Kauko Leiviskä

University of Oulu · Control Engineering Laboratory

Predictive information on plant diseases could help to reduce and optimize the usage of pesticides in agriculture. This research presents classification procedures with linear discriminant analysis to predict three possible severity levels of net blotch in spring barley in Finland. The weather data utilized for classification included mathematical...

The set of traditional characteristic features of large-scale complex systems (LSS) included the large number of variables, structure of interconnected subsystems, and other features that complicate the control models, such as nonlinearities, time delays, and uncertainties. The advances in information and communication technologies (ICT) and the mo...

The performance of meteorological data-based methods to forecast plant diseases strongly depends on temporal weather information. In this paper, a data analysis procedure is presented for finding the optimal starting time for forecasting net blotch density in spring barley based on meteorological data. For this purpose, changes in the information c...

The optimal operation of fuel cells in changing environmental and variable load conditions requires mathematical modeling. The electrochemical behavior of polymer electrolyte membrane fuel cells (PEMFC) is commonly described with a semi‐empirical model requiring fuel cell specific model parameter values. A large number of different nature inspired,...

The advanced steel grades and high productivity requirements in the modern steel industry subject production machines to increased mechanical stresses, which inflicts losses. Novel data-oriented solutions to the monitoring of machines have a pivotal role in loss prevention, but the industrial data with high sampling rates, noise, and dimensions bri...

A novel data analysis method for the evaluation of plant disease risk that utilizes weather information is presented in this paper. This research considers two different datasets: open weather data from the Finnish Meteorological Institute and long-term (1991–2017) plant disease severity observations in different hardiness zones in Finland. Histori...

The effect of moisture content and feasibility of its estimation in granular material was investigated via machine vision. The test scheme consisted of saw dust samples derived from Norway spruce with moisture content adjusted to three distinct levels. The effect of moisture when present as ice or liquid water was compared. The experimental procedu...

This study is focused on the application of automated techniques on low-speed bearing diagnostics. The diagnosis in low-speed conditions is hampered by the long periods between defect-related impulses and the high level of noise relative to the magnitude of the impulses. To detect a localised defect in such conditions, a new approach that uses vibr...

Easily adaptable indoor temperature and heat demand models were applied in the predictive optimization of the heat demand at the city level to improve energy efficiency in heating. Real measured district heating data from 201 large buildings, including apartment buildings, schools and commercial, public, and office buildings, was utilized. Indoor t...

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...

Nitriding is a heat treatment process that is commonly used to enhance the surface properties of ferrous components. Traditional quality control uses sacrificial pieces that are destructively evaluated. However, efficient production requires quality control where the case depths produced are non-destructively evaluated. In this study, four differen...

In this paper, a more holistic approach to nuclear qualification processes is proposed to better understand the concept of qualified automation for nuclear power plants. A life cycle-based conceptual framework for the nuclear qualification of automation is presented in order to facilitate re-use of qualified engineering artefacts. The proposed conc...

Implementation of new energy efficiency measures for the heating and building sectors is of utmost importance. Demand side management offers means to involve individual buildings in the optimization of the heat demand at city level to improve energy efficiency. In this work, two models were applied to forecast the heat demand from individual buildi...

The Theory of Inventive Problem Solving (TRIZ) can be applied to generate new concepts for process intensification (PI). In order to meet the target performance of the intensified process and to avoid design bottlenecks due to process operation, the suggested concepts need to comprise a feasible control system. Therefore, a design step, where a sys...

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

An advanced model-based control method for the integrated fuel processing and a fuel cell system consisting of ethanol reforming, hydrogen purification, and a proton exchange membrane fuel cell is presented. For process identification, a physical model of the process chain was constructed. Subsequently, the simulated process was approximated with d...

The applications of evolutionary optimizers such as genetic algorithms, differential evolution, and various swarm optimizers to the parameter estimation of the fuel cell polarization curve models have increased. This study takes a novel approach on utilizing evolutionary optimization in fuel cell modeling. Model structure identification is performe...

Predictive models are potential tools for assessing changes in a water treatment process and water quality, and to be used as assistance in process control to ensure the production and distribution of high quality drinking water to consumers with lower operation costs. In this work, mathematical variable selection methods were utilized to find the...

The application of process intensification (PI) techniques in solids handling processes requires careful assessment of challenges and limitations set by the solid phase present in the process streams. Preferably, the PI implementation involves a holistic way of thinking that covers all necessary aspects during the design phase. One of the key requi...

A novel dynamic model for the temperature inside buildings is presented, aiming to improve energy efficiency by providing predictive information on the heat demand. To analyse the performance and generalizability of the modelling approach, real measurement data was gathered from five different types of buildings. Easily available data from various...

Evolutionary optimizers, such as genetic algorithms, have earlier been successfully applied to find the parameter values for the fuel cell polarization curve models. The structure of these, typically semi-empirical, models have evolved during the decades. In this study, the model structures were reviewed and a new model structure was generated. Gen...

The production of gear components includes numerous manufacturing operations, which are carried out to ensure proper surface characteristics. Shot peening is one of the surface finishing processes used for transmission components like gears to improve their fatigue behavior. Shot peening increases the compressive residual stresses on the surface, a...

The production of gear components includes numerous manufacturing operations which are carried out to ensure proper surface characteristics of components to deal with wear and fatigue. Surface shot peening is one way to increase the compressive residual stresses on the surface and thus ensure better wear and fatigue resistance. An experimental plan...

Methanol synthesis has drawn a lot of attention and its product, methanol, is assumed to be one of the key issues of future global energy discussion. The sustainable and cost-effective process can be achieved by successful process design, control, and optimization. In this context, an accurate process model is the important tool for process develop...

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...

A static model for a basic oxygen furnace process in SSAB steel plant is described in this paper. The model aims for predicting the so called distribution factor describing how the chemical elements fed into the process are distributed into the outlet streams. A multi-model approach is used where sub-models use regression models with interaction an...

Traditionally the modelling in an activated sludge process has been based on solely the process measurements but as the interest to optically monitor wastewater samples to characterize the floc morphology has increased, in the recent years the results of the image analyses have been more frequently utilized to predict the characteristics of wastewa...

Wastewater samples taken from the aeration tank of a full-scale activated sludge plant were analyzed using an automatic optical monitoring device. Five variable selection methods were utilized to find the optimal subsets of input variables to develop predictive models for the important parameters of the wastewater treatment process efficiency and t...

The Finnish Lapland is the most sparsely populated region in Europe and the population is decreasing all the time. The constantly growing tourist visits and overnight stays cause large amounts of wastes and erosion of local nature. Tightening waste regulations and increasing fossil energy prices provide motivation to improve local waste processing...

The energy industry is striving for cost-efficient production with low emissions. The efficiency of energy conversion processes is one of the most important factors affecting the path to such a goal. This paper provides a framework for the monitoring of steam boiler operation in power stations. The framework is based on the use of historical proces...

A truly two-dimensional view of the paper web during production could be realized in a cost-efficient manner with the present web inspection systems (WIS). This study evaluates the capability of image-based measurements, such as the light transmittance images captured with WIS, in paper machine profile control. Simulated bump tests are conducted on...

Monitoring of mineral beneficiation processes is difficult due to lack of reliable measurements and hazardous environment. Therefore robust models describing steady-state and dynamic behaviour of the processes are needed when aiming for improved monitoring and control. Specific characteristics of models used in mineral processes are that they requi...

A novel optical monitoring device was used for imaging an activated sludge process in-situ during a period of over one year. In this study, the dependencies between the results of image analysis and the process measurements were studied, and the optical monitoring results were utilised to predict the important quality parameters of the wastewater t...

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...

Even though industry consumes nearly half of total energy production, the relative share of total energy consumption related to heating and operating buildings is growing constantly. The motivation for this study was to reveal the differences in electricity use and district heating consumption in school buildings of various ages during the working...

The evolution of electricity grids into a smart grid requires the inclusion of control systems to control load, flatten peaks and ensure the distribution of electricity. In parallel, the building sector will also be incorporating more control technology and put emphasis on sustainability issues such as reducing CO2 emissions associated with the bui...

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...

Frequency spectrum, bispectrum and bicoherence which are computed from Barkhausen noise (BN) signal are used to model material properties. The use of frequency domain information can be a significant addition to the more common time domain data analysis of the BN signals. The frequency spectrum shows the magnitude of the spectral components present...

This paper presents the results of using a systematic approach for identifying the interactions between splashing and the variables measured from the basic oxygen furnace. Splashing is a phenomenon in BOF, where a small portion of material (both slag and steel) is splashing from the BOF in an uncontrolled manner. This causes unwanted material losse...

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...

Smart grids are meant to reach multiple goals such as leveling the electricity demand profile, reducing electricity consumption and increasing the energy efficiency of the electrical grid. Smart buildings play an important role in achieving these goals. With an increased number of measuring and controlling tools, new problems also arise, such as th...

This paper presents an approach to real time condition monitoring of an epicyclic gearbox in a hydroelectric power plant. Early and reliable change and fault detection in an epicyclic gearbox is important, because a failure may cause long out-of-service time. The hydroelectric power plant is used to provide load following power to the electrical gr...

Smart grids are meant to reach multiple goals such as leveling the electricity demand profile, reducing electricity consumption and increasing the energy efficiency of the electrical grid. Smart buildings play an important role in achieving these goals. With an increased number of measuring and controlling tools, new problems also arise, such as th...

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...

This paper discusses the life-cycle environmental impact of Home Energy Management System (HEMS), in terms of their potential benefits and detrimental impacts. It is the expectation that adapting smart home automation (SHA) would lead to reduced electricity usage in the household and overall environmental advantages. The purpose of this research wa...

The traditional batch wet granulation processes encounter several challenges, such as problems in the scale-up step, batch-to-batch variability together with the multivariate and difficult to control nature of the process. A continuous wet granulation technique could be a possible solution for the scale-up problem, offering adjustable production vo...

Combining first-principles knowledge in the form of a mechanistic model with artificial neural networks (ANN) into so-called hybrid models is an attractive approach to improve models for biological wastewater treatment. Although neural networks have been proven to be an effective method in learning nonlinear input-output mappings, their generalizat...

To achieve the decarbonisation of the energy sector in Europe, the CO2 emission profile of energy consumption must be fully understood. A new methodology for accounting for CO2 emissions is required for representing the dynamics of emissions. In this article, a dynamic integration of CO2 emissions due to the electricity production and trade was dev...

This paper presents early results of the development steps taken in order to build a static model of a basic oxygen furnace for SSAB Raahe steel plant. The model aims for being used as a part of a plant-wide control system. Model development includes pre-processing and actual modelling steps. The modelling step uses a pre-selected set of input vari...

This paper describes a static flow sheet simulation model developed for the pilot scale mineral beneficiation plant taken recently into use at University of Oulu, Finland. The mini-pilot plant aims to serve as a research platform for students and researchers from universities, mining companies, and other organizations in the field of mining and min...

In this study, Barkhausen noise (BN) magnetizing voltage sweep (MVS) measurement is used to evaluate non-destructively the surface residual stress state of hardened components. A new computational feature, where the maximum slope of the sweep is divided by the corresponding magnetizing voltage, is introduced. The results show that this feature has...

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...

The objective of this work was to develop a log loading simulator of the wood room in pulp and paper industry. In the first stage the log loading process is modelled. Then the criteria for evaluating the effects of log loading on the wood room performance are defined. The motivation for the research is that log loading can be identified as playing...

The purpose of this paper is to analyse the log loading process of wood room, which is typically the first processing unit in pulp and paper mills. The aim is to improve the log loading process to obtain production with a constant log flow of well de-iced logs to the debarking drum. This way it is possible to reduce costs and enhance product qualit...

An interesting topic of recent Barkhausen noise (BN) method studies is the application of the method to case depth evaluation of hardened components. The utilization of BN method for this purpose is based on the difference in the magnetic properties between the hardened case and the soft core. Thus, the detection of case depth with BN can be achie...

This paper describes different approaches for utilizing frequency-domain information of Barkhausen noise (BN) signal in quantitative prediction of material properties. Different approaches include the calculation of power spectral density (PSD), moving window PSD for obtaining the BN profile and the utilization of the BN spectrum. The PSD value is...

Residual stress of case-hardened steel samples is predicted in this paper with the linear multivariable regression model. The development of the prediction model is based on the huge set of features calculated from the Barkhausen noise measurement signal among which the most suitable ones are chosen. The selection uses a genetic algorithm with leav...

Residual stresses are quantitatively predicted based on the Barkhausen noise measurement with a partial least squares regression model. The measurements are taken from two sets of case-hardened samples. The benefits of using certain feature elimination strategies prior model identification are also studied. The elimination methods applied are corre...

A nonlinear empirical model between stress and Barkhausen noise is identified in this study. The identification procedure uses a genetic algorithm followed by a Nelder-Mead optimization procedure. The model is identified with the data set where an external load is applied to RAEX400 low alloyed hot-rolled steel samples. The results of the study sho...

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...

This paper presents a model of a detached house in which home automation has been progressively introduced into the building. The model integrates different factors related to end-user behaviour and decision-making regarding the management of electrical energy consumption, and integrates a gradual end-user response to home automation measures. The...

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 estimation of the quality properties of the paper web is mainly based on sparse scanning measurements. This measurement system has some wellknown disadvantages, but the solutions for alternative measurement principles have been found expensive. The recent development in imaging technology and data processing enables web imaging with a current w...

Full text available at: http://www.scs.illinois.edu/suslick/documents/matsciforum.1996.pdf Optical emission spectrometry, OES, has been used widely to define the chemical element analysis. The possibility to use OES-PDA-data to identify the amount of inclusions in steel has been studied to get a quick knowledge about inclusions during the process....

Full text available at: http://www.ipcbee.com/vol51/016-ICEEB2013-A10018.pdf The quality of indoor air is commonly measured by temperature, humidity and carbon dioxide (CO2) sensors. Volatile Organic Compounds (VOCs) are usually analyzed using air samples, but also sensors that detect odors and gases are available. In this study, Total Volatile Org...

Full text available at: http://www.ipcbee.com/vol51/004-ICEEB2013-A013.pdf Schools are suitable type of buildings for Indoor Air Quality (IAQ) measurements. This is justified by the fact that IAQ measurements can ensure a comfortable and healthy environment for educational purposes. The aim of this study is to assess IAQ measurement correlations in...

Full text available at: http://www.drink-water-eng-sci.net/6/39/2013/dwes-6-39-2013.pdf In water treatment processes, aluminum salts are widely used as coagulation chemical. High dose of aluminum has been proved to be at least a minor health risk and some evidence points out that aluminum could increase the risk of Alzheimer's disease. Thus it is i...

Nopeasti kehittyvä kaivosautomaatio asettaa monipuolisia vaatimuksia tietoliikenne- ja - järjestelmäratkaisuille. Tiedonsiirtokanavia pitkin on kyettävä välittämään niin mittaukset, prosessin säädöt, ääni kuin kuvakin. Tietojärjestelmillä on kyettävä hoitamaan mm. tuotannon suunnittelu, valvonta ja ohjaus sekä erilaisten kulutus-, käyttö- ja ympäri...

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...

Barkhausen kohina -mittaus on potentiaalinen ainetta rikkomaton testausmenetelmä, joka soveltuu ferromagneettisille materiaaleille. Menetelmän käytettävyyttä rajoittaa se, että saatavat tulokset ovat lähinnä kvalitatiivisia. Tässä paperissa kuvataan lyhyesti tutkimuksia, joissa on keskitytty materiaaliominaisuuksien kvantitatiiviseen ennustamiseen...

Full text available at: http://www.aidic.it/cet/13/32/347.pdf Continuous processes could be applied to improve cost-efficiency of pharmaceutical manufacturing that has traditionally relied on batch processing due to regulatory requirements and small lot sizes. However, in order to utilize this new approach and to meet the end-product requirements,...

Context: Continuous processing is becoming popular in the pharmaceutical industry for its cost and quality advantages. Objective: This study evaluated the mechanical properties, uniformity of dosage units and drug release from the tablets prepared by continuous direct compression process. Materials and methods: The tablet formulations consiste...

Calibration samples for the Barkhausen noise (BN) method were produced with laser processing. A planet gear wheel used for production quality control was subjected to laser irradiation to verify the BN sensor output. Different samples were found to respond similarly to the laser processing although the laser parameters needed to be adjusted for dif...

Full text available at: http://link.springer.com/chapter/10.1007%2F978-3-642-34156-4_24#page-1 Networked control systems (NCS) could be utilised in several industrial applications. However, the variable time delays introduced by the network impair the NCS performance, resulting even in the instability of the controlled process. To mitigate the dela...

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...