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Paper presents three optically supplied protection systems developed for use for a fiber segment in a Passive Optical Network and gives assessment and comparison of their characteristics with respect to application of an optical supply.

In this work the conception of the fiber Bragg grating (FBG) application in the capacity of the temperature distribution sensor, on the grating length, is presented. In the method of temperature distribution measurement, by using of FBG element, the key issue is an estimation of the grating periods distribution (and connected with this estimation - temperature distribution) from measured grating transmission spectrum (an inverse problem). The article presents measurements results used for evaluation of selected methods for solving an inverse problem, which can be used in temperature distribution recovery from FBG spectrum. We have also presented utility evaluation results of the selected methods for numerical solution of the inverse problem for temperature distribution recovery.© (2008) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

In the paper, the modified correlation method is presented as well as results of CO concentration measurements in laboratory conditions using this method. Measurements were obtained for high CO concentrations (exceeding 50%) and short optical path (1 and 2m long). The measurements can be treated as a reference for measurements for far low concentrations and longer optical paths. Some simulation results also has been presented showing influence of temperature and pressure on measurement accuracy.

The article describes methodology and results of research on remote optical power supply at low illumination levels. Such approach is a result of studies on passive optical networks extended with optically powered active components made beforehand.

The results of the fiber Bragg grating reconstruction problem were introduced in this work. This process was conducted by using of Genetic algorithm. The proposals of the ways of modeling structures of fiber Bragg gratings by the use of the object-oriented programming and by the use of the direct and inverse problem were introduced in this article.

This paper describes an application of curvelet transform analysis problem of interferometric images. Comparing to two-dimensional wavelet transform, curvelet transform has higher time-frequency resolution. This article includes numerical experiments, which were executed on random interferometric image. In the result of nonlinear approximations, curvelet transform obtains matrix with smaller number of coefficients than is guaranteed by wavelet transform. Additionally, denoising simulations show that curvelet could be a very good tool to remove noise from images.

In this article the proposals of the ways of modelling structures of fiber Bragg gratings by the use of the object-oriented programming and by the use of the direct and inverse problem were introduced. The results of the inverse problem solution, done for Bragg gratings, were also introduced in this work. This process was conducted by using of local optimization algorithms.

At consideration of fiber optic waveguide devices in a lection course the primary attention is paid to analysis features and facilities of planar and cylindrical waveguides in systems of communication, information transmission and procession in real time and also to efficiency of applying semiconductor radiation sources in these systems.

There is no method of direct measurement of amount coal dust supplied to the burner, as well as a primary air. It is important in avoiding flame instabilities that could lead flame extinguishing and thus, improve both safety and combustion quality. One of the quickest way of drawing information of a combustion process is to analyze its radiation. The article presents investigation of flame image features, that could point to a state of unstable combustion. Several combustion tests of pulverized coal have been done, generating stable and unstable state of combustion. In this article, some flame image parameters as image energy, entropy and median have been investigated as combustion quality pointers.

A content measurement of chosen ingredients in a gas mixture can be done with optical methods, e.g. using optical fibres. Their undoubted advantages are lack of disturbance of a medium to be measured and possibility of application in aggressive media. In the article, experiments have been described, aimed at developing a cheap CO-analyser, that would be based on a modified correlation method. Such an analyser could be utilized in content measurement of carbon monoxide in near-wall layer of power boiler. It could be treated as a pointer of corrosion thread in a power boilers.

In this work is explored the effectiveness of application of various absorption laser spectroscopy methods for definition of gas components concentration in boilers' smoke gases. O2 and CO absorption spectrums are parsed, optimum absorption lines in near IR spectrum range (about 0.76 microns for O2 and 1.56 microns for CO) are selected and graphics of selected lines intensities and half-widths dependences on the temperature of controllable medium and pressure in it are given. Processes of monitoring of CO and O2 content in boilers smoke gases are simulated at usage of basic laser spectroscopy methods (integral, differential, modulation, correlation, modified correlation) and measurement inaccuracies are analyzed. It is ascertained, that for a decrease of methodical errors of concentration measuring it is necessary to take into account operated medium temperature and pressure. It is shown, that the least inaccuracies of CO and O2 concentration continuous monitoring at the presence of dissipative losses variations are ensured with the modified correlation method though its threshold sensitivity is less, than integral and correlation ones.

In this paper, we have presented a reliable simulation of algorithm for the recovery of the fiber Bragg grating (FBG) parameters from their reflection spectrum. An accurate method for synthesizing the physical parameters of the fiber Bragg grating has been proposed and demonstrated on the bans of its reflectivity. The method is based on gradient optimization algorithms and can be applied over each type of gratings (uniform, apodized, chirped, phase shifted). We have proposed a new technique, which has overcome some of existing disadvantages and restrictions by using information about the reflection characteristics from grating, which we have examined, and also using the transmission characteristics. As an example, the proposed technique may be successfully applied to synthesize and characterize our experimental grating which is uniformed, apodized and linearly chirped, from FBG measured reflectivity. This method could be applied for distribution strain and temperature sensing applications if only we have some previous information about the unstrained FBG and also if the possible strain profiles are known. Our algorithm for the synthesis of FBGs from reflectivity has no limitations in parameter space. We don't have to reduce the problem to small number of parameters. In most of practical cases, our technique would fast lead to accurate synthesis results. The proposed method can efficiently lead to optimal solutions and at the same time it takes into account various requirements of the examined grating. This study and simulations are supported by initial laboratory experiments, and this allow us to suppose, that there is a real possibility of complete, fast, and accurate characterization (including phase characterization) of FBG structures from reflectivity measurements.

This paper presents research on adaptive control (AC) of combustion process in industry. Results were obtained from research conducted in laboratory combustion chamber with usage of Fibre Optical Measurement System (FOMS) with electronic block. Simulation proved that implementing AC and FOMS to burning process improves flue gasses parameters - direct measure of power boiler ecological and economical quality of work.

Flame radiation intensity and its changes in time domain deliver the quickest and straight information of a combustion process. We have compared combustion of coal-biomass mixture and reference coal through flame image analysis. The aim of the research was finding flame's shape features, that could point to a state of unstable combustion, for the fuels being considered. Several combustion tests have been made in a laboratory stand for pulverized coal mixed with paper sludge (10%) with variable coal flow. The stand was equipped with scaled down (1:10) low-NO x burner. Flame images were recorded by a standard monochrome camera and captured by a frame grabber. After conversion to black-and-white images, changes of some shape parameters such as flame area, its horizontal and a vertical dimensions and shape coefficient have been investigated.

Semiconductor lasers, which can be surely characterize by many of their advantages, have been used for measurements of concentration of gases for many years. Doing measurements in industrial conditions, because of its several difficulties, needs using special technology of measurements. In this article using modified, correlated absorption spectroscopy, in order to measure CO concentration, has been shown.

The work will present results of laboratory investigation of optoelectronic detector of carbon monoxide that uses anexternal cavity semiconductor laser tuned within 1,5 and 1,6tm. Measurement set-up incorporates cells im and 2m longcontaining the measured gas at variable concentration. Such set-up reflects the product of partial pressure and pathlength that can be found inside the power boiler.Keywords: absorption spectroscopy, low-oxygen corrosion, measurements of carbon monoxide, combustion diagnostic 1. INTRODUCTION A concentration measurement of various gases is one of fields being rapidly developed in various branches of industry.It also applies to the power industry. Measurements of concentration of carbon monoxide, nitrogen oxides or sulfurdioxide in flue gases for the sake of environment protection monitoring can be an example. In order to limit an emissionof harmful substances to the atmosphere the technology of combustion is being changed. The so called low-emissiontechnologies characterized by air stepping are being applied what allows to reduce concentration of NOx in flue gases.It turns out yet, that correct and safe combustion process control needs not only analysis of the outlet gases but also ananalysis of environment inside the power boiler.Research conducted by various centers [1, 2, 3] proved that application of the low-emission combustion technologies isaccompanied by accelerated degradation of the elements of a power boiler —

There are several tens of burners operating in a power boiler and their control based on averaged and delayed measurements (e.g. gas analyzers located inside the chimney) is often not enough effective. The article describes attempts to obtain information about levels of emission of nitrogen oxides and carbon monoxide from the signals of the fiber-optic flame monitoring system developed in the Department of Electronics of the Technical University of Lublin. Artificial neural networks are used for estimation of emission. The article contains description of an object and the measurement system as well as results of research of nitrogen oxides and carbon monoxide modeling.

An analyse of evolutionary algorithm operation allows us to understand how controlled spontaneity of an individual specimen leads to dynamic order of the whole community that efficiently uses emerging adaptive possibilities. This paper presents sequel of research concerning implementation of GA in controlling burning process in industrial conditions. A simulation was conducted and proved that implementing GA to the process is possible and brings improvement of flue gases parameters, what is a direct measure of power boiler quality of work, both in ecologic and economical way.

In this paper a FBG (Fiber Bragg Grating) sensor for measuring temperature and temperature distribution is presented. We have used a phase retrieval algorithm for the temperature measurement. There is presented a method for obtaining the distributed temperature distribution along a fiber Bragg grating by measuring the reflectivity spectrum. We have also a priori knowledge about the complex coupling coefficient's magnitude.

The flame monitoring system is intended to use in industrial condition for controlling pulverized coal combustion in power boiler. Placing the fiber-optic probes close to the each burner, one can obtain detailed information of the coal combustion process within the single burner. In order to enhance flame-monitoring system sensitivity for detection of fuel's composition changes, we have measured flame emission spectra.

This paper presents review of optical radiation measurement method in combustion process. Analysis and comparison of different methods is described and some applications in coal combustion boilers are shown. Such sensors can detect presence of target molecule, measure concentration ratio of two molecules and quantitatively measure the concentration.

In this article initial works to the point of examination of Fiber Bragg Grating (FBG) sensors are presented. We describe this works in the context of use FBG elements in construction of temperature sensors. We have compared theoretical assumptions and studies with practical results, which had been received in first lab examinations.

Operation of combustion process in power boilers in such a way that pollution standards are met and corrosion is limited requires continuous measurement of concentration of selected gases in the near wall layer of power boilers. The absorption spectroscopy is one of methods that allow such measurement. Specificity of the medium in which the measurement is to be made (among other things: high temperature, difficulties in installation of sources and detectors) requires utilization of optical fiber technology. Absorption spectra overlapping in the medium infrared range is an additional hindrance which makes application of special measurement algorithms necessary. A concept of structure of optoelectronic analyzer of CO concentration in the near wall layer of power boilers has been presented. The analyzer is based on modified correlation absorption spectroscopy within the range between 1557 nm and 1600 nm. Simulation results have been presented as well.

A transition to multilevel system of preparation of specialists at Belarussian State University required educational process system reorganization. It supposed rebuilding all the curricula, but also was used for methodical improvements. The process is stil in progress and authors describe their experience in management of teaching of semiconductor quantum electronics in the transition period.© (2004) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

In this paper we present initial analysis of time series obtained from fiber optic monitoring system. The results indicate that application of GA (Genetic Algorithm) for control of nitrogen oxides (NOx) emission from power burner brings promising results and perspectives for development of fiber optic sensors for combustion quality evaluation.© (2004) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Burning pulverized coal in power boilers causes considerable emission of atmospheric pollution. In order to decrease it the combustion process itself has been modified, however at cost of side effects like: increased level of unburned coal particles in the ashes. There are tens of burners in a single power boiler and emission level measurements are made in flue gas duct, so the control based on such averaged and heavily delayed values often results ineffective. The neural controller of the pulverized coal burner attempts to resolve these problems. The clue is utilization of fiber-optic system for monitoring of chosen zone of flame developed in Department of Electronics of Technical University of Lublin. The article contains description of controlled system and optical fiber measurement system, an idea of the controller as well as some results obtained for experimental burner.

Methods of determination of coordinates of the center of a narrow radiation beam by means of the CCD array are considered. For the continuous representation of images and noises the analytical expressions describing signal and noise functions at the output of optimal spatial filter are obtained, as well as the dispersion of optimal estimation of a position of Gaussian radiation beam. It is shown that using the CCD array the minimum error of estimation of the Gaussian beam position is observed when the beam effective diameter is approximately equal to 0.8 of lateral length of a light-sensitive cell of the array.

A new way leading to estimate Fiber Bragg Gratings (FBG) parameters is presented. We describe calculating influence of accuracy of FBG execution on their basic characteristics. In this paper we report and present an FBG element as an optical fiber sensor. An FBG quality characterize two mainly essential parameters. There are Full Width at Half Maximum to stand for FWHM (also presented as Δλ ) and reflection index to stand for R . We examine influence of accuracy of FBG with reference to following quantity: modulation of the refraction index Δn and the grating period Λ . On the basis of well known analytical relationship which describe FWHM and R we have estimated influence of FBG construction on above parameters. After obtain final analytical dependences we make suitable graphs to depict all calculations.© (2004) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The fiber optic monitoring system was utilized in controlling combustion of pulverized coal with some additives. These additives have a negative influence on combustion stability, which eventually can lead to flameout. To be based on optical signals corresponding to flame radiation intensity contained within a region defined by NA of optical fibers, it is possible to foresee a flameout. It can be done by converting optical signal into electrical form and applying sophisticated methods of signal analysis such as wavelet transform.

Burning pulverized coal in power boilers causes considerable emission of atmospheric pollution. In order to decrease it the combustion process itself has been modified, however at cost of side effects like: increased level of unburned coal particles in the ashes. There are tens of burners in a single power boiler and emission level measurements are made in flue gas duct, so the control based on such averaged and heavily delayed values often results ineffective. The neural controller of the pulverized coal burner attempts to resolve these problems. The clue is utilization of fiber-optic system for monitoring of chosen zone of flame developed in Department of Electronics of Technical University of Lublin. The article contains description of controlled system and optical fiber measurement system, an idea of the controller as well as some results obtained for experimental burner.

This paper presents sequel of research concerning implementation of GA in controlling burning process in industrial conditions. Results obtained from research conducted in laboratory combustion chamber (Institute of Power Engineering in Warsaw) with usage of Fibre Optical Measurement System (FOMS) are used in the paper. A conducted simulation proved that implementing GA and FOMS to the process is possible and limits the emission of harmful substatces in flue gases.

In this article we compare compression of flame pulsation signals based on Fourier transform, wavelet transform and wavelet packet transform. The results show efficiency of compressing based on cumulative energy of the same number of coefficients.

In the article, the processes of low-oxygen corrosion are discussed as well as the main reasons for continuous monitoring of chosen gases’ concentrations in the thin layer close to the walls inside the power boiler. We present application of the absorption spectroscopy in measurements of the above mentioned gas concentrations. Moreover the idea of a fiber-optic concentration analyzer of CO and O 2 in the considered gas layer, is presented.

In the article we present the idea of the data preprocessing in the optoelectronic measurement system for monitoring the industrial gas pollutants. A single optical measurement path can carry a big amount of data in an entirely parallel manner (e.g. spectral response of light in an absorbing media). To meet the requirements coming from optical system properties, the new algorithm called Local Discriminant Basis with Feature Selection - LDBFS is proposed. It's based on discrete wavelet transform and multidimensional data decomposition techniques. In order to assess the performance of the proposed method, the article presents the simulation results of data analysis of gas spectral absorption.

There no existing universal method of choosing a proper wavelet basis. In this article we present a methodology of choosing the adequate wavelet in detecting some of signals’ features which points to the change of the power burner working point.

In this paper we present the idea of the optoelectronic measurement system for monitoring the industrial gas pollutants. The system consists of an optical detection system, an optical fiber as a data transmission link, a spectrometer with linear diode array and a neural network unit for real-time spectral data processing. We paid main attention to the neural network structure and its properties for gas recognition and gas concentration estimation task. The article presents the new classification algorithm based on the selforganizing artificial neural network. The algorithm comes from the kohonen selforganizing neural net idea. It introduces the groups of winners and that is why, we call it Multi-Winners Selforganizing Kohonen Map - MWSOM. The behavior and fundamental featured of that classifier are presented and verified by comparison to other 'classical' classification algorithms.

We present the method of detection the kind of burned fuel in industrial conditions. Wavelet transforms were applied for the signals corresponding to pulsation of chosen flame zone.

We present application of continuous and discrete wavelet transform in detection of pulverized coal flame instabilities. Choosing the proper wavelet has been taken into consideration. In this case, possible area of application both continuous and discrete wavelet transform has also been discussed.

In the article we describe the possibility of utilization of the multichannel optical-fiber probe developed in our department as an optical-fiber pyrometer. Analytical approach is shown as well as some example measurements.

In power boiler control, it is very important do distinguish signals corresponding to different air/fuel ratios and different flames (pulverized coal, mazout). Since the signals obtained from flame monitoring systems are unstable, wavelet transform has been utilized in filtering these signals. Problems arise with choosing the most adequate wavelet to analyzed signal. In this paper, we investigate signals which reflects sudden cut off of mazout in industrial burner (pulverized coal is still present). Because amplitude measures are unreliable, we have been concentrated on 'frequency' measures. A method of choosing the proper wavelet and decomposition level have been proposed.

The introduction of low emission techniques of combustion caused side-effects like oxygen lean corrosion. It also enforced more precise management of technological air, better coal milling and application of devices for combustion process monitoring. In the article authors presented their own solution of optical fiber system for combustion quality evaluation, already operating on power boiler type OP-650. Its functionality was described together with selected results of measurements. Directions of further development of the system were also indicated.

In the article the preliminary solution and a concept of industrial version of the fibreoptic system for monitoring of fuel-oil burners in power boilers is described. It eliminates disadvantages of currently used systems and extends its diagnostic capabilities. Measurements made using the prototype monitoring system are also presented.

In the article we present application of wavelet adaptive filtering of output signal of fibre-optic flame monitoring system. It enables better distinction of output signals correspond to various types of fuels (mazout, coal) and improves detection of flame instabilities.

In this article we discuss the main directions of changes in organization of combustion process in industrial power boilers. We describe the fiber optic system permitting the measurement of flicker of the single coal-dust burner as well as the influence of the input conditions (primary air, secondary air) on changes of flicker. The solution operating in boiler in the `Kozienice' Power Plant was shown, as well as examples of measurement results made using a device built by authors. They confirmed the thesis that a flame flicker can be utilized for its quality evaluation.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

In this article we discuss the properties of autoregression (AR) and moving average (MA) processes, as well as non- parametrical and parametrical identification of their models describing real time-series. We have shown the principles of calculating one-step forecasts with the smallest average square error for real time series, which describe flame blinking in a coal burner working in a boiler of the 200 MW energetic block. We have calculated ARMA (p,q) and ARIMA (p,d,q) mixed models, which, in turn, helped us to calculate one-step forecasts. The results, in the form of a measured time series, with marked one-step forecasts, are shown in enclosed figures.

In this paper we describe an electrooptical sensor employing the Pockels effect. We also provide its analysis in order to determine its optical transmission as a function of the voltage applied and the influence of different temperatures on its parameters. Simulation results and the error analysis from the operation of a sensor made of a BSO (Bi12SiO20) crystal have also been demonstrated.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.