Advanced analysis and design methods for preparative chromatographic separation processes

Preparative liquid chromatography is one of the most selective separation techniques in the fine chemical, pharmaceutical, and food industries. Several process concepts have been developed and applied for improving the performance of classical batch chromatography. The most powerful approaches include various single-column recycling schemes, counter-current and cross-current multi-column setups, and hybrid processes where chromatography is coupled with other unit operations such as crystallization, chemical reactor, and/or solvent removal unit. To fully utilize the potential of stand-alone and integrated chromatographic processes, efficient methods for selecting the best process alternative as well as optimal operating conditions are needed. In this thesis, a unified method is developed for analysis and design of the following singlecolumn fixed bed processes and corresponding cross-current schemes: (1) batch chromatography, (2) batch chromatography with an integrated solvent removal unit, (3) mixed-recycle steady state recycling chromatography (SSR), and (4) mixed-recycle steady state recycling chromatography with solvent removal from fresh feed, recycle fraction, or column feed (SSR–SR). The method is based on the equilibrium theory of chromatography with an assumption of negligible mass transfer resistance and axial dispersion. The design criteria are given in general, dimensionless form that is formally analogous to that applied widely in the so called triangle theory of counter-current multi-column chromatography. Analytical design equations are derived for binary systems that follow competitive Langmuir adsorption isotherm model. For this purpose, the existing analytic solution of the ideal model of chromatography for binary Langmuir mixtures is completed by deriving missing explicit equations for the height and location of the pure first component shock in the case of a small feed pulse. It is thus shown that the entire chromatographic cycle at the column outlet can be expressed in closed-form. The developed design method allows predicting the feasible range of operating parameters that lead to desired product purities. It can be applied for the calculation of first estimates of optimal operating conditions, the analysis of process robustness, and the early-stage evaluation of different process alternatives. The design method is utilized to analyse the possibility to enhance the performance of conventional SSR chromatography by integrating it with a solvent removal unit. It is shown that the amount of fresh feed processed during a chromatographic cycle and thus the productivity of SSR process can be improved by removing solvent. The maximum solvent removal capacity depends on the location of the solvent removal unit and the physical solvent removal constraints, such as solubility, viscosity, and/or osmotic pressure limits. Usually, the most flexible option is to remove solvent from the column feed. Applicability of the equilibrium design for real, non-ideal separation problems is evaluated by means of numerical simulations. Due to assumption of infinite column efficiency, the developed design method is most applicable for high performance systems where thermodynamic effects are predominant, while significant deviations are observed under highly non-ideal conditions. The findings based on the equilibrium theory are applied to develop a shortcut approach for the design of chromatographic separation processes under strongly non-ideal conditions with significant dispersive effects. The method is based on a simple procedure applied to a single conventional chromatogram. Applicability of the approach for the design of batch and counter-current simulated moving bed processes is evaluated with case studies. It is shown that the shortcut approach works the better the higher the column efficiency and the lower the purity constraints are.

Adaptive MCMC methods with applications in environmental and geophysical models

This work presents new, efficient Markov chain Monte Carlo (MCMC) simulation methods for statistical analysis in various modelling applications. When using MCMC methods, the model is simulated repeatedly to explore the probability distribution describing the uncertainties in model parameters and predictions. In adaptive MCMC methods based on the Metropolis-Hastings algorithm, the proposal distribution needed by the algorithm learns from the target distribution as the simulation proceeds. Adaptive MCMC methods have been subject of intensive research lately, as they open a way for essentially easier use of the methodology. The lack of user-friendly computer programs has been a main obstacle for wider acceptance of the methods. This work provides two new adaptive MCMC methods: DRAM and AARJ. The DRAM method has been built especially to work in high dimensional and non-linear problems. The AARJ method is an extension to DRAM for model selection problems, where the mathematical formulation of the model is uncertain and we want simultaneously to fit several different models to the same observations. The methods were developed while keeping in mind the needs of modelling applications typical in environmental sciences. The development work has been pursued while working with several application projects. The applications presented in this work are: a winter time oxygen concentration model for Lake Tuusulanjärvi and adaptive control of the aerator; a nutrition model for Lake Pyhäjärvi and lake management planning; validation of the algorithms of the GOMOS ozone remote sensing instrument on board the Envisat satellite of European Space Agency and the study of the effects of aerosol model selection on the GOMOS algorithm.

Computational Evaluation of Print Unevenness According to Human Vision

Print quality and the printability of paper are very important attributes when modern printing applications are considered. In prints containing images, high print quality is a basic requirement. Tone unevenness and non uniform glossiness of printed products are the most disturbing factors influencing overall print quality. These defects are caused by non ideal interactions of paper, ink and printing devices in high speed printing processes. Since print quality is a perceptive characteristic, the measurement of unevenness according to human vision is a significant problem. In this thesis, the mottling phenomenon is studied. Mottling is a printing defect characterized by a spotty, non uniform appearance in solid printed areas. Print mottle is usually the result of uneven ink lay down or non uniform ink absorption across the paper surface, especially visible in mid tone imagery or areas of uniform color, such as solids and continuous tone screen builds. By using existing knowledge on visual perception and known methods to quantify print tone variation, a new method for print unevenness evaluation is introduced. The method is compared to previous results in the field and is supported by psychometric experiments. Pilot studies are made to estimate the effect of optical paper characteristics prior to printing, on the unevenness of the printed area after printing. Instrumental methods for print unevenness evaluation have been compared and the results of the comparison indicate that the proposed method produces better results in terms of visual evaluation correspondence. The method has been successfully implemented as ail industrial application and is proved to be a reliable substitute to visual expertise.

Diskreettiaikainen liukuvan moodin säätö kiinteäoksidipolttokennon DC-tasonnostossa

Huoli ympäristön tilasta ja fossiilisten polttoaineiden hinnan nousu ovat vauhdittaneet tutkimusta uusien energialähteiden löytämiseksi. Polttokennot ovat yksi lupaavimmista tekniikoista etenkin hajautetun energiantuotannon, varavoimalaitosten sekä liikennevälineiden alueella. Polttokenno on tehonlähteenä kuitenkin hyvin epäideaalinen, ja se asettaa tehoelektroniikalle lukuisia erityisvaatimuksia. Polttokennon kytkeminen sähköverkkoon on tavallisesti toteutettu käyttämällä galvaanisesti erottavaa DC/DC hakkuria sekä vaihtosuuntaajaa sarjassa. Polttokennon kulumisen estämiseksi tehoelektroniikalta vaaditaan tarkkaa polttokennon lähtövirran hallintaa. Perinteisesti virran hallinta on toteutettu säätämällä hakkurin tulovirtaa PI (Proportional and Integral) tai PID (Proportional, Integral and Derivative) -säätimellä. Hakkurin epälineaarisuudesta johtuen tällainen ratkaisu ei välttämättä toimi kaukana linearisointipisteestä. Lisäksi perinteiset säätimet ovat herkkiä mallinnusvirheille. Tässä diplomityössä on esitetty polttokennon jännitettä nostavan hakkurin tilayhtälökeskiarvoistusmenetelmään perustuva malli, sekä malliin perustuva diskreettiaikainen integroiva liukuvan moodin säätö. Esitetty säätö on luonteeltaan epälineaarinen ja se soveltuu epälineaaristen ja heikosti tunnettujen järjestelmien säätämiseen.

Tavaramerkin suoja-alan laajuus Suomessa ja Kiinassa

Tutkielman tarkoituksena on perehtyä siihen, kuinka laajasti tavaramerkin haltija voi kieltää toista elinkeinoharjoittajaa käyttämästä samaa tai samankaltaista merkkiä, kun sitä käytetään samoissa, samankaltaisissa tai jopa täysin erilaisissa tavaroissa tai palveluissa. Merkin haltijan kielto-oikeuden laajuuteen paneudutaan tutkimalla ensiksi EU:n tavaramerkkidirektiiviä ja Suomen tavaramerkkilakia ja oikeuskäytäntöjä. Tämän jälkeen tutkitaan, kuinka laaja kielto-oikeus merkin haltijalla on Kiinassa. Pääasiallinen tutkimusmetodi on lainopillinen, mutta myös oikeusvertailua tehdään Suomen ja Kiinan välillä. Tavaramerkin suojaamisessa on Suomessa selkeästi havaittavissa Chicagon koulukunnan teorian hyväksyminen, joka tavaramerkkioikeuteen sovellettuna korostaa merkin haltijan laajaa suojaa. Teorian mukaan tavaramerkin brandiksi luomiseen liittyviä investointeja pitää suojata ja estää sen ansioton hyödyntäminen. Päinvastaista teoriaa edustaa Harvardin koulukunta, jonka teorian piirteitä on havaittavissa Kiinan tavaramerkkioikeudessa. Se korostaa tavaramerkin kapeaa suojaa. Sallimalla kilpailijoiden jäljitellä tunnettua tavaramerkkiä parannetaan kilpailijan asemaa markkinoilla. Toisaalta ulkomaiset merkin haltijat kohtaavat Kiinassa myös paljon ei-tavaramerkkioikeudellisia ongelmia, jotka vaikeuttavat tavaramerkin suojaamista Kiinan markkinoilla.

Calibration and simulations of SIXS-P's response to energetic particles

The Solar Intensity X-ray and particle Spectrometer (SIXS) on board BepiColombo's Mercury Planetary Orbiter (MPO) will study solar energetic particles moving towards Mercury and solar X-rays on the dayside of Mercury. The SIXS instrument consists of two detector sub-systems; X-ray detector SIXS-X and particle detector SIXS-P. The SIXS-P subdetector will detect solar energetic electrons and protons in a broad energy range using a particle telescope approach with five outer Si detectors around a central CsI(Tl) scintillator. The measurements made by the SIXS instrument are necessary for other instruments on board the spacecraft. SIXS data will be used to study the Solar X-ray corona, solar flares, solar energetic particles, the Hermean magnetosphere, and solar eruptions. The SIXS-P detector was calibrated by comparing experimental measurement data from the instrument with Geant4 simulation data. Calibration curves were produced for the different side detectors and the core scintillator for electrons and protons, respectively. The side detector energy response was found to be linear for both electrons and protons. The core scintillator energy response to protons was found to be non-linear. The core scintillator calibration for electrons was omitted due to insufficient experimental data. The electron and proton acceptance of the SIXS-P detector was determined with Geant4 simulations. Electron and proton energy channels are clean in the main energy range of the instrument. At higher energies, protons and electrons produce non-ideal response in the energy channels. Due to the limited bandwidth of the spacecraft's telemetry, the particle measurements made by SIXS-P have to be pre-processed in the data processing unit of the SIXS instrument. A lookup table was created for the pre-processing of data with Geant4 simulations, and the ability of the lookup table to provide spectral information from a simulated electron event was analysed. The lookup table produces clean electron and proton channels and is able to separate protons and electrons. Based on a simulated solar energetic electron event, the incident electron spectrum cannot be determined from channel particle counts with a standard analysis method.

Variational ensemble Kalman filtering applied to data assimilation problems in computational fluid dynamics

One challenge on data assimilation (DA) methods is how the error covariance for the model state is computed. Ensemble methods have been proposed for producing error covariance estimates, as error is propagated in time using the non-linear model. Variational methods, on the other hand, use the concepts of control theory, whereby the state estimate is optimized from both the background and the measurements. Numerical optimization schemes are applied which solve the problem of memory storage and huge matrix inversion needed by classical Kalman filter methods. Variational Ensemble Kalman filter (VEnKF), as a method inspired the Variational Kalman Filter (VKF), enjoys the benefits from both ensemble methods and variational methods. It avoids filter inbreeding problems which emerge when the ensemble spread underestimates the true error covariance. In VEnKF this is tackled by resampling the ensemble every time measurements are available. One advantage of VEnKF over VKF is that it needs neither tangent linear code nor adjoint code. In this thesis, VEnKF has been applied to a two-dimensional shallow water model simulating a dam-break experiment. The model is a public code with water height measurements recorded in seven stations along the 21:2 m long 1:4 m wide flume’s mid-line. Because the data were too sparse to assimilate the 30 171 model state vector, we chose to interpolate the data both in time and in space. The results of the assimilation were compared with that of a pure simulation. We have found that the results revealed by the VEnKF were more realistic, without numerical artifacts present in the pure simulation. Creating a wrapper code for a model and DA scheme might be challenging, especially when the two were designed independently or are poorly documented. In this thesis we have presented a non-intrusive approach of coupling the model and a DA scheme. An external program is used to send and receive information between the model and DA procedure using files. The advantage of this method is that the model code changes needed are minimal, only a few lines which facilitate input and output. Apart from being simple to coupling, the approach can be employed even if the two were written in different programming languages, because the communication is not through code. The non-intrusive approach is made to accommodate parallel computing by just telling the control program to wait until all the processes have ended before the DA procedure is invoked. It is worth mentioning the overhead increase caused by the approach, as at every assimilation cycle both the model and the DA procedure have to be initialized. Nonetheless, the method can be an ideal approach for a benchmark platform in testing DA methods. The non-intrusive VEnKF has been applied to a multi-purpose hydrodynamic model COHERENS to assimilate Total Suspended Matter (TSM) in lake Säkylän Pyhäjärvi. The lake has an area of 154 km2 with an average depth of 5:4 m. Turbidity and chlorophyll-a concentrations from MERIS satellite images for 7 days between May 16 and July 6 2009 were available. The effect of the organic matter has been computationally eliminated to obtain TSM data. Because of computational demands from both COHERENS and VEnKF, we have chosen to use 1 km grid resolution. The results of the VEnKF have been compared with the measurements recorded at an automatic station located at the North-Western part of the lake. However, due to TSM data sparsity in both time and space, it could not be well matched. The use of multiple automatic stations with real time data is important to elude the time sparsity problem. With DA, this will help in better understanding the environmental hazard variables for instance. We have found that using a very high ensemble size does not necessarily improve the results, because there is a limit whereby additional ensemble members add very little to the performance. Successful implementation of the non-intrusive VEnKF and the ensemble size limit for performance leads to an emerging area of Reduced Order Modeling (ROM). To save computational resources, running full-blown model in ROM is avoided. When the ROM is applied with the non-intrusive DA approach, it might result in a cheaper algorithm that will relax computation challenges existing in the field of modelling and DA.

On Modelling, System Identification and Control of Servo-Systems with a Flexible Load

The present study was done with two different servo-systems. In the first system, a servo-hydraulic system was identified and then controlled by a fuzzy gainscheduling controller. The second servo-system, an electro-magnetic linear motor in suppressing the mechanical vibration and position tracking of a reference model are studied by using a neural network and an adaptive backstepping controller respectively. Followings are some descriptions of research methods. Electro Hydraulic Servo Systems (EHSS) are commonly used in industry. These kinds of systems are nonlinearin nature and their dynamic equations have several unknown parameters.System identification is a prerequisite to analysis of a dynamic system. One of the most promising novel evolutionary algorithms is the Differential Evolution (DE) for solving global optimization problems. In the study, the DE algorithm is proposed for handling nonlinear constraint functionswith boundary limits of variables to find the best parameters of a servo-hydraulic system with flexible load. The DE guarantees fast speed convergence and accurate solutions regardless the initial conditions of parameters. The control of hydraulic servo-systems has been the focus ofintense research over the past decades. These kinds of systems are nonlinear in nature and generally difficult to control. Since changing system parameters using the same gains will cause overshoot or even loss of system stability. The highly non-linear behaviour of these devices makes them ideal subjects for applying different types of sophisticated controllers. The study is concerned with a second order model reference to positioning control of a flexible load servo-hydraulic system using fuzzy gainscheduling. In the present research, to compensate the lack of dampingin a hydraulic system, an acceleration feedback was used. To compare the results, a pcontroller with feed-forward acceleration and different gains in extension and retraction is used. The design procedure for the controller and experimental results are discussed. The results suggest that using the fuzzy gain-scheduling controller decrease the error of position reference tracking. The second part of research was done on a PermanentMagnet Linear Synchronous Motor (PMLSM). In this study, a recurrent neural network compensator for suppressing mechanical vibration in PMLSM with a flexible load is studied. The linear motor is controlled by a conventional PI velocity controller, and the vibration of the flexible mechanism is suppressed by using a hybrid recurrent neural network. The differential evolution strategy and Kalman filter method are used to avoid the local minimum problem, and estimate the states of system respectively. The proposed control method is firstly designed by using non-linear simulation model built in Matlab Simulink and then implemented in practical test rig. The proposed method works satisfactorily and suppresses the vibration successfully. In the last part of research, a nonlinear load control method is developed and implemented for a PMLSM with a flexible load. The purpose of the controller is to track a flexible load to the desired position reference as fast as possible and without awkward oscillation. The control method is based on an adaptive backstepping algorithm whose stability is ensured by the Lyapunov stability theorem. The states of the system needed in the controller are estimated by using the Kalman filter. The proposed controller is implemented and tested in a linear motor test drive and responses are presented.

Analysis of torque and speed ripple producing non-idealities of frequency converters in electric drives

Electric motors driven by adjustable-frequency converters may produce periodic excitation forces that can cause torque and speed ripple. Interaction with the driven mechanical system may cause undesirable vibrations that affect the system performance and lifetime. Direct drives in sensitive applications, such as elevators or paper machines, emphasize the importance of smooth torque production. This thesis analyses the non-idealities of frequencyconverters that produce speed and torque ripple in electric drives. The origin of low order harmonics in speed and torque is examined. It is shown how different current measurement error types affect the torque. As the application environment, direct torque control (DTC) method is applied to permanent magnet synchronous machines (PMSM). A simulation model to analyse the effect of the frequency converter non-idealities on the performance of the electric drives is created. Themodel enables to identify potential problems causing torque vibrations and possibly damaging oscillations in electrically driven machine systems. The model is capable of coupling with separate simulation software of complex mechanical loads. Furthermore, the simulation model of the frequency converter's control algorithm can be applied to control a real frequency converter. A commercial frequencyconverter with standard software, a permanent magnet axial flux synchronous motor and a DC motor as the load are used to detect the effect of current measurement errors on load torque. A method to reduce the speed and torque ripple by compensating the current measurement errors is introduced. The method is based on analysing the amplitude of a selected harmonic component of speed as a function oftime and selecting a suitable compensation alternative for the current error. The speed can be either measured or estimated, so the compensation method is applicable also for speed sensorless drives. The proposed compensation method is tested with a laboratory drive, which consists of commercial frequency converter hardware with self-made software and a prototype PMSM. The speed and torque rippleof the test drive are reduced by applying the compensation method. In addition to the direct torque controlled PMSM drives, the compensation method can also beapplied to other motor types and control methods.

Problems of the architecture design in the system integration

This thesis studies the problems and their reasons a software architect faces in his work. The purpose of the study is to search and identify potential factors causing problens in system integration and software engineering. Under a special interest are non-technical factors causing different kinds of problems. Thesis was executed by interviewing professionals that took part in e-commerce project in some corporation. Interviewed professionals consisted of architects from technical implementation projects, corporation's architect team leader, different kind of project managers and CRM manager. A specific theme list was used as an guidance of the interviews. Recorded interviews were transcribed and then classified using ATLAS.ti software. Basics of e-commerce, software engineering and system integration is described too. Differences between e-commerce and e-business as well as traditional business are represented as are basic types of e-commerce. Software's life span, general problems of software engineering and software design are covered concerning software engineering. In addition, general problems of the system integration and the special requirements set by e-commerce are described in the thesis. In the ending there is a part where the problems founded in study are described and some areas of software engineering where some development could be done so that same kind of problems could be avoided in the future.

Non-wood massojen vedenpoiston arvioiminen märkäpuristuksessa

Yksivuotisten kasvien (non-wood) kuitua verrataan usein lehtipuukuituihin. Käytetyimpiä non-wood kasveja ovat vehnän olki, bambu, järviruoko ja bagassi. Non-wood massan erottaa puumassasta kuitenkin korkea silikaattipitoisuus sekä parenkyymisolupitoisuus, joka antaa massalle korkean hienoainepitoisuuden. Tämä yhdessä korkean hemiselluloosapitoisuuden ja lyhyen kuidun pituuden kanssa heikentävät voimakkaasti non-wood massan vedenpoisto-ominaisuuksia. Non-wood kuidulla voidaan korvata lehtipuumassaa hienopapereissa. Non-wood kuitu antaa paperille hyvän opasiteetin, korkean valonsirontakertoimen sekä sileän painopinnan. Massaan lisättävä pitkäkuituinen havupuumassa parantaa ajetta¬vuutta paperikoneella ja helpottaa massan vedenpoistoa. Non-wood massan vedenpoistoa voidaan tehostaa esimerkiksi poistamalla osa hienoaineesta, käyttämällä non-wood massalle sopivaa keittotapaa sekä käyttämällä märkä¬puristuksessa pitkänippityyppistä puristinratkaisua. Myös non-wood kuidun kuivaaminen parantaa vedenpoistoa. Tässä tutkimuksessa kirjallisuusosassa keskityttiin yleisimpiin paperin valmistuksessa käytettäviin non-wood kuidun lähteisiin, märkäpuristuksen teoriaan ja tapoihin tehostaa vedenpoistoa. Kokeellisessa osassa tutkittiin vehnänolkimassan käyttäytymistä märkäpuristuksessa erilaisten ominaisuuksien pohjalta. Tutkimuksen kohteena oli non-wood massan keittotapa (hapan/alkali), hienoainepitoisuus, silikaattipitoisuus sekä kuivattu/kuivaamaton kuitu. Vertailun vuoksi tutkimuksessa oli mukana myös yksi järviruokomassa. Tuloksista huomataan, että non-wood massan vedenpoistoon vaikuttaa hienoainepitoisuus, kuidun kuivaus sekä massan valmistustapa. Järviruokomassan veden¬poisto on tehokkaampaa kuin vehnänolkimassan paremman kuitu¬koostumuksensa takia. Jos hienopaperimassassa korvataan lehtipuumassaa non-wood kuidulla maksimissaan 40 %, massan vedenpoistoa voidaan hyvin arvioida erilaisten suotautuvuusmittojen, kuten freeneksen, vedenpidätyskyvyn ja suotautumisajan, avulla.

Sensory and Non-sensory Factors Behind the Liking and Choice of Healthy Food Products

A healthy and balanced diet can reduce health problems, such as overweight and metabolic syndrome. In general, people have a considerably good knowledge of what constitutes a healthy diet and how they could achieve it with their food choices. Besides, people argue that health is among their top five food choice motives. Nevertheless, the prevalence of overweight is increasing and other food choice motives, such as taste, seem to conflict with the health. Liking for food does not necessarily determine acceptance alone, thus several non-sensory factors, such as brand, country of origin and nutrition claim, can also influence. Moreover, consumers are individuals in how they prioritize sensory and nonsensory factors of foods, but e.g. increasing age, female gender and health concern have been connected to a more health-oriented dietary behaviour. To sum up, identifying different factors that can increase the liking and consumption of healthy food is essential in order to develop more attractive healthful food products. Adding vitamins, minerals, fibre or other ingredients to a food product can be used to enrich the nutritional quality of the products. However, this may be difficult in practice as regards the sensory quality and pleasantness of the foods. Generally, consumers are not willing to compromise on taste in food. On the other hand, consumers are very heterogeneous in their likings, and their personal values and attitudes may interact with preferences for specific sensory characteristics. The aims of this study were to investigate the effects of intrinsic product characteristics on sensory properties and hedonic responses; to determine the impact of few non-sensory factors; and to examine the interaction between sensory and non-sensory factors with consumers’ demographics, values and attitudes in liking of healthy model foods. The results showed that product composition influenced sensory quality and had an effect on hedonic responses. Adding flaxseed to bakery products showed a significant improvement in the nutritional quality without negative effects on sensory properties. On the other hand, the fortification of wellness beverages with vitamins and minerals may impart off-flavours. In general, sweetness of yoghurts, freshness of wellness beverages and low intensity of rye bread flavour appealed to consumers. Information about the domestic origin of yoghurts and claiming a specific function for wellness beverages enhanced liking. However, consumers who were more concerned about their health and considered natural content as an important food choice motive, rated sourer and less sweet yoghurts and wellness beverages as more pleasant. In addition, interest in health increased the consumption of rye breads and other whole grain breads among adolescents. The results showed that the optimal product quality in terms of intrinsic and extrinsic factors differs between individual consumers, and personal values and food choice motives can be connected to preferences for specific sensory characteristics of foods. This indicates that each food product needs to be considered in relation to its specific market niche, and to which segment of consumer will respond most positively to its characteristics.

Utilization of retention chemicals in non-wood containing furnishes

The usage of the non-wood pulps in furnishes for various paper grades is the real alternative for substitution of wood fibres in the papermaking. This is especially important now, when the prices for wood are increasing and forest resources are depleting in many regions of our planet. However, there are several problems associated with utilization of such pulps. In terms of the papermaking process one of the main problems is the poor dewatering of the non-wood pulps. This problem can be partially solved by means of retention aids. In the literature part were described technological features of the non-wood pulps as the raw materials for paper production. Moreover, overviews of the retention chemicals and methods for retention measurement were done; special attention was paid to the mechanisms of retention and drainage. Finally, factors affecting on the drainage and retention of non-wood pulps were considered holistically. Particular emphasis was put on the possibility of enzyme treatment for drainage improvement. It was stated that retention aids can significantly improve dewatering of non-wood pulps. In the experimental part the goal was to investigate influence of various microparticle retention aids on the drainage, retention and formation of furnish containing wheat straw pulp, obtained by novel pulping process (Formico™Fib). The parallel test were performed with reference furnish containing only wood pulps. It was found that Bentonite-CPAM retention aid can significantly improve drainage and retention; however formation seems be suffer from such additives. It was stated that performance of the Silica-Starch retention aid significantly depends on the starch dosing sequence and wet-end conditions; this system have shown better formation than other tested retention aids. Silica-CPAM retention aid have provided comparable results in retention and drainage with Bentonite-CPAM, while Silica-starch did not improve dewatering and yielded in lowest filler retention among other aids. Ultimately, optimal dosages for the tested retention chemicals have been suggested.

Uusperheen voimavarat ja lasten hyvinvointi

The resources of the step family and the children’s well-being The present study investigates children's well-being in stepfamilies and fac¬tors, both external and internal, that are related to the children's well-being. Of the external factors, the study focuses on factors related to the structure of the stepfamily, parents' education, socio-economic status and factors related to work, livelihood and living conditions. The internal resources include the general functioning of the family, parenthood and parenting, family support networks and issues that the stepfamilies themselves consider important. Another important resource in a stepfamily is a functioning network of human relationships, which in the present study is approached from the maternal viewpoint. Changing family relations are considered a potential threat to the children's well-being. Therefore, in addition to looking into the stepfamily's resources, the other important goal of the study is to explore other factors potentially related to the well-being of children living in stepfamilies. In view of the stepfamily's resources, it is important to explore how the functioning of the relationships network is linked with the child's well-being. The study employs survey and interview data. The survey data (n=2236) are part of national survey data on the well-being of families and children and factors impacting them which were gathered as part of ”Origins of Exclusion in Early Childhood”, a research project carried out in 2002. The data consists of 667 stepfamilies. The interview data consists of interviews with 24 parents in stepfamilies. In the study, the analyses of survey and interview data are combined. Both descriptive statistical analyses and multivariate methods are employed. Content analysis is employed in the analysis of the interview data. The results indicate that the stepfamilies’ resources in general but their external resources in particular differed from those of the nuclear and single-parent families. The level of education and the socio-economic status of the stepfamily parents were somewhat lower than those of the nuclear family parents. The differences in relation to single-parent families were primarily related to the better economic status of the stepfamilies. The analysis of internal resources showed relatively minor differences: the stepfamilies assessed themselves a somewhat better general functioning of the family than did the nuclear families. Parenting issues caused more disagreement in stepfamilies than in nuclear families. The analysis of the functioning of the human relations in stepfamilies showed that the stepfamily mothers experienced the external relationships of the family (e.g., between the child and the absent father) as significantly more problematic than the relationships within the stepfamily. Living in a stepfamily thus challenges the functioning of the relationship between the child and the absent father. As a result of the analysis of the relationships networks in the stepfamilies, three groups were formed. One group had the nuclear family as an ideal goal, another valued an extended family composed of a variety of relationships, and the third one appreciated a strong intimate relationship between the parents. In the present study, the most common group was the multi-relationship, extended type of stepfamily. In conclusion, living in a stepfamily does not seem to pose a risk to the child’s well-being, but it may influence the family’s resources and thus have an indirect effect on the child’s well-being. In view of the resources of the stepfamily, the child’s well-being was best supported by a functioning network of human relationships in the stepfamily: there was a distinct connection with the children’s problems and the non-functioning of the relationships network. According to the mothers, the internal relationships in the stepfamily seemed to be more important than the external relationships of the family. A child’s functioning relationship with the absent father can be viewed as a positive resource, supporting the child’s well-being in the stepfamily.

Keskusteluja vuokratyöstä. Vuokratyön diskursiivinen rakentuminen Suomessa

1990-luvun alussa lainsäädäntö ja työmarkkinajärjestöt määrittelivät Suomessa, että vuokratyötä tuli käyttää vain tilapäiseen työvoimatarpeeseen, esimerkiksi sijaisuuksiin ja ruuhkahuippuihin. Joillakin aloilla vuokratyö oli työnantajien ja työntekijöiden yhteissopimuksella kielletty. Vaikka vuokratyösuhteet saivat jo 1980-luvulla niin Suomessa kuin kansainvälisestikin maineen työsuhdekeinotteluna, alkoi vuokratyön määrä Suomessa kasvaa 1990-luvun puolivälissä ja erityisesti tultaessa 2000-luvulle. Suomalaiset akateemiset tutkijat eivät ole juuri vuokratyöstä kiinnostuneet. Aiemmat, harvalukuiset tutkimukset ovat keskittyneet lähinnä työyhteisöjen ja työntekijöiden kokemuksiin sekä vuokratyön työehtoihin. Vuokratyö ymmärretäänkin edelleen lähinnä työntekijän subjektiivisena kokemuksena. Vuokratyössä on kuitenkin kysymys paitsi kokemuksista, myös yhteiskunnallisesta valtakamppailusta, jossa diskursiivisin keinoin pyritään vaikuttamaan ilmiöön nimeltä vuokratyö, laajemmin ilmiöön nimeltä työmarkkinat, sekä toisaalta kansalaisten käsityksiin työelämän ”normaalista”. Käsillä oleva tutkimus laajentaa ymmärrystä vuokratyöstä tarkastelemalla ilmiötä lainsäädännön, uutisoinnin ja markkinoinnin rakentamien julkisten käsitysten ja merkityksenantojen kautta. Teoreettisena viitekehyksenä käytän hallinnan ja työprosessin säätelyn teoriaperinteitä. Se, miten työmarkkinoiden muutosta ja uusia työsuhdemuotoja politiikassa, mediassa, lainsäädännössä, tai työpaikan kahvipöytäkeskusteluissa perustellaan ja tehdään ymmärrettäväksi, on samalla työelämään kiinnitettävien arvojen, merkitysten ja toimijuuksien luomista, rajaamista ja kuvailua. Työelämäpuheessa ei siis ole kyse vain talouden lainalaisuuksista, kansantalouden toimivuudesta, tai yritysten kilpailukyvystä, vaan myös ja erityisesti niiden toimijoiden luomisesta, määrittelemisestä ja legitimoimisesta, jotka työelämän kentällä saavat toimia ja tulevat palkituiksi. Säätelyn ja hallinnan näkökulmasta on relevanttia tarkastella millaisilla käsitteillä ja merkityksillä vuokratyötä ilmiönä rakennetaan . Tutkimuskysymyksinä esitän: 1) Miten ja millä perusteilla vuokratyöstä rakennettiin Suomessa legitiimi tapa työllistää ja työllistyä? 2) Millaisia työntekijäideaaleja vuokratyöhön liittyvissä keskusteluissa rakennetaan? Tutkimusaineistona tarkastelen lainsäädäntöön liittyviä dokumentteja, Helsingin Sanomien uutisointia, vuokratyöyritysten markkinointimateriaaleja, sekä vuokratyöyritysten edustajien haastatteluita. Analyysimenetelmänä käytän kriittistä diskurssianalyysia. Tämä menetelmä mahdollistaa puheen ja dokumenttien tarkastelun sosiaalisena toimintana, jolla eri toimijat pyrkivät osallistumaan yhteiskunnassa hyväksyttyjen ja tunnustettujen käsitysten ja toimintavaihtoehtojen rakentamis-, tulkinta- ja määrittelyprosesseihin. Tutkimukseni päätuloksena esitän, että vuokratyöstä muodostui legitiimi tapa työllistää Suomessa 1990-luvulla, koska vuokratyö käsitteellistettiin sekä lainsäädännön että median diskursseissa ennen kaikkea ratkaisuksi työttömyyteen. Toisaalta vuokratyö käsitteellistettiin vain marginaalisten työntekijäryhmien (naiset ja opiskelijat) rooliksi, jolloin se ei liittynyt miesvaltaisten työpaikkojen arkeen. Ratkaisuna työttömyyteen vuokratyö myös samalla luonnollistettiin osaksi yleisempää työmarkkinakehitystä, jolle ”kukaan ei voi mitään”. 2000-luvulla vuokratyö jatkoi voittokulkuaan ja rakentui pysyväksi ilmiöksi, koska työlainsäädännön uudistus institutionalisoi vuokratyön työehtosopimusmenettelyyn, jolloin sen ”salonkikelpoisuus” ja normaalius vahvistettiin. Vaikka työehtosopimusasia oli ratkaisuna merkittävä, nousi vuokratyön osalta itse työehtosopimus tärkeämmäksi kuin sen sisältö. Työehtosopimuksilla ei kuitenkaan pystytty vaikuttamaan esimerkiksi vuokratyöntekijän olemattomaan työsuhdeturvaan. Lisäksi työnantajapuhe käsitteellistää vuokratyön 2000-luvulla ennen kaikkea työmarkkinavaihtoehdoksi, vapautta ja monipuolisia työkokemuksia tarjoavaksi työmarkkinoiden katalysaattoriksi. Vuokratyö on tässä merkitysavaruudessa työntekijöille ”vain” yksi tapa työllistyä ja löytää oma tiensä työmarkkinoille, ei suinkaan työnantajien sanelema pakko. Työntekijöihin kohdistuva hallintapuhe niin mediassa kuin työnantajien haastatteluissakin pyrkii puolestaan rakentamaan ideaalityöntekijäkuvaksi yrittäjämäisen oman elämänsä toimitusjohtajan. Työnantajien diskursseissa kaikuvatkin työntekijään kohdistuva vaatimus itse itsensä ohjaamisesta sekä työntekijäidentiteetin muotoilemisesta joustavuutta, sopeutuvuutta, vaihtelua ja jatkuvaa muutosta vähintäänkin sietäväksi, mutta mieluiten näitä ominaisuuksia jopa aktiivisesti hakevaksi ja arvostavaksi. Työmarkkinoiden toimijana on nimenomaisesti yksilö, jonka mahdollisuudet menestyä ovat vain ja ainoastaan hänen omissa käsissään. Työntekijän roolin korostaminen aktiivisena toimijana ja vuokratyöstä ”oikeita”, norminmukaisia sisältöjä löytävänä pärjääjänä on diskursiivisesti hallittua yritystä ohjata työntekijöitä näkemään sekä itsensä tietynlaisina toimijoina että työmarkkinat tietyllä tavalla toimivina. Vuokratyössä ei ole kyse vain työntekijöiden yksilöllisistä tai yksittäisistä kokemuksista. Vuokratyö on yhteiskunnallisen merkityskamppailun tulos, jossa käyttövoimana ovat toimineet hallinnalliset ja säätelyyn pyrkivät käsitteellistykset työllisyydestä, yksilön valinnasta ja koko yhteiskunnan edusta. Hallinnan ja säätelyn näkökulmasta katsottuna vuokratyö on myös merkinnyt säätelyn liukumista tasa-arvoa, yhdenmukaista kohtelua ja työntekijän suojelua korostavasta viranomaisten ja poliittisten toimijoiden suorittamasta työmarkkinoiden kollektiivisesta säätelystä työnantajien ylläpitämään työntekijän persoonan ja käyttäytymisen hegemoniseen, yksilölliseen säätelyyn.