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)

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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>

<p>The industrial application of production planning and process scheduling optimization is addressed in this thesis. The first part of the thesis addresses the research into process scheduling application. Several scheduling models are developed based on both discrete and continuous time modelling frameworks. Extensions to both frameworks are presented to address unique production policies and maintenance activities. The potential benefits of schedule optimization is determined through several comparative industrial case studies. The weekly production schedules of the actual plant are compared against the schedules generated by optimization. The historical plant performance is ascertained and areas where efficiency gains are possible are highlighted. In addition, the scheduling model is used to investigate potential changes to production policies.</p> <p>The second part of the thesis addresses the research conducted in production planning application. The main goal of production planning is the efficient generation of a plan that specifies production targets for products over a medium term horizon. Direct application of previously proposed planning models fails to model several unique and key processing features of the production facility. A production planning model is presented that relaxes the detailed scheduling model structure and exploits the use of traveling salesman type constraints to accurately model sequence dependent changeovers. Two case studies are presented to investigate the benefits of optimization in production planning. The first case study investigates the lowest cost planning solution over a three month planning horizon. The second case study investigates the effects of a key production parameter on the optimality of solution. The results highlight the potential benefit of optimization application in increasing plant processing efficiency and reducing unnecessary production downtime.</p> <p>Finally, a modelling framework is presented that allows for the combined scheduling of production and maintenance. The framework allows for maintenance with various timing requirements and extends the capabilities of current frameworks.</p> / Master of Applied Science (MASc)

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