Browsing Institutt for elektro, IT, og kybernetikk by Issue Date
Now showing items 41-60 of 281
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Modeling and optimization of coolant channel cross sections in induction heating coils
(Journal article; Peer reviewed, 2011)In induction heating applications where high currents and intermittent power application dominate, thermal fatigue can be a limiting factor of the service life of the induction coil. The outer geometry of the coil is often ... -
A Sensor Fusion Algorithm for Filtering Pyrometer Measurement Noise in the Czochralski Crystallization Process
(Journal article; Peer reviewed, 2011)The Czochralski (CZ) crystallization process is used to produce monocrystalline silicon for solar cell wafers and electronics. Tight temperature control of the molten silicon is most important for achieving high crystal ... -
Delayed density-dependent onset of spring reproduction in a fluctuating population of field voles
(Journal article; Peer reviewed, 2011)Delayed density-dependent demographic processes are thought to be the basis for multi-annual cyclic fluctuations in small rodent populations, but evidence for delayed density dependence of a particular demographic trait ... -
Modelling and control of a typical high head hydropower plant
(Conference object; Peer reviewed, 2011)This paper describes an effective mathematical model of a hydropower plant and how a decentralized control strategy for frequency and terminal voltage can be simulated. Several dynamic equations are presented for each ... -
High current arc erosion on copper electrodes in air
(Journal article; Peer reviewed, 2011)An arc fault inside metal enclosed switchgear will cause the pressure to rise and vaporization of electrode material may contribute to the pressure rise. An experimental study of high current arc erosion on copper electrodes ... -
Discrete LQ optimal control with integral action: A simple controller on incremental form for MIMO systems.
(Journal article; Peer reviewed, 2012)A simple Linear Quadratic (LQ) optimal controller of velocity (incremental) form with approximately the same properties as a conventional PID controller of velocity form is presented, i.e. integral action. The proposed ... -
Acoustic chemometric prediction of total solids in bioslurry: A full-scale feasibility study for on-line biogas process monitoring
(Journal article; Peer reviewed, 2012)Dry matter is an important process control parameter in the bioconversion application field. Acoustic chemometrics, as a Process Analytical Technology (PAT) modality for quantitative characterisation of dry matter in complex ... -
Acoustic chemometrics for material composition quantification in pneumatic conveying - The critical role of representative reference sampling
(Journal article; Peer reviewed, 2012)Reliable monitoring of pneumatically conveyed particulate materials is critical for online detection and controlling material composition changes in the regimen of Process Analytical Technology (PAT), e.g. as the case ... -
The Good Gain method for simple experimental tuning of PI controllers
(Journal article; Peer reviewed, 2012)A novel experimental method { here denoted the Good Gain method { for tuning PI controllers is proposed. The method can be regarded as an alternative to the famous Ziegler-Nichols' Ultimate Gain method. The approach taken ... -
Optimization of lift gas allocation in a gas lifted oil field as non-linear optimization problem.
(Journal article; Peer reviewed, 2012)Proper allocation and distribution of lift gas is necessary for maximizing total oil production from a field with gas lifted oil wells. When the supply of the lift gas is limited, the total available gas should be optimally ... -
Multimodal Tomometry for Slug Detection in two Phase Flow
(Journal article; Peer reviewed, 2012)Electrical Capacitance and Resistance Tomometric (ECTm/ ERTm) approaches are attractive for measurement and control applications in the process industries. By using the time series of raw resistance and capacitance values ... -
Co-operative sensor fusion using time warping in multimodal tomometry for process con
(Conference object; Peer reviewed, 2012)Recent studies in process tomography have mostly focused on image processing and enhancement of images obtained from Electrical Capacitance, Electrical Resistance, Electrical Impedance, Gamma- and X-ray- tomographic ... -
Steady-state analysis and voltage control of self-excited induction generator (SEIG)
(Chapter; Peer reviewed, 2012)Self-Excited Induction Generators have become the prime choice for wind energy conversion in remote and rural areas due to many advantages over Grid Connected Induction Generators. However, their main drawback is poor ... -
Online estimation of wax deposition thickness in single-phase sub-sea pipelines based on acoustic chemometrics: A feasibility study
(Journal article; Peer reviewed, 2012-10-25)Wax deposition in sub-sea oil producing pipelines is a concern to the oil producing companies. The deposition of wax in pipelines can cause serious economic implications if not monitored and controlled. Several researchers ... -
Adapting dynamic mathematical models to a pilot anaerobic digestion reactor
(Journal article; Peer reviewed, 2013)A dynamic model has been adapted to a pilot anaerobic reactor fed diarymanure. Both steady-state data from online sensors and laboratory analysis anddynamic operational data from online sensors are used in the model ... -
Optimal control strategies with nonlinear optimization for an Electric Submersible Pump lifted oil field
(Journal article; Peer reviewed, 2013)In an Electric Submersible Pump (ESP) lifted oil field, the ESP of each oil well should be operated inside its operating window. The total power consumed by the ESPs in the oil field should be minimized. The speed of the ... -
Relaxed Ziegler-Nichols closed loop tuning of PI controllers
(Journal article; Peer reviewed, 2013)A modification of the PI setting of the Ziegler-Nichols closed loop tuningmethod is proposed. The modification is based on a combination of the Skogestad SIMCtuning formulas for ´´integrator plus time-delay´´ processes ... -
Model Predictive Control with Integral Action: A simple MPC algorithm
(Journal article; Peer reviewed, 2013)A simple Model Predictive Control (MPC) algorithm of velocity (incremental) form is presented. The proposed MPC controller is insensitive to slowly varying system and measurement trends and therefore has integral action. ... -
Temperature control of a pilot anaerobic digestion reactor
(Journal article; Peer reviewed, 2013)Results of analysis and design and implementation of a temperature control system for a practical pilot anaerobic digestion (AD) bioreactor fed with dairy waste are presented. A dynamic model of the reactor temperature is ... -
On-Off and PI control of methane gas production of a pilot anaerobic digestion reactor
(Journal article; Peer reviewed, 2013)A proposed feedback control system for methane flow control of a real pilot anaerobic digestion reactor fed with dairy waste is designed and analyzed using the modified Hill model, which has previously been adapted to the ...