Continuous counter current extraction (CCCE) or dual flow counter current chromatography (DFCCC) is a promising technique where components can be separated continuously by two liquid phases that flow in opposite directions through a continuous length of coiled tubing. Specially designed end connectors and a coil planet centrifuge allow each respective phase to be pumped into each end of the tubing and the other phase to elute at each opposite end. In this thesis the feasibility and the mechanics of CCCE are investigated using stroboscopic photography on an experimental rig and a specially built pilot-scale CCCE centrifuge. The mechanics of the hydrodynamics in the coil was investigated systematically by comparing the measured volumes with photographic images of the process. This investigation revealed that the phases are not distributed evenly throughout the coil, which was previously assumed, but that there is a transition area where the phases switch from mainly upper phase at the head end of the tubing to mainly lower phase at the tail end. This means that the sample encounter three different phase distribution zones in the coil. At the head the upper phase is the dominant phase with a small volume of lower phase running through. At the tail the reverse situation is found and lower phase is dominant. The third zone is a short segment of the coil where there is a transition between the dominant phase conditions that exist at each end. The position of the transition zone and the volume of the other two zones are profoundly affected by the relative flow rates of the two phases. This work indicates that the volume distribution in the coil is affected most by the upper phase flow rate. The pilot-scale CCCE centrifuge was used to successfully separate industrially supplied samples. Crude reaction liquor was processed in both batch and continuous modes achieving the separation of the multi-component mixture into two groups. Changing the flow rate combinations changed the location of elution of some of the components in the mixture. Separation efficiency was maintained even when sample loading was increased. The separations were shown to be predictable with the dual flow theoretical model.

In times of demand shocks, when quantitative forecasting based on historical time series becomes obsolete, the only information about future demand is "advance demand information", i.e. interpreting early customer bookings as an indicator of not yet known demand. This paper deals with a forecasting method which selects the optimal forecasting model type and the level of integration of advance demand information, depending on the patterns of the particular time series. This constitutes the applicability of the procedure within an industrial application where a large number of time series is automatically forecasted in a flexible and data-driven way. The architecture of such a planning system is explained and using real-world data from a make-to-order industry it is shown that the system is flexible enough to cover different demand patterns and is well-suited to forecast demand shocks. (authors' abstract)

No description available.

Ces travaux de recherche ont pour ambition de contribuer à la problématique de la classification d’images de documents. Plus précisément, ces travaux tendent à répondre aux problèmes rencontrés par des sociétés de numérisation dont l’objectif est de mettre à disposition de leurs clients une version numérique des documents papiers accompagnés d’informations qui leurs sont relatives. Face à la diversité des documents à numériser, l’extraction d’informations peut s’avérer parfois complexe. C’est pourquoi la classification et l’indexation des documents sont très souvent réalisées manuellement. Ces travaux de recherche ont permis de fournir différentes solutions en fonction des connaissances relatives aux images que possède l’utilisateur ayant en charge l’annotation des documents.Le premier apport de cette thèse est la mise en place d’une méthode permettant, de manière interactive, à un utilisateur de classer des images de documents dont la nature est inconnue. Le second apport de ces travaux est la proposition d’une technique de recherche d’images de documents par l’exemple basée sur l’extraction et la mise en correspondance de points d’intérêts. Le dernier apport de cette thèse est l’élaboration d’une méthode de classification d’images de documents utilisant les techniques de sacs de mots visuels. / The aim of this research is to contribute to the document image classification problem. More specifically, these studies address digitizing company issues which objective is to provide the digital version of paper document with information relating to them. Given the diversity of documents, information extraction can be complex. This is why the classification and the indexing of documents are often performed manually. This research provides several solutions based on knowledge of the images that the user has. The first contribution of this thesis is a method for classifying interactively document images, where the content of documents and classes are unknown. The second contribution of this work is a new technique for document image retrieval by giving one example of researched document. This technique is based on the extraction and matching of interest points. The last contribution of this thesis is a method for classifying document images by using bags of visual words techniques.

<p>This thesis summarizes the equations, algorithms and design decisions necessary for dynamic simulation of flexible bodies with moving contacts. The assumed general shape function approach is also presented. The approach is expected to be computationally less expensive than FEM approaches and easier to use than other reduction techniques. Additionally, the described technique enables studies of the residual stress release during grinding of flexible bodies.</p><p>The overall software system design for a flexible multi-body simulation system BEAST is presented and the specifics of the flexible modeling is specially addressed. An industrial application example is also described in the thesis. The application presents some results from a case where the developed system is used for simulation of flexible ring grinding with material removal.</p> / Report code: LiU-TEK-LIC-2002:62.

Abstract During the last decades significant changes in the buying behavior of customers can be observed. While in former days price sensitivity lead to more uniformed products, in present days manifold high-quality products and customization with reasonable prices and rapid delivery are demanded. As a consequence, the industry asks for manufacturing systems which allow for fast ramp-up, multi-variant production and rapid adaptability. In this environment, several scientific approaches such as agent-based and holonic manufacturing systems have been investigated within the last years. In order to cover all aspects of the foreseen future demands, the architectures for such systems are very complex and the system’s entities are characterized by very flexible behavior. Hence, the efforts for their implementation are rather high and the systems tend to exhibit non-deterministic behavior. Furthermore, the top down approach of most systems leads to a complete re-organization of the factory management. As a consequence the acceptance for such systems in real industrial environment at present day is very limited. Therefore, the objective of this thesis is to develop an architecture for flexible manufacturing systems which allows for easy take-up in the industry. It is based on a bottom-up approach with a new kind of flexible, intelligent shop-floor components called Manufactrons. The architecture covers all layers of traditional factory organization with special emphasis on the shop floor organization. The approach and results are based on the research activities of the European Research Project XPRESS in which representatives of three major industry branches collaborated in order to find a solution for their future demands on flexible manufacturing systems. The architecture has been implemented in the context of XPRESS in aerospace, automotive and electrical industry. The tests show the feasibility of the approach. The capability for a smooth integration of the new approach into existing manufacturing environment has successfully been demonstrated. / Tiivistelmä Viime vuosikymmeninä asiakkaiden ostokäyttäytyminen on muuttunut merkittävästi. Ennen asiakkaiden hintatietoisuus johti yhtenäisiin tuotteisiin, kun taas nykyään vaaditaan moninaisempia tuotteita ja muokattavuutta kohtuulliseen hintaan. Samaan aikaan odotetaan korkealaatuisia tuotteita ja nopeaa toimitusta. Nämä seikat ovat aiheuttaneet tuotantoteollisuudelle uusia haasteita. Reagoidakseen nopeasti asiakkaiden vaatimuksiin tuotannonsuunnittelussa on alettu keskittymään korkealaatuisten tuotemuunnelmien määrän kasvattamiseen. Tämän vuoksi tarvitaan tuotantojärjestelmiä, jotka mahdollistavat nopean Ramp Up -prosessin, moneenmuuntuvan tuotannon ja nopean mukautuvuuden. Tätä aihetta on viime vuosina lähestytty esimerkiksi agentteihin perustuvien ja holonisten tuotantojärjestelmien kautta. Kuitenkin näihin tulevaisuuden haasteisiin pystytään vastaamaan vain kompleksisilla arkkitehtuureilla ja järjestelmän entiteeteille ominaisia ovat hyvin mukautuvat käyttäytymismallit. Näiden toteuttamiseen tarvitaan paljon työtä ja järjestelmillä on tapana käyttäytyä epä-deterministisesti. Lisäksi ylhäältä alas lähestymistapa johtaa usein tehtaan täydelliseen uudelleenorganisointiin, minkä vuoksi lähestymistapaa ei suosita oikeissa teollisuusympäristöissä. Tämän väitöstyön tarkoituksena on kehittää mukautuville tuotantojärjestelmille arkkitehtuuri, joka mahdollistaa järjestelmien helpon käyttöönoton teollisuudessa. Arkkitehtuuri perustuu alhaalta ylös -lähestymistapaan ja sisältää uudenlaisen joustavan ja älykkään tuotantotilakomponentin, manufactronin. Arkkitehtuuri kattaa kaikki perinteisen tehdasorganisaation kerrokset keskittyen kuitenkin erityisesti tuotantotilojen organisointiin. Lähestymistapa ja tulokset perustuvat Euroopan Unionin XPRESS-tutkimusprojektiin. Projektissa tehtiin yhteistyötä kolmen suuren teollisuushaaran kanssa tarkoituksena löytää joustava tuotantojärjestelmäratkaisu tulevaisuutta varten. Arkkitehtuuria sovellettiin XPRESS-projektissa lentokone-, auto- ja elektoniikkateollisuuteen ja testit osoittivat lähestymistavan soveltuvuuden. Myös lähestymistavan sujuva integrointi olemassa oleviin teollisuusjärjestelmiin osoitettiin onnistuneesti.

The main objective of the current study was to examine the trends and current status of lightweight design, optimization, and bionics in industrial applications. The goal wasto explore the suitable innovations used by industrial companies to ensure improved product performance and low costs of manufacturing. To achieve the goal, a secondary research methodology was employed in which seven studies on the topics of optimization, bionics, and lightweight designs were sampled and analyzed. A key resultnoted was that lightweight design is achieved through the use of magnesium alloys,aluminum alloys, and non-metallic materials such as carbon fiber-reinforced polymer.To optimize performance of the lightweight materials, computer technologies such as computer-assisted designs (CAD) are being used to ensure that the best shapes of the materials are utilized to offer the best performance. Meanwhile, bionics was employed by creating product designs which are inspired by nature such as meshless structures that minimize energy consumption, are cheaper, and are environmentally friendly.

This thesis summarizes the equations, algorithms and design decisions necessary for dynamic simulation of flexible bodies with moving contacts. The assumed general shape function approach is also presented. The approach is expected to be computationally less expensive than FEM approaches and easier to use than other reduction techniques. Additionally, the described technique enables studies of the residual stress release during grinding of flexible bodies. The overall software system design for a flexible multi-body simulation system BEAST is presented and the specifics of the flexible modeling is specially addressed. An industrial application example is also described in the thesis. The application presents some results from a case where the developed system is used for simulation of flexible ring grinding with material removal. / <p>Report code: LiU-TEK-LIC-2002:62.</p>

RANS models in CFD are used to predict the liner wall heat transfer characteristics of a gas turbine annular combustor with radial swirlers, over a Reynolds number range from 50,000 to 840,000. A three dimensional hybrid mesh of around twenty five million cells is created for a periodic section of an annular combustor with a single radial swirler. Different turbulence models are tested and it is found that the RNG k-e model with swirl correction gives the best comparisons with experiments. The Swirl number is shown to be an important factor in the behavior of the resulting flow field. The swirl flow entering the combustor expands and impinges on the combustor walls, resulting in a peak in heat transfer coefficient. The peak Nusselt number is found to be quite insensitive to the Reynolds number only increasing from 1850 at Re=50,000 to 2200 at Re=840,000, indicating a strong dependence on the Swirl number which remains constant at 0.8 on entry to the combustor. Thus the peak augmentation ratio calculated with respect to a turbulent pipe flow decreases with Reynolds number. As the Reynolds number increases from 50,000 to 840,000, not only does the peak augmentation ratio decrease but it also diffuses out, such that at Re=840,000, the augmentation profiles at the combustor walls are quite uniform once the swirl flow impinges on the walls. It is surmised with some evidence that as the Reynolds number increases, a high tangential velocity persists in the vicinity of the combustor walls downstream of impingement, maintaining a near constant value of the heat transfer coefficient. The computed and experimental heat transfer augmentation ratios at low Reynolds numbers are within 30-40% of each other. / Master of Science

Ο βασικός στόχος της συγκεκριμένης διατριβής ήταν να εξεταστεί η δυνατότητα της τεχνικής LIBS όσον σφορά την ταχεία ποιοτική και ποσοτική ανάλυση της μεταλλουργικής σκωρίας (σε στερεή και υγρή μορφή) σε εργαστηριακή και βιομηχανική κλίμακα. Η τεχνική εφαρμόστηκε αρχικά σε καθαρά μέταλλα και έπειτα σε πρότυπα δείγματα τα οποία περιείχαν τα αντίστοιχα στοιχεία σε μήτρα CaO. Μελετήθηκαν τα χαρακτηριστικά του πλάσματος που παράγεται από παλμούς διάρκειας των τάξεων nsec και psec. Η θερμοκρασία πλάσματος και η ηλεκτρονική πυκνότητα μειώνονται παρόμοια ενώ υπολογίστηκαν ελαφρώς υψηλότερες τιμές στην περίπτωση του ns λέιζερ. Οι καμπύλες βαθμονόμησης έδειξαν πως η ευαισθησία της μεθόδου παραμένει σχεδόν η ίδια ανεξαρτήτως της διάρκειας παλμού. Τα όρια ανίχνευσης κυμάνθηκαν στην τάξη μερικών μερών του εκατομμυρίου (ppm). Στη συνέχεια μελετήθηκαν οι δυνατότητες της τεχνικής για on-line ανάλυση της σκωρίας. Ο δυνατότητες της τεχνικής εξαρτώνται κυρίως από τον λόγο (κρατήρας λέιζερ, ΚΛ)/(μέγεθος σχηματιζόμενης φάσης, ΜΣΦ), οι επιφανειακές ανωμαλίες στην στερεοποιημένη σκωρία καθώς και από την κατανομή του κάθε στοιχείου στην μήτρα. Διαπιστώθηκε πως ο βαθμός ανομοιογένειας της σκωρίας δεν επιδρά σημαντικά στην ακρίβεια της μεθόδου όταν ο λόγος ΚΛ/ΜΣΦ είναι μεγάλος. Σημαντική παράμετρος αποτελεί το γεγονός εάν τα στοιχεία βρίσκονται κατανεμημένα στην μήτρα της σκωρίας ή σε κάποια κρυσταλλική φάση. Η επίδραση των επιφανειακών ανωμαλιών στην ακρίβεια της μεθόδου μειώθηκε με την θραύση και πελλετοποίηση της σκωρίας αλλά, κυρίως για τα στοιχεία τα οποία βρίσκονται κατανεμημένα στην μήτρα της σκωρίας, προτείνεται η αποφυγή της πελλετοποίησης για ανάλυση με χρήση της μεθόδου LIBS. Η ακρίβεια της τεχνικής εξαρτάται σε μεγάλο βαθμό από τα πρότυπα δείγματα που θα χρησιμοποιηθούν για την κατασκευή των καμπύλων βαθμονόμησης. Οι καμπύλες βαθμονόμησης της υγρής σκωρίας εμφάνισαν ικανοποιητική γραμμική εξάρτηση μεταξύ της έντασης των γραμμών εκπομπής των στοιχείων με τις αντίστοιχες συγκεντρώσεις ενώ παρατηρήθηκε μικρή αύξηση όσον αφορά τις τιμές των εντάσεων της υγρής σκωρίας σε σχέση με αυτές της στερεάς σκωρίας κάτω από τις ίδιες πειραματικές συνθήκες. Επίσης παρατηρήθηκε μεγαλύτερη διαπλάτυνση στις γραμμές κάποιων στοιχείων στην υγρή σκωρία. Για συγκεντρώσεις >4-5% παρατηρήθηκε επίσης αύξηση στην κλίση των καμπύλων για την περίπτωση της υγρής σκωρίας. Τέλος, κάθε στοιχείο συμπεριφέρεται διαφορετικά σε σχέση με τα υπόλοιπα, από δείγμα σε δείγμα αλλά και από φάση σε φάση. / To investigate the ability of LIBS technique considering the rapid qualitative and quantitative analysis of metallurgic slag was the main objective of the particular thesis. Firstly, the LIBS technique applied on pure metals and then on samples containing the same metals in CaO matrix and the time-resolved characteristics of the plasmas produced by nsec and psec pulses were studied. Both the plasma temperature and electron density are decaying similarly and the space-averaged values determined in the nanosecond case are slightly higher than for the picosecond one. Moreover, the calibration curves obtained, show that the inherent sensitivity of the technique remains almost unaltered independently of the pulse duration. The detection limits were found to be few ppm. Then, the potentiality of LIBS method for quantitative on-line, multi-element slag analysis on plant scale was examined. Further, in order to examine more closely the produced slag, slag samples were analysed in the laboratory. The measurements were performed on solidified slag samples in a pelletized form and on as delivered solidified slag samples. The limits of the accuracy of this technique depend mainly on the laser spot/phase size ratio, the level of surface abnormalities and the distribution of each element in the matrix. The non-homogeneity level of the slag product seems to be not important in LIBS analysis, when the above ratio is quite large. It is of great importance whether the element is embedded in the matrix or in a specific crystallized phase. The influence of surface abnormalities is reduced in the case of pressed slag, but primarily for the elements distributed in the matrix, fragmentation of the slag should be avoided. The accuracy of LIBS quantitative slag analysis is strongly dependent on the standard samples that are used Regarding the liquid slag analysis, the calibration curves presented satisfactory linear dependence between the intensity of analytic lines with the corresponding concentrations while the intensity values of liquid slag appeared to be relatively increased with regard to the intensity values of solid slag under the same experimental conditions. Widening phenomena were characterized the lines of certain elements in liquid slag. For concentrations >4-5% an increased slope in calibration curves of liquid slag was observed. Finally, it was observed that each element behaves in a different way from sample in sample but also from phase in phase.