122 resultados para Hybrid working machines


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Melu on epämiellyttävää ja tarpeetonta ääntä. Se saattaa olla myös fysiologisesti haitallista aiheuttaen pahimmassa tapauksessa pysyvän kuulovaurion. Tämän diplomityön tavoitteena oli saada vähennettyä työntekijöiden päivittäistä meluannosta alle 80 desibeliin, jotta työntekijöiden työturvallisuus ja työskentelyolosuhteet paranisivat. Työn teoriaosuudessa kerrotaan yleisiä asioita äänestä, sen mittaamisesta, vaikutuksista ihmisiin, laitevalmistajien ja työnantajien velvollisuuksia sekä meluntorjunnan perusteita. Käytännön osiossa käydään läpi aikaisemmin tehtyjen melumittausten tuloksia, esitellään mittauksissa käytettyjä laitteita, esitellään kohteet joihin parannuksia tehtiin ja miten ne tehtiin, sekä käydään läpi kuinka suuri vaikutus kullakin parannuksella on ollut. Lisäksi verrataan ennen parannuksia tehtyjen meluannosmittausten tuloksia parannusten jälkeisiin tuloksiin. Tulokset olivat hyviä, sillä täyttökoneilla työskentelevien työntekijöiden meluannosmäärät putosivat alle 80 desibeliin.

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Tämä työ on tehty Stora Enson Imatran kartonkitehtaan kunnossapidosta vastaavalle Efora Oy:lle. Tavoitteena oli selvittää syy Imatran Kartonkikone 5:n kuivatussylinterien laakerivaurioiden suureen määrään verrattuna tehtaiden kolmeen muuhun kartonkikoneeseen. Tutkimuksissa keskityttiin laakerien käyttöolosuhteisiin. Syyn selvittämiseksi työssä vertailtiin eri kartonkikoneiden kiertoöljyvoitelujärjestelmiä, voiteluöljyjä, voiteluolosuhteita, öljyjen kuntoa ja kunnon seurantaa. Myös laakereihin kohdistuvia kuormia arvioitiin. Alan kirjallisuuden avulla on käyty läpi kartonkikoneen rakennetta ja toimintaa tarvittavassa laajuudessa, voitelun ja laakerin vaurioitumisen teoriaa sekä voiteluaineiden ominaisuuksien ja koostumuksen perusteita. Vertailevissa tutkimuksissa ei löytynyt vauriomäärien eroja selittäviä eroavaisuuksia Imatran tehtaiden eri kartonkikoneiden välillä, joskin Kartonkikone 5:n kiertovoiteluöljyn puhtaustaso oli muita Imatran kartonkikoneita heikompi. Laakerikuormien osalta havaittiin joidenkin laakerien käyvän laakerille asetetun vähimmäiskuorman alittavilla kuormituksilla. Vähimmäiskuormaa pienempi radiaalikuorma voi johtaa laakerin virheelliseen toimintaan ja edelleen vaurioitumiseen. Voiteluolosuhteet todettiin erittäin vaikeiksi ja niillä on epäilemättä vaikutusta voiteluöljyn ja laakerien lyhentyneeseen käyttöikään.

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Working capital is an investment which is tied up into the inventories and accounts receivable and which is released with accounts payable. Due to the current business landscape with tightened financial conditions and finance markets, organizations emphasize efficient working capital management. With efficient working capital management, a company can reduce the need of finance, free up cash, increase profitability, improve liquidity, increase the efficiency of operations, and decrease (financing) costs. From the perspective of an individual company, efficient working capital management means decreasing inventory levels by shortening the cycle time of inventories, decreasing accounts receivable by shortening the trade credit terms and effective collection procedures, and increasing the level of accounts payable by paying the suppliers later. From an inter-organizational perspective, however, working capital should not be sub-optimized by a single company but holistic view to working capital management through the supply chain should be adopted to create value and improve performance together. The purpose of this research is to take academic research as well as practical management towards inter-organizational working capital management. The thesis discusses the benefits as well as mechanisms of working capital management in the inter-organizational context and has two main objectives: (1) to examine the effect of inter-organizational working capital management on performance in the value chain context and (2) to develop models of working capital management for internal as well as inter-organizational value chains. The results of the archival research conducted in the value chain of the pulp and paper industry and the value chain of the automotive industry indicate that companies can increase relative profitability by managing working capital comprehensively by taking into account all three components, and holistically though the value chain. Companies in the value chain benefit from different strategies in working capital management depending on the position of the company in the value chain. This can be taken into account in inter-organizational working capital management. The effects of inter-organizational working capital management actions on the financing costs of working capital were studied via simulations. Simulations also show that the value chain and individual companies benefit from an inter-organizational view to working capital management. Inter-organizational working capital management actions include for example: shortening the cycle time of inventories, reducing product costs, shifting inventories, shortening payment terms, and considering the cost of capital. The thesis also provides solutions for the practical requirements for tools to control working capital. The design science part of the research introduces the adjusted cash conversion cycle (ACCC) model for internal value chains, as well as models for working capital management in the inter-organizational value chain context: the working capital management model (WCMM) and the financial cycle time model (FCTM) designed in corporation and product levels respectively. This research contributes to literature on working capital management and interorganizational accounting. The research gives a holistic, inter-organizational view to the management of working capital. It advances the knowledge in working capital management on operational level, increases knowledge in the recently risen theme of supply chainoriented, collaborative working capital management, combines management accounting research with supply chain management research, and contributes to the demand of practical inter-organizational accounting methods. In addition, the research has strong practical focus as new managerial methods are introduced.

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When modeling machines in their natural working environment collisions become a very important feature in terms of simulation accuracy. By expanding the simulation to include the operation environment, the need for a general collision model that is able to handle a wide variety of cases has become central in the development of simulation environments. With the addition of the operating environment the challenges for the collision modeling method also change. More simultaneous contacts with more objects occur in more complicated situations. This means that the real-time requirement becomes more difficult to meet. Common problems in current collision modeling methods include for example dependency on the geometry shape or mesh density, calculation need increasing exponentially in respect to the number of contacts, the lack of a proper friction model and failures due to certain configurations like closed kinematic loops. All these problems mean that the current modeling methods will fail in certain situations. A method that would not fail in any situation is not very realistic but improvements can be made over the current methods.

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The objective of this thesis was to examine the potential of multi-axis solutions in packaging machines produced in Europe. The definition of a multi-axis solution in this study is a construction that uses a common DC bus power supply for different amplifiers running the axes and the intelligence is centralized into one unit. The cost structure of a packaging machine was gained from an automation research, which divided the machines according to automation categories. The automation categories were then further divided into different sub-components by evaluating the ratio of multi-axis solutions compared to other automation components in packaging machines. A global motion control study was used for further information. With the help of the ratio, an estimation of the potential of multi-axis solutions in each country and packaging machine sector was completed. In addition to the research, a specific questionnaire was sent to five companies to gain information about the present situation and possible trends in packaging machinery. The greatest potential markets are in Germany and Italy, which are also the largest producers of packaging machinery in Europe. The greatest growth in the next few years will be seen in Turkey where the annual growth rate equals the general machinery production rate in Asia. The greatest market potential of the Nordic countries is found in Sweden in 35th position on the list. According to the interviews, motion control products in packaging machines will retain their current power levels, as well as the number of axes in the future. Integrated machine safety features together with a universal programming language are the desired attributes of the future. Unlike generally in industry, the energy saving objectives are and will remain insignificant in the packaging industry.

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Joining processes and techniques need to meet the trend of new applications and the development of new materials. The application in connection with thick and thin plates in industrial fields is wide and the joining technology is in very urgent need. The laser-TIG hybrid welding technology can play the respective advantages of both of them. One major advantage of the hybrid laser-TIG welding technology is its efficient use of laser energy. Additionally, it can develop into a high and new advanced welding technology and become a hot spot in both the application and research area. This thesis investigated laser –TIG hybrid welding with the aim of enlightening the reader on its advantages, disadvantages and future areas of improvement. The main objective is to investigate laser-TIG hybrid on the welding of various metals (steels, magnesium, aluminium etc.). In addition, it elaborates on various possible combinations on hybrid laser-TIG welding technology and their benefits. The possibility of using laser-TIG hybrid in welding of thick materials was investigated. The method applied in carrying out this research is by using literature review. The results showed that hybrid laser-TIG is applicable to almost all weldable metals. Also it proves to be effective in welding refractive metals. The possibility of welding with or without filler materials is of economic advantage especially in welding of materials with no filler material. Thick plate’s hybrid laser-TIG welding is showing great prospects although it normally finds its used in welding thin materials in the range of 0.4 to 0.8 mm. The findings show that laser-TIG hybrid welding can be a versatile welding process and therefore will be increasingly used industrially due to its numerous advantages and the development of new TIG arc that enhances its capabilities.

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The experiences of the United States Armed Forces of the wars in Iraq and Afghanistan and Israel Defense Forces in the Second Lebanon War resulted a new term to surface called “hybrid warfare”. It was to describe the complexity of today’s battlefield. The term “hy-brid warfare” was never officially defined nor is it today. The updated version of the US ARMY Field Manual 3-0: Operations (Change 1) from February 22, 2011, introduced and defined “hybrid threat” and thus opened the discussion for hybrid adversary. In this thesis a model is introduced according to which any organization, group or an ad-versary can be examined and evaluated to see whether it qualifies as a hybrid adversary. It is demonstrated by the example of Hezbollah, which is recognized as the best example of an organization utilizing “hybrid warfare” and subsequently categorizing as a hybrid adver-sary. The model will be tested with Afghan Taliban to see whether both the model works and Taliban qualifies as a hybrid adversary or not. According to the model used in this thesis, it is concluded that Taliban does not meet the standards of a hybrid adversary, but with acquisition of standoff weapons it would quickly qualify as one. The model proved to work, and it could be used as a tool by intelligence of-ficers for estimating the threat levels of any group or identifying those groups that are al-ready or are about to develop into a hybrid adversary.

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At present, permanent magnet synchronous generators (PMSGs) are of great interest. Since they do not have electrical excitation losses, the highly efficient, lightweight and compact PMSGs equipped with damper windings work perfectly when connected to a network. However, in island operation, the generator (or parallel generators) alone is responsible for the building up of the network and maintaining its voltage and reactive power level. Thus, in island operation, a PMSG faces very tight constraints, which are difficult to meet, because the flux produced by the permanent magnets (PMs) is constant and the voltage of the generator cannot be controlled. Traditional electrically excited synchronous generators (EESGs) can easily meet these constraints, because the field winding current is controllable. The main drawback of the conventional EESG is the relatively high excitation loss. This doctoral thesis presents a study of an alternative solution termed as a hybrid excitation synchronous generator (HESG). HESGs are a special class of electrical machines, where the total rotor current linkage is produced by the simultaneous action of two different excitation sources: the electrical and permanent magnet (PM) excitation. An overview of the existing HESGs is given. Several HESGs are introduced and compared with the conventional EESG from technical and economic points of view. In the study, the armature-reaction-compensated permanent magnet synchronous generator with alternated current linkages (ARC-PMSG with ACL) showed a better performance than the other options. Therefore, this machine type is studied in more detail. An electromagnetic design and a thermal analysis are presented. To verify the operation principle and the electromagnetic design, a down-sized prototype of 69 kVA apparent power was built. The experimental results are demonstrated and compared with the predicted ones. A prerequisite for an ARC-PMSG with ACL is an even number of pole pairs (p = 2, 4, 6, …) in the machine. Naturally, the HESG technology is not limited to even-pole-pair machines. However, the analysis of machines with p = 3, 5, 7, … becomes more complicated, especially if analytical tools are used, and is outside the scope of this thesis. The contribution of this study is to propose a solution where an ARC-PMSG replaces an EESG in electrical power generation while meeting all the requirements set for generators given for instance by ship classification societies, particularly as regards island operation. The maximum power level when applying the technology studied here is mainly limited by the economy of the machine. The larger the machine is, the smaller is the efficiency benefit. However, it seems that machines up to ten megawatts of power could benefit from the technology. However, in low-power applications, for instance in the 500 kW range, the efficiency increase can be significant.

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Diplomityön tarkoitus on tehostaa lämmityslinjan kokoonpanosoluja käyttämällä erilaisia Lean – työkaluja. Pyrkimys on lisätä järjestystä 5S - työkalun avulla sekä selvittää lämmitinlinjan työntekijän ajankäyttö. Lämmitinlinjan suurimmat ongelmat selvitetään häviön mittauksen ja kartoituksen avulla. Työntekijöiden työmenetelmät tutkitaan käyttämällä MTM (Methods-Time Measurement)– menetelmää, jossa yksittäinen työsuoritus kuvataan videolle. Video pisteytetään ja työntekijän liikkeet analysoidaan. Videon pohjalta havaitaan kehityskohteet työpisteissä ja työmenetelmissä, ja ne organisoidaan sekä standardoidaan uudestaan. Materiaalivirtauksen ongelma ratkaistaan siirtämällä komponentit kokoonpanosoluun uuden materiaalipalvelijan toimesta. Menetelmäkehityksen ja paremman järjestyksen avulla kokoonpanosolun tuottavuutta parannetaan 30 prosenttia verrattuna alkuperäiseen tilanteeseen. Lämmitinlinjan häviön mittauksella saavutetaan ymmärrys osaston suurimmista pullonkauloista. Mittauksen avulla tiedetään yksittäisten ongelmien esiintymistiheydet ja koneiden kapasiteettihäviöt. Lämmitinlinjaston tehostaminen tulevaisuudessa vaatii häviöiden alkuperäisten ongelmien ratkaisua.

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Työssä käydään läpi tukivektorikoneiden teoreettista pohjaa sekä tutkitaan eri parametrien vaikutusta spektridatan luokitteluun.

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The Arctic region becoming very active area of the industrial developments since it may contain approximately 15-25% of the hydrocarbon and other valuable natural resources which are in great demand nowadays. Harsh operation conditions make the Arctic region difficult to access due to low temperatures which can drop below -50 °C in winter and various additional loads. As a result, newer and modified metallic materials are implemented which can cause certain problems in welding them properly. Steel is still the most widely used material in the Arctic regions due to high mechanical properties, cheapness and manufacturability. Moreover, with recent steel manufacturing development it is possible to make up to 1100 MPa yield strength microalloyed high strength steel which can be operated at temperatures -60 °C possessing reasonable weldability, ductility and suitable impact toughness which is the most crucial property for the Arctic usability. For many years, the arc welding was the most dominant joining method of the metallic materials. Recently, other joining methods are successfully implemented into welding manufacturing due to growing industrial demands and one of them is the laser-arc hybrid welding. The laser-arc hybrid welding successfully combines the advantages and eliminates the disadvantages of the both joining methods therefore produce less distortions, reduce the need of edge preparation, generates narrower heat-affected zone, and increase welding speed or productivity significantly. Moreover, due to easy implementation of the filler wire, accordingly the mechanical properties of the joints can be manipulated in order to produce suitable quality. Moreover, with laser-arc hybrid welding it is possible to achieve matching weld metal compared to the base material even with the low alloying welding wires without excessive softening of the HAZ in the high strength steels. As a result, the laser-arc welding methods can be the most desired and dominating welding technology nowadays, and which is already operating in automotive and shipbuilding industries with a great success. However, in the future it can be extended to offshore, pipe-laying, and heavy equipment industries for arctic environment. CO2 and Nd:YAG laser sources in combination with gas metal arc source have been used widely in the past two decades. Recently, the fiber laser sources offered high power outputs with excellent beam quality, very high electrical efficiency, low maintenance expenses, and higher mobility due to fiber optics. As a result, fiber laser-arc hybrid process offers even more extended advantages and applications. However, the information about fiber or disk laser-arc hybrid welding is very limited. The objectives of the Master’s thesis are concentrated on the study of fiber laser-MAG hybrid welding parameters in order to understand resulting mechanical properties and quality of the welds. In this work only ferrous materials are reviewed. The qualitative methodological approach has been used to achieve the objectives. This study demonstrates that laser-arc hybrid welding is suitable for welding of many types, thicknesses and strength of steels with acceptable mechanical properties along very high productivity. New developments of the fiber laser-arc hybrid process offers extended capabilities over CO2 laser combined with the arc. This work can be used as guideline in hybrid welding technology with comprehensive study the effect of welding parameter on joint quality.

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The power rating of wind turbines is constantly increasing; however, keeping the voltage rating at the low-voltage level results in high kilo-ampere currents. An alternative for increasing the power levels without raising the voltage level is provided by multiphase machines. Multiphase machines are used for instance in ship propulsion systems, aerospace applications, electric vehicles, and in other high-power applications including wind energy conversion systems. A machine model in an appropriate reference frame is required in order to design an efficient control for the electric drive. Modeling of multiphase machines poses a challenge because of the mutual couplings between the phases. Mutual couplings degrade the drive performance unless they are properly considered. In certain multiphase machines there is also a problem of high current harmonics, which are easily generated because of the small current path impedance of the harmonic components. However, multiphase machines provide special characteristics compared with the three-phase counterparts: Multiphase machines have a better fault tolerance, and are thus more robust. In addition, the controlled power can be divided among more inverter legs by increasing the number of phases. Moreover, the torque pulsation can be decreased and the harmonic frequency of the torque ripple increased by an appropriate multiphase configuration. By increasing the number of phases it is also possible to obtain more torque per RMS ampere for the same volume, and thus, increase the power density. In this doctoral thesis, a decoupled d–q model of double-star permanent-magnet (PM) synchronous machines is derived based on the inductance matrix diagonalization. The double-star machine is a special type of multiphase machines. Its armature consists of two three-phase winding sets, which are commonly displaced by 30 electrical degrees. In this study, the displacement angle between the sets is considered a parameter. The diagonalization of the inductance matrix results in a simplified model structure, in which the mutual couplings between the reference frames are eliminated. Moreover, the current harmonics are mapped into a reference frame, in which they can be easily controlled. The work also presents methods to determine the machine inductances by a finite-element analysis and by voltage-source inverters on-site. The derived model is validated by experimental results obtained with an example double-star interior PM (IPM) synchronous machine having the sets displaced by 30 electrical degrees. The derived transformation, and consequently, the decoupled d–q machine model, are shown to model the behavior of an actual machine with an acceptable accuracy. Thus, the proposed model is suitable to be used for the model-based control design of electric drives consisting of double-star IPM synchronous machines.

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Bestraffning av internationella brott vid internationella och hybrida straffrättsliga domstolar har traditionellt och huvudsakligen grundat sig på principen om retributiv (vedergällande) rättvisa och ackusatorisk process snarare än återuppbyggande rättvisa och en inkvisitorisk modell. Därav har brottsoffrens ställning vid dessa straffrättsliga domstolar begränsat sig till den som innehas av vittnen vid Tribunalen som behandlar brott som begåtts i det forna Jugoslavien (ICTY), Internationella krigsförbrytartribunalen för Rwanda (ICTR) och Specialdomstolen för Sierra Leone (SCSL). Internationella brottmålsdomstolen (ICC), å sin sida, har medfört en viktig förändring gällande brottsoffrens ställning i internationella straffrättsliga fora, vilket innebär att de från att ha betraktats endast i egenskap av vittnen nu även har en rätt att delta och lämna sina synpunkter (i egenskap av brottsofferdeltagare) samt kräva gottgörelse. Denna trend har fortsatt inom området för internationell straffrätt, vilket manifesterats vid hybridtribunaler som tillsatts efter ICC såsom Kambodjadomstolen (ECCC) vid vilken brottsoffer kan agera civilrättsliga parter och Specialdomstolen för Libanon (STL) där brottsoffer kan inneha en deltagande roll. Den föreliggande studien behandlar två huvudsakliga frågeställningar, av vilka den första lyder: Vilken ställning tillskrivs brottsoffren vid internationella domstolar och hybridtribunaler? I detta hänseende argumenterar författaren, sammanfattningsvis, för att brottsoffrens ställning vid internationella straffrättsliga domstolar och hybridtribunaler huvudsakligen tar sig uttryck på tre sätt, d.v.s. som brottsoffer i egenskap av vittnen, som brottsoffer i egenskap av deltagande brottsoffer/civilrättsliga parter samt som brottsoffer som kräver gottgörelse. Den andra frågeställningen för denna studie lyder: På vilket sätt fungerar brottsoffrens ställning som vittnen, brottsofferdeltagande/civilrättsliga parter och gottgörelsekrävande vid internationella och hybrida straffrättsliga domstolar? -------------------------------------------------------------------------------------------------------------------------------------------------- Kansainvälisten rikosten rankaiseminen kansainvälisissä rikostuomioistuimissa ja hybridituomioistuimissa on perinteisesti enimmäkseen perustunut retributiivisen oikeuden ja akkusatorisen menetelmän soveltamiseen pikemmin kuin restoratiivisen oikeuden ja inkvisitorisen menetelmän soveltamiseen. Niinpä uhrien asema kansainvälisissä rikostuomioistuimissa ja hybridituomioistuimissa on rajoittunut todistajan asemaan entisen Jugoslavian kansainvälisessä sotarikostuomioistuimessa (ICTY), Ruandan kansainvälisessä sotarikostuomioistuimessa (ICTR) ja Sierra Leonen erikoistuomioistuimessa (SCSL). Kansainvälisen rikostuomioistuimen (ICC) perustaminen on kuitenkin merkinnyt tärkeää muutosta uhrien asemaan kansainvälisen rikosoikeuden alalla siten, että kun uhrit aiemmin nähtiin vain todistajina, heillä on nyt myös mahdollisuus tuoda esiin omat näkökantansa (osallistumisoikeus) ja vaatia hyvitystä. Tämä suuntaus on jatkunut kansainvälisen rikosoikeuden alalla ICC:n jälkeen perustetuissa hybridituomioistuimissa, kuten Kambodzhan erityistuomioistuimessa (ECCC), missä uhrit voivat olla asianosaisen asemassa, sekä Libanonin erityistuomioistuimessa (STL), missä uhrit voivat osallistua prosessiin. Tämä tutkimus käsittelee kahta keskeistä kysymystä. Ensinnäkin: Mikä on rikoksen uhrien asema kansainvälisissä rikostuomioistuimissa ja hybridituomioistuimissa? Tutkimuksessa päädytään mm. siihen, että uhrien asema kansainvälisissä rikostuomioistuimissa ja hybridituomioistuimissa voi koostua pääosin kolmesta ulottuvuudesta eli uhrit todistajina, uhrit prosessiin osallistujina/asianosaisina ja uhrit hyvityksen hakijoina. Tutkimuksen toinen keskeinen kysymys on: Miten uhrien asema todistajina, prosessiin osallistujina/ asianosaisina ja hyvityksen hakijoina toimii kansainvälisissä rikostuomioistuimissa ja hybridituomioistuimissa?