906 resultados para closed-loop supply chains


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The development of bioenergy on the basis of wood fuels has received considerable attention in the last decades. The combination of large forest resources and reliance on fossil fuels makes the issue of wood chips usage in Russia an actual topic for the analysis. The main objective of this study is to disclose the current state and perspectives for the production of wood chips and their usage as a source of energy in the North-West of Russia. The study utilizes an integrated approach to explore the market of wood chips on the basis of comprehensive analysis of documentation and expert opinions. The analysis of wood chips market was performed for eight regions of the North-West district of Russia within two major dimensions: its current state and perspectives in the nearest five years. The results of the study show a comprehensive picture of the wood chips market, including the potential for wood chips production, the specific features of production and consumption and the perspectives for the market development within the regions of the North-West district of Russia. The study demonstrated that the market of wood chips is underdeveloped in the North-West of Russia. The findings of the work may be used by forest companies for the strategic planning.

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The objective of this study was to model mathematically and to simulate the dynamic behavior of an auger-type fertilizer applicator (AFA) in order to use the variable-rate application (VRA) and reduce the coefficient of variation (CV) of the application, proposing an angular speed controller θ' for the motor drive shaft. The input model was θ' and the response was the fertilizer mass flow, due to the construction, density of fertilizer, fill factor and the end position of the auger. The model was used to simulate a control system in open loop, with an electric drive for AFA using an armature voltage (V A) controller. By introducing a sinusoidal excitation signal in V A with amplitude and delay phase optimized and varying θ' during an operation cycle, it is obtained a reduction of 29.8% in the CV (constant V A) to 11.4%. The development of the mathematical model was a first step towards the introduction of electric drive systems and closed loop control for the implementation of AFA with low CV in VRA.

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The present study shows the development, simulation and actual implementation of a closed-loop controller based on fuzzy logic that is able to regulate and standardize the mass flow of a helical fertilizer applicator. The control algorithm was developed using MATLAB's Fuzzy Logic Toolbox. Both open and closed-loop simulations of the controller were performed in MATLAB's Simulink environment. The instantaneous deviation of the mass flow from the set point (SP), its derivative, the equipment´s translation velocity and acceleration were all used as input signals for the controller, whereas the voltage of the applicator's DC electric motor (DCEM) was driven by the controller as output signal. Calibration and validation of the rules and membership functions of the fuzzy logic were accomplished in the computer simulation phase, taking into account the system's response to SP changes. The mass flow variation coefficient, measured in experimental tests, ranged from 6.32 to 13.18%. The steady state error fell between -0.72 and 0.13g s-1 and the recorded average rise time of the system was 0.38 s. The implemented controller was able to both damp the oscillations in mass flow that are characteristic of helical fertilizer applicators, and to effectively respond to SP variations.

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Kohdeorganisaatiossa on havaittu tarvetta kustannusten tarkemmalle ennustamiselle liiketoimintaympäristön ja palvelutarjooman muutosten seurauksena. Diplomityön päätavoitteena on selvittää, kuinka palvelualan yritykselle rakennetaan toimintopohjainen kustannusten ennustemalli. Päätavoitetta lähestytään selvittämällä mallin rakennusvaiheet, soveltuvuus kohdeorganisaatiolle ja siitä saatava lisäarvo. Tutkielmassa käytetään konstruktiivista tutkimusotetta. Malli pohjautuu toimintopohjaisen suunnittelun ja budjetoinnin suljetun silmukkamallin teoriaan. Empiriaosassa suoritetaan mallin rakentaminen vaiheittain. Työn tulokset osoittavat toimintopohjaisen suunnittelun ja budjetoinnin suljetun silmukkamallin soveltuvuuden kohdeorganisaation toimintojen mallinnukseen. Toimintopohjaisesta ennustemallista on saatavissa lisäarvoa budjetointiin ja skenaariotyöhön. Mallin avulla voidaan tarkastella budjetoinnin realistisuutta. Skenaariotyöstä voidaan saada tukea päätöksentekoon, koska erilaisten toimenpiteiden vaikutuksia voidaan arvioida resurssitarpeen ja kustannusten näkökulmasta.

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Combating climate change is one of the key tasks of humanity in the 21st century. One of the leading causes is carbon dioxide emissions due to usage of fossil fuels. Renewable energy sources should be used instead of relying on oil, gas, and coal. In Finland a significant amount of energy is produced using wood. The usage of wood chips is expected to increase in the future significantly, over 60 %. The aim of this research is to improve understanding over the costs of wood chip supply chains. This is conducted by utilizing simulation as the main research method. The simulation model utilizes both agent-based modelling and discrete event simulation to imitate the wood chip supply chain. This thesis concentrates on the usage of simulation based decision support systems in strategic decision-making. The simulation model is part of a decision support system, which connects the simulation model to databases but also provides a graphical user interface for the decisionmaker. The main analysis conducted with the decision support system concentrates on comparing a traditional supply chain to a supply chain utilizing specialized containers. According to the analysis, the container supply chain is able to have smaller costs than the traditional supply chain. Also, a container supply chain can be more easily scaled up due to faster emptying operations. Initially the container operations would only supply part of the fuel needs of a power plant and it would complement the current supply chain. The model can be expanded to include intermodal supply chains as due to increased demand in the future there is not enough wood chips located close to current and future power plants.

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The objective of this master thesis is to test according to hoisting requirements, a servo drive system and compare its performance with the performance of a drive equipped with a vector controlled frequency converter. Both systems utilize closed-loop vector control based on PCL program control. In order to compare the results of tests both systems were connected to the same motor driving a variable speed electrical chain hoist. Tests were based on requirements to both systems. As requirements of tests zero speed operation, operation in field weakening, positioning accuracy and smoothness of motion are taken into consideration. Both systems demonstrate quite similar performance and meet the requirements. Servo drive system demonstrates a high positioning accuracy and dynamic performance. Frequency converter is not able to provide the same positioning accuracy and dynamic performance as servo drive.

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The management of port-related supply chains is challenging due to the complex and heterogeneous operations of the ports with several actors and processes. That is why the importance of information sharing is emphasised in the ports. However, the information exchange between different port-related actors is often cumbersome and it still involves a lot of manual work and paper. Major ports and port-related actors usually have advanced information systems in daily use but these systems are seldom interoperable with each other, which prevents economies of scale to be reached. Smaller ports and companies might not be equipped with electronic data transmission at all. This is the final report of the Mobile port (MOPO) project, which has sought ways to improve the management and control of port-related sea and inland traffic with the aid of ICT technologies. The project has studied port community systems (PCS) used worldwide, evaluated the suitability of a PCS for the Finnish port operating environment and created a pilot solution of a Finnish PCS in the port of HaminaKotka. Further, the dry port concept and its influences on the transportation system have been explored. The Mobile Port project comprised of several literature reviews, interviews of over 50 port-related logistics and/or ICT professionals, two different kinds of simulation models as well as designing and implementing of the pilot solution of the Finnish PCS. The results of these multiple studies are summarised in this report. Furthermore, recommendations for future actions and the topics for further studies are addressed in the report. The study revealed that the information sharing in a typical Finnish port-related supply chain contains several bottlenecks that cause delays in shipments and waste resources. The study showed that many of these bottlenecks could be solved by building a port community system for the Finnish port community. Almost 30 different kinds of potential services or service entities of a Finnish PCS were found out during the study. The basic requirements, structure, interfaces and operation model of the Finnish PCS were also defined in the study. On the basis of the results of the study, a pilot solution of the Finnish PCS was implemented in the port of HaminaKotka. The pilot solution includes a Portconnect portal for the Finnish port community system (available at https://www.portconnect.fi) and two pilot applications, which are a service for handling the information flows concerning the movements of railway wagons and a service for handling the information flows between Finnish ports and Finland-Russian border. The study also showed that port community systems can be used to improve the environmental aspects of logistics in two different ways: 1) PCSs can bring direct environmental benefits and 2) PCSs can be used as an environmental tool in a port community. On the basis of the study, the development of the Finnish port community system should be continued by surveying other potential applications for the Finnish PCS. It is also important to study if there is need and resources to extend the Finnish PCS to operate in several ports or even on a national level. In the long run, it could be reasonable to clarify whether there would be possibilities to connect the Finnish PCS as a part of Baltic Sea wide, European-wide or even worldwide maritime and port-related network in order to get the best benefit from the system

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Sequestration of carbon dioxide in mineral rocks, also known as CO2 Capture and Mineralization (CCM), is considered to have a huge potential in stabilizing anthropogenic CO2 emissions. One of the CCM routes is the ex situ indirect gas/sold carbonation of reactive materials, such as Mg(OH)2, produced from abundantly available Mg-silicate rocks. The gas/solid carbonation method is intensively researched at Åbo Akademi University (ÅAU ), Finland because it is energetically attractive and utilizes the exothermic chemistry of Mg(OH)2 carbonation. In this thesis, a method for producing Mg(OH)2 from Mg-silicate rocks for CCM was investigated, and the process efficiency, energy and environmental impact assessed. The Mg(OH)2 process studied here was first proposed in 2008 in a Master’s Thesis by the author. At that time the process was applied to only one Mg-silicate rock (Finnish serpentinite from the Hitura nickel mine site of Finn Nickel) and the optimum process conversions, energy and environmental performance were not known. Producing Mg(OH)2 from Mg-silicate rocks involves a two-staged process of Mg extraction and Mg(OH)2 precipitation. The first stage extracts Mg and other cations by reacting pulverized serpentinite or olivine rocks with ammonium sulfate (AS) salt at 400 - 550 oC (preferably < 450 oC). In the second stage, ammonia solution reacts with the cations (extracted from the first stage after they are leached in water) to form mainly FeOOH, high purity Mg(OH)2 and aqueous (dissolved) AS. The Mg(OH)2 process described here is closed loop in nature; gaseous ammonia and water vapour are produced from the extraction stage, recovered and used as reagent for the precipitation stage. The AS reagent is thereafter recovered after the precipitation stage. The Mg extraction stage, being the conversion-determining and the most energy-intensive step of the entire CCM process chain, received a prominent attention in this study. The extraction behavior and reactivity of different rocks types (serpentinite and olivine rocks) from different locations worldwide (Australia, Finland, Lithuania, Norway and Portugal) was tested. Also, parametric evaluation was carried out to determine the optimal reaction temperature, time and chemical reagent (AS). Effects of reactor types and configuration, mixing and scale-up possibilities were also studied. The Mg(OH)2 produced can be used to convert CO2 to thermodynamically stable and environmentally benign magnesium carbonate. Therefore, the process energy and life cycle environmental performance of the ÅAU CCM technique that first produces Mg(OH)2 and the carbonates in a pressurized fluidized bed (FB) were assessed. The life cycle energy and environmental assessment approach applied in this thesis is motivated by the fact that the CCM technology should in itself offer a solution to what is both an energy and environmental problem. Results obtained in this study show that different Mg-silicate rocks react differently; olivine rocks being far less reactive than serpentinite rocks. In summary, the reactivity of Mg-silicate rocks is a function of both the chemical and physical properties of rocks. Reaction temperature and time remain important parameters to consider in process design and operation. Heat transfer properties of the reactor determine the temperature at which maximum Mg extraction is obtained. Also, an increase in reaction temperature leads to an increase in the extent of extraction, reaching a maximum yield at different temperatures depending on the reaction time. Process energy requirement for producing Mg(OH)2 from a hypothetical case of an iron-free serpentine rock is 3.62 GJ/t-CO2. This value can increase by 16 - 68% depending on the type of iron compound (FeO, Fe2O3 or Fe3O4) in the mineral. This suggests that the benefit from the potential use of FeOOH as an iron ore feedstock in iron and steelmaking should be determined by considering the energy, cost and emissions associated with the FeOOH by-product. AS recovery through crystallization is the second most energy intensive unit operation after the extraction reaction. However, the choice of mechanical vapor recompression (MVR) over the “simple evaporation” crystallization method has a potential energy savings of 15.2 GJ/t-CO2 (84 % savings). Integrating the Mg(OH)2 production method and the gas/solid carbonation process could provide up to an 25% energy offset to the CCM process energy requirements. Life cycle inventory assessment (LCIA) results show that for every ton of CO2 mineralized, the ÅAU CCM process avoids 430 - 480 kg CO2. The Mg(OH)2 process studied in this thesis has many promising features. Even at the current high energy and environmental burden, producing Mg(OH)2 from Mg-silicates can play a significant role in advancing CCM processes. However, dedicated future research and development (R&D) have potential to significantly improve the Mg(OH)2 process performance.

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The birth of Internet technologies, the developments of fast fashion and multiple retailing channels have created a need for a new, more integrated way for doing retailing. Agility in fast fashion retailing could be seen as a significant way of responding to these changes and furthermore, as a way to respond to consumers’ altering demands. The purpose of this study was to explore the ways in which agile supply chains and integrated multichannel retailing influence the international fast fashion retailing. A framework for agility in retail was developed based on available theoretical considerations in distribution and communication channels. Qualitative research methods and qualitative content analysis were used. Four expert interviews were carried out to gain new perspectives to the objectives. The rest of the data was collected from an industry specific document, expert video and two expert lectures. Following the data collection, the research material was analyzed with qualitative content analysis. The empirical findings on agility in retail were presented based on a coding frame. It was found that agility in retail has multiple parts, which are overlapping and affecting one another. Furthermore, instead of viewing the agile supply chain and integrated multichannel retailing separately of each other as usual, it was found that they should be integrated, and the term “agility” was proposed to denote this approach. Also, it was found that the most common drivers and constrains of integrated multichannel retailing were the new Internet technologies and customer demand. Brick-and-mortar store, online store, mobile devices and social media were found to be the most common retailing channels. Furthermore, in-store technology, click-and-collect approach, NFC-buying, RFID-technology as well as 3D- digital simulations on fabrics and patterns will enhance agility even more in the future. In addition, environmental issues, customer experiences and communication will be important factors. This study has provided new practical insights for the future retailing. Furthermore, it has contributed to the academic research by discussing the traditional approaches of agility in fast fashion retail and bringing in new insights.

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The importance of efficient supply chain management has increased due to globalization and the blurring of organizational boundaries. Various supply chain management technologies have been identified to drive organizational profitability and financial performance. Organizations have historically been concentrating heavily on the flow of goods and services, while less attention has been dedicated to the flow of money. While supply chains are becoming more transparent and automated, new opportunities for financial supply chain management have emerged through information technology solutions and comprehensive financial supply chain management strategies. This research concentrates on the end part of the purchasing process which is the handling of invoices. Efficient invoice processing can have an impact on organizations working capital management and thus provide companies with better readiness to face the challenges related to cash management. Leveraging a process mining solution the aim of this research was to examine the automated invoice handling process of four different organizations. The invoice data was collected from each organizations invoice processing system. The sample included all the invoices organizations had processed during the year 2012. The main objective was to find out whether e-invoices are faster to process in an automated invoice processing solution than scanned invoices (post entry into invoice processing solution). Other objectives included looking into the longest lead times between process steps and the impact of manual process steps on cycle time. Processing of invoices from maverick purchases was also examined. Based on the results of the research and previous literature on the subject, suggestions for improving the process were proposed. The results of the research indicate that scanned invoices were processed faster than e-invoices. This is mostly due to the more complex processing of e-invoices. It should be noted however that the manual tasks related to turning a paper invoice into electronic format through scanning are ignored in this research. The transitions with the longest lead times in the invoice handling process included both pre-automated steps as well as manual steps performed by humans. When the most common manual steps were examined in more detail, it was clear that these steps had a prolonging impact on the process. Regarding invoices from maverick purchases the evidence shows that these invoices were slower to process than invoices from purchases conducted through e-procurement systems and from preferred suppliers. Suggestions on how to improve the process included: increasing invoice matching, reducing of manual steps and leveraging of different value added services such as invoice validation service, mobile solutions and supply chain financing services. For companies that have already reaped all the process efficiencies the next step is to engage in collaborative financial supply chain management strategies that can benefit the whole supply chain.

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Tässä työssä luodaan diagnostiikkatyökalu toimitusketjun nykytilan määritystä varten. Sen tavoitteena on muodostaa tieteellisen kirjallisuuden pohjalta selkeästi esitettävissä oleva prosessimuotoinen työkalu, jota voidaan käyttää mahdollisimman monessa erilaisessa toimitusketjussa. Lisäksi sen tulee olla sopiva yrityksen ulkopuolisen toimijan, esimerkiksi konsultin, käytettäväksi. Työssä käydään ensin läpi toimitusketjun diagnosoinnin ja sen suorituskyvyn mittauksen teoriaa. Sen jälkeen muodostetaan näiden avulla tavoitteita vastaava nelivaiheinen työkalu, joka ulottuu aina projektin suunnittelusta mittaukseen, kehitystoimenpiteiden tunnistamiseen ja niiden esittämiseen yrityksen johdolle.

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The goal of the Master’s thesis is to design a test stand for a centrifugal compressor. Different theoretical aspects of flow parameters measurements and test rigs built for the similar purposes in other research units are described in the theoretical part of the work. The process of components selection and the description of chosen components are given in the second part of the thesis. Besides measuring and control stages, the designed test stand has a closed-loop piping, an aftercooler and a surge tank. Overview and layout of the test rig is presented in the last chapter of the work.

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Kysynnän ja tarjonnan epävarmuudet ovat nykyisin arkipäivää useilla toimialoilla. Elämme epävarmuuden suhteen ennen näkemättömiä aikoja, minkä on arvioitu jatkuvan myös tulevaisuudessa. Yritysten tilauskannat ovat lyhyitä, ja tilaukset viivästyvät tai peruuntuvat kokonaan. Toisaalta tarjonnan epävarmuudet aiheuttavat asiakasyrityksille haasteita esimerkiksi toimitusmyöhästymisten muodossa. Tuotannon ollessa hajaantunut verkostoihin yksittäisten yritysten toiminta ja päätökset vaikuttavat toisten verkostoyritysten toimintaan. Tämän takia epävarmuuden aiheuttamista muutoksista ja poikkeamista tulisi tiedottaa kumppaniyrityksiä, jotta kaikki pysyisivät samalla kellotaajuudella. Operatiivisen ja taktisen tiedon jakaminen on nykyisissä toimitusketjuissa jo arkipäivää, mutta yritysten välisistä rajapinnoista löytyy edelleen kehitettävää. Riittävästä ei kiinnitetä huomiota vastaanottajan kykyyn ja tapaan hyödyntää informaatiota – varsinkaan muutostilanteissa. Ajan/nopeuden ollessa yhä tärkeämpi kilpailutekijä informaation ajoituksella on kriittinen merkitys kysyntä-toimitusketjujen kokonaissuorituskykyyn. Toisin sanoen, millä ajanhetkellä tietoa tulisi jakaa, jotta kumppani pystyisi hyödyntämään saamaansa tietoa mahdollisimman hyvin. Kysyntä-toimitusketjun synkronoinnilla tarkoitetaan tässä väitöstutkimuksessa nimenomaan aikatekijään keskittymistä yritysten välisessä päätöksenteossa ja informaation jakamisessa toimitusketjun kokonaissuorituskyvyn parantamiseksi. Tutkimus kytkeytyy toimitusketjukoordinoinnin tieteelliseen keskusteluun. Koordinointiteorian keskeinen osa ovat riippuvuussuhteet, joita johdetaan koordinointimekanismien avulla. Kysyntätoimitusketjun synkronointia on mallinnettu aikaisemmin VOP-OPP-mallin (Value Offering Point – Order Penetration Point) ja sen johdannaisten avulla. Näissä malleissa asiakasyrityksen kysyntäketju ja toimittajayrityksen toimitusketju ovat keskinäisessä riippuvuussuhteessa, jota johdetaan päätöksenteon synkronoinnin ja informaation jakamisen koordinointimekanismeilla. VOP-OPP-malli johdannaisineen eivät kuitenkaan huomioi epävarman toimintaympäristön vaikutuksia synkronointiin. Näissä malleissa informaation ainoana laatudimensiona tarkasteltava aikatekijä on liian kapea-alainen näkökulma synkronointiin epävarmassa ympäristössä. Lisäksi nämä mallit keskittyvät vain yksisuuntaiseen, kysyntälähtöiseen, synkronointiin jättäen huomioimatta tarjontalähtöisen synkronoinnin. Aikatekijä- ja kokonaissuorituskykypainotustensa takia VOP-OPP-malli tarjosi kuitenkin hyvän lähtöfilosofian uusien synkronointimallien kehittämiseen. Väitöstutkimus toteutettiin hypoteettis-deduktiivisena tapaustutkimuksena, jossa ensin luotiin kirjallisuuden perusteella uudet teoreettiset synkronointimalliehdotukset. Tämän jälkeen ehdotusten toimivuutta arvioitiin käytännön kysyntä-toimitusketjuissa. Tutkimuksen uutuusarvo liittyy kysyntä-toimitusketjun synkronoinnin keskeisten piirteiden systeemiseen mallintamiseen epävarmassa toimintaympäristössä. Kontribuutiona esitetään kysyntä-toimitusketjun synkronoinnin moniulotteinen kokonaismalli, joka sisältää koordinointimekanismeina päätöksenteon synkronoinnin, informaation läpinäkyvyyden sekä asiakas- ja toimittajapään joustot. Tiedon vaihtoa mallissa tarkastellaan kaksisuuntaisesti – kysyntä- ja tarjontalähtöisesti. Informaation laatudimensioina mallissa ovat informaation ajoitus, luotettavuus ja tarkkuus. Kokonaismalli sisältää kolme alimallia: Demand Visibility Point – Demand Penetration Point (DVP-DPP) on kysyntälähtöisen synkronoinnin malli, Supply Visibility Point – Supply Information Penetration Point (SVP-SIPP) on tarjontalähtöisen synkronoinnin malli ja Integroitu DVP-DPP - SVP-SIPP-malli kytkee edellä mainitut mallit toisiinsa. Näissä alimalleissa informaation eri luokkia ovat tilausta edeltävä, tilaukseen liittyvä, tilauksen jälkeinen ja sovitun toimitusajankohdan jälkeinen kysyntä- ja tarjontatieto. Käytännön hyödyntämisen näkökulmasta mallit toimivat ns. mentaalitason koordinointimekanismeina, joiden tarkoitus on herättää toimitusketjukumppanit tavoittelemaan kokonaissuorituskyvyn parantamista oman edun tavoittelemisen sijasta. Tutkimuksen päärajoitteena on sen keskittyminen ainoastaan kahdenvälisiin yhteistyösuhteisiin, mikä tarjoaa nykyisessä verkostoituneessa toimintaympäristössä varsin kapean kuvan käytännön synkronointihaasteisiin.

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The assembly and maintenance of the International Thermonuclear Experimental Reactor (ITER) vacuum vessel (VV) is highly challenging since the tasks performed by the robot involve welding, material handling, and machine cutting from inside the VV. The VV is made of stainless steel, which has poor machinability and tends to work harden very rapidly, and all the machining operations need to be carried out from inside of the ITER VV. A general industrial robot cannot be used due to its poor stiffness in the heavy duty machining process, and this will cause many problems, such as poor surface quality, tool damage, low accuracy. Therefore, one of the most suitable options should be a light weight mobile robot which is able to move around inside of the VV and perform different machining tasks by replacing different cutting tools. Reducing the mass of the robot manipulators offers many advantages: reduced material costs, reduced power consumption, the possibility of using smaller actuators, and a higher payload-to-robot weight ratio. Offsetting these advantages, the lighter weight robot is more flexible, which makes it more difficult to control. To achieve good machining surface quality, the tracking of the end effector must be accurate, and an accurate model for a more flexible robot must be constructed. This thesis studies the dynamics and control of a 10 degree-of-freedom (DOF) redundant hybrid robot (4-DOF serial mechanism and 6-DOF 6-UPS hexapod parallel mechanisms) hydraulically driven with flexible rods under the influence of machining forces. Firstly, the flexibility of the bodies is described using the floating frame of reference method (FFRF). A finite element model (FEM) provided the Craig-Bampton (CB) modes needed for the FFRF. A dynamic model of the system of six closed loop mechanisms was assembled using the constrained Lagrange equations and the Lagrange multiplier method. Subsequently, the reaction forces between the parallel and serial parts were used to study the dynamics of the serial robot. A PID control based on position predictions was implemented independently to control the hydraulic cylinders of the robot. Secondly, in machining, to achieve greater end effector trajectory tracking accuracy for surface quality, a robust control of the actuators for the flexible link has to be deduced. This thesis investigates the intelligent control of a hydraulically driven parallel robot part based on the dynamic model and two schemes of intelligent control for a hydraulically driven parallel mechanism based on the dynamic model: (1) a fuzzy-PID self-tuning controller composed of the conventional PID control and with fuzzy logic, and (2) adaptive neuro-fuzzy inference system-PID (ANFIS-PID) self-tuning of the gains of the PID controller, which are implemented independently to control each hydraulic cylinder of the parallel mechanism based on rod length predictions. The serial component of the hybrid robot can be analyzed using the equilibrium of reaction forces at the universal joint connections of the hexa-element. To achieve precise positional control of the end effector for maximum precision machining, the hydraulic cylinder should be controlled to hold the hexa-element. Thirdly, a finite element approach of multibody systems using the Special Euclidean group SE(3) framework is presented for a parallel mechanism with flexible piston rods under the influence of machining forces. The flexibility of the bodies is described using the nonlinear interpolation method with an exponential map. The equations of motion take the form of a differential algebraic equation on a Lie group, which is solved using a Lie group time integration scheme. The method relies on the local description of motions, so that it provides a singularity-free formulation, and no parameterization of the nodal variables needs to be introduced. The flexible slider constraint is formulated using a Lie group and used for modeling a flexible rod sliding inside a cylinder. The dynamic model of the system of six closed loop mechanisms was assembled using Hamilton’s principle and the Lagrange multiplier method. A linearized hydraulic control system based on rod length predictions was implemented independently to control the hydraulic cylinders. Consequently, the results of the simulations demonstrating the behavior of the robot machine are presented for each case study. In conclusion, this thesis studies the dynamic analysis of a special hybrid (serialparallel) robot for the above-mentioned special task involving the ITER and investigates different control algorithms that can significantly improve machining performance. These analyses and results provide valuable insight into the design and control of the parallel robot with flexible rods.

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The aim of the present thesis was to explore possible promotional actions to support the emergence of eco-industrial business networks in Finland. The main objectives were to investigate what kind of factors affect in the development of eco-industrial networks and further make suggestions in what kinds of actions this could be supported. In addition, since the active facilitation was discovered as one potential promoting activity, further investigation about facilitation process in Finnish context was conducted and also main characteristics of nationwide facilitation programme were identified. This thesis contains literature review of network orchestration and eco-industrial networks. The latter consists of green supply chain management and industrial symbiosis, although the main focus of the study leans on the concept of industrial symbiosis. The empirical data of the study was obtained from semi-structured expert interviews. These interviews were analyzed using qualitative content analysis. The study identified four main promotional activities for eco-industrial networks: 1) building awareness, 2) incentives, 3) dismantling of legislative barriers and 4) active facilitation. In addition, a framework for facilitation activities in Finnish context was built and main characteristics of nationwide facilitation programme were identified.