order to satisfy market niches, requires the introduction of new features in automation systems. Flexible manufacturing processes must be able to handle unforeseen events, but their complexity makes...

The importance of nutritional guidance grows as nutritional problems, such as obesity and type-2 diabetes, are becoming more common. Nutritional guidance is carried out by mapping the nutritional state of an individual using a food diary and by comparing the nutrition intake levels to the recommended reference values. Typically, the expert knowledg...