59 resultados para Joint element


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Being highly discussed the problem of climate change and global warming has been keeping importance for several of decades. As a response to the world’s need in solution for climate change disasters, the United Nations Framework Convention on Climate Change was adopted in 1992 and supplemented with the Kyoto protocol in 1997. This work is aimed to give better understanding of the Convention, Kyoto Protocol with its mechanisms and their function, related to energy projects in such case countries, as Russia and China, in order to assist evaluation of projects cost-effectiveness. It provides basic information about the Convention and the Protocol with their regulations, overview of present situation and future post-Kyoto forecasts, while the most attention is concentrated on the clean development mechanism and joint implementation step-by-step project cycles and specific regulations in given countries. The current study disclosed that CDM and JI project cycles are resulting in a complicated process. By the moment it requires step-by-step following of a number of methodologies, spending time and finance to particular project development. Uncertainties about post-Kyoto period bring additional risk to the projects and complicate any business decision concerning Kyoto Protocol.

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This thesis introduces a real-time simulation environment based on the multibody simulation approach. The environment consists of components that are used in conventional product development, including computer aided drawing, visualization, dynamic simulation and finite element software architecture, data transfer and haptics. These components are combined to perform as a coupled system on one platform. The environment is used to simulate mobile and industrial machines at different stages of a product life time. Consequently, the demands of the simulated scenarios vary. In this thesis, a real-time simulation environment based on the multibody approach is used to study a reel mechanism of a paper machine and a gantry crane. These case systems are used to demonstrate the usability of the real-time simulation environment for fault detection purposes and in the context of a training simulator. In order to describe the dynamical performance of a mobile or industrial machine, the nonlinear equations of motion must be defined. In this thesis, the dynamical behaviour of machines is modelled using the multibody simulation approach. A multibody system may consist of rigid and flexible bodies which are joined using kinematic joint constraints while force components are used to describe the actuators. The strength of multibody dynamics relies upon its ability to describe nonlinearities arising from wearing of the components, friction, large rotations or contact forces in a systematic manner. For this reason, the interfaces between subsystems such as mechanics, hydraulics and control systems of the mechatronic machine can be defined and analyzed in a straightforward manner.

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It is necessary to use highly specialized robots in ITER (International Thermonuclear Experimental Reactor) both in the manufacturing and maintenance of the reactor due to a demanding environment. The sectors of the ITER vacuum vessel (VV) require more stringent tolerances than normally expected for the size of the structure involved. VV consists of nine sectors that are to be welded together. The vacuum vessel has a toroidal chamber structure. The task of the designed robot is to carry the welding apparatus along a path with a stringent tolerance during the assembly operation. In addition to the initial vacuum vessel assembly, after a limited running period, sectors need to be replaced for repair. Mechanisms with closed-loop kinematic chains are used in the design of robots in this work. One version is a purely parallel manipulator and another is a hybrid manipulator where the parallel and serial structures are combined. Traditional industrial robots that generally have the links actuated in series are inherently not very rigid and have poor dynamic performance in high speed and high dynamic loading conditions. Compared with open chain manipulators, parallel manipulators have high stiffness, high accuracy and a high force/torque capacity in a reduced workspace. Parallel manipulators have a mechanical architecture where all of the links are connected to the base and to the end-effector of the robot. The purpose of this thesis is to develop special parallel robots for the assembly, machining and repairing of the VV of the ITER. The process of the assembly and machining of the vacuum vessel needs a special robot. By studying the structure of the vacuum vessel, two novel parallel robots were designed and built; they have six and ten degrees of freedom driven by hydraulic cylinders and electrical servo motors. Kinematic models for the proposed robots were defined and two prototypes built. Experiments for machine cutting and laser welding with the 6-DOF robot were carried out. It was demonstrated that the parallel robots are capable of holding all necessary machining tools and welding end-effectors in all positions accurately and stably inside the vacuum vessel sector. The kinematic models appeared to be complex especially in the case of the 10-DOF robot because of its redundant structure. Multibody dynamics simulations were carried out, ensuring sufficient stiffness during the robot motion. The entire design and testing processes of the robots appeared to be complex tasks due to the high specialization of the manufacturing technology needed in the ITER reactor, while the results demonstrate the applicability of the proposed solutions quite well. The results offer not only devices but also a methodology for the assembly and repair of ITER by means of parallel robots.

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Modern sophisticated telecommunication devices require even more and more comprehensive testing to ensure quality. The test case amount to ensure well enough coverage of testing has increased rapidly and this increased demand cannot be fulfilled anymore only by using manual testing. Also new agile development models require execution of all test cases with every iteration. This has lead manufactures to use test automation more than ever to achieve adequate testing coverage and quality. This thesis is separated into three parts. Evolution of cellular networks is presented at the beginning of the first part. Also software testing, test automation and the influence of development model for testing are examined in the first part. The second part describes a process which was used to implement test automation scheme for functional testing of LTE core network MME element. In implementation of the test automation scheme agile development models and Robot Framework test automation tool were used. In the third part two alternative models are presented for integrating this test automation scheme as part of a continuous integration process. As a result, the test automation scheme for functional testing was implemented. Almost all new functional level testing test cases can now be automated with this scheme. In addition, two models for integrating this scheme to be part of a wider continuous integration pipe were introduced. Also shift from usage of a traditional waterfall model to a new agile development based model in testing stated to be successful.

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The nutrient load to the Gulf of Finland has started to increase as a result of the strong economic recovery in agriculture and livestock farming in the Leningrad region. Also sludge produced from municipal wastewater treatment plant of the Leningrad region causes the great impact on the environment, but still the main options for its treatment is disposal on the sludge beds or Landfills. The aim of this study was to evaluate the implementation of possible joint treatment methods of manure form livestock and poultry enterprises and sewage sludge produced from municipal wastewater treatment plants in the Leningrad region. The study is based on published data. The most attention was put on the anaerobic digestion and incineration methods. The manure and sewage sludge generation for the whole Leningrad region and energy potential produced from their treatment were estimated. The calculations showed that total amount of sewage sludge generation is 1 348 000 t/a calculated on wet matter and manure generation is 3 445 000 t/a calculated on wet matter. The potential heat release from anaerobic digestion process and incineration process is 4 880 000 GJ/a and 5 950 000 GJ/a, respectively. Furthermore, the work gives the overview of the general Russian and Finnish legislation concerning manure and sewage sludge treatment. In the Gatchina district it was chosen the WWTP and livestock and poultry enterprises for evaluation of the centralized treatment plant implementation based on anaerobic digestion and incineration methods. The electricity and heat power of plant based on biogas combustion process is 4.3 MW and 7.8 MW, respectively. The electricity and heat power of plant based on manure and sewage sludge incineration process is 3.0 MW and 6.1 MW, respectively.

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Ultralujat teräkset ovat teräksiä, joiden lujuus on reilusti suurempi verrattuna perinteisiin rakenneteräksiin. Niiden ominaisuuksia hyödynnetään eniten nosto- ja kuljetusvälinete¬ollisuudessa. Ultralujien terästen käyttö avaa suunnittelijalle uusia mahdollisuuksia suun¬nitella ulottuvampia ja kevyempiä rakenteita, jolloin voidaan saavuttaa säästöjä niin val¬mistus- kuin polttoainekustannuksissakin. Ultralujille teräksille ei kuitenkaan ole ole¬massa niitä vastaavia suunnitteluohjeita tai standardeja. Teräsrakenteiden liitosten suun¬nitteluun mitoitusohjeita antava standardi SFS-EN 1993-1-8 ei huomioi teräksiä, joiden myötölujuus on yli 460 MPa. SFS-EN 1993-1-12 on 1993-1-8:n laajennus, joka on voi¬massa myötölujuuteen 700 MPa asti. Tässä diplomityössä tutkittiin ultralujista teräksistä valmistettujen pienahitsiliitosten käyttäytymistä vetokokeiden ja elementtimenetelmän avulla. Tulosten avulla voitiin mää¬rittää matalalujuuksisten terästen mitoitusohjeiden soveltuvuutta ultralujille teräksille. Kokeissa käytetty teräs oli Ruukin valmistama Optim 960 QC.

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The purpose of this study was to develop co-operation between business units of the company operating in graphic industry. The development was done by searching synergy opportunities between these business units. The final aim was to form a business model, which is based on co-operation of these business units.The literature review of this thesis examines synergies and especially the process concerning the search and implementation of synergies. Also the concept of business model and its components are examined. The research was done by using qualitative research method. The main data acquiring method to the empirical part was theme interviews. The data was analyzed using thematisation and content analysis.The results of the study include seven identified possible synergies and a business model, which is based on the co-operation of the business units. The synergy opportunities are evaluated and the implementation order of the synergies is suggested. The presented synergies create the base for the proposed business model.

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Rautaruukki Oyj:n uusi Ruukki double grade S420MH/S355J2H -rakenneputki yhdistää putkilajien S420MH ja S355J2H ominaisuudet. Eurocode 3:n suunnitteluohjeiden mukaan Ruukki double graden käyttöön on sovellettava lujuusluokan S420 mukaista hitsien mitoitusta ja rakenneputkiliitosten staattista mitoituskestävyyttä alentavaa varmuuskerrointa, kun halutaan hyödyntää lujuusluokan S420 ominaisuudet Ruukki double gradea käytettäessä. Tässä työssä tutkittiin S420-lujuusluokkaa vastaavien suunnittelumääräysten soveltamistarvetta Ruukki double grade -rakenneputken käyttöön. Työn tavoitteena oli arvioida Ruukki double grade -rakenneputkesta hitsaamalla valmistetun X-liitoksen kestävyyden ja muodonmuutoskyvyn riittävyys, kun hitsit mitoitettiin S355-lujuusluokkaa vastaavien Eurocode 3:n suunnitteluohjeiden mukaisesti. X-liitosten kestävyyttä ja muodonmuutoskykyä tutkittiin kokeellisesti -40 C lämpötilassa suoritettujen laboratoriokokeiden avulla sekä analyyttisen laskennan ja elementtimenetelmän keinoin. Kestävyyden riittävyyttä arvioitiin vertaamalla laboratoriokokeista saatuja liitosten kestävyyksiä Eurocode 3:n ja myötöviivateorian mukaisiin kestävyyksiin. Elementtimenetelmän ja laboratoriokokeen pohjalta piirrettyjä liitoksen voima-siirtymäkuvaajia vertailtiin keskenään, kun elementtimalli analysoitiin eri materiaalimalleilla. Lisäksi verrattiin elementtimallin voima-venymäkuvaajia liitoksen venymäliuskan arvoihin. Kaikki koesarjan S355-lujuusluokan mukaisilla hitsin a-mitoilla valmistetut liitokset täyttivät kestävyydelle ja muodonmuutoskyvylle asetetut vaatimukset. Täten tämän koesarjan perusteella ei ollut tarpeellista soveltaa S420-lujuusluokan mukaista hitsien mitoitusta ja staattista mitoituskestävyyttä alentavaa varmuuslukua Ruukki double grade -rakenneputkeen. Elementtimenetelmästä ja laboratoriokokeesta saadut liitoksen voima-siirtymäkuvaajat vastasivat hyvin toisiaan. Sen sijaan elementtimallin voima-venymä-kuvaajat eivät vastanneet venymäliuskojen mittausdataa kovin hyvin.

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Alumiiniveneissä hitsauksen aiheuttamat muodonmuutokset ovat usein erittäin haitallisia, koska niiden aiheuttamat mittamuutokset ja ulkonäölliset haitat alentavat tuotteen laatua sekä arvoa. Monissa tapauksissa myös hitsausliitoksen suorituskyky heikentyy ja lisäksi hitsausmuodonmuutokset voivat aiheuttaa toiminnallisia ongelmia alumiiniveneiden runkorakenteisiin. Tästä johtuen hitsausmuodonmuutosten hallinta ja minimointi ovat erityisen tärkeitä tekijöitä pyrittäessä parantamaan alumiiniveneiden laatua ja kustannustehokkuutta sekä kasvattamaan alumiinivenealan kilpailukykyä. Tässä diplomityössä tutkittiin robotisoidun kaasukaarihitsauksen aiheuttamia muodonmuutoksia sekä niiden hallintaa alumiinista valmistettujen työ- ja huviveneiden runkorakenteissa. Työssä perehdyttiin nykyaikaiseen alumiinivenevalmistukseen sekä hitsattujen rakenteiden yleisiin lujuusopin teorioihin ja käyttäytymismalleihin. Alumiinin hitsausmuodonmuutosten tutkimuksissa suoritettiin käytännön hitsauskokeita, joiden kohteina olivat alumiiniveneissä käytetyt rakenneratkaisut ja liitostyypit. Työn tavoitteena oli määrittää alumiinin hitsauksessa syntyviin muodonmuutoksiin keskeisesti vaikuttavia tekijöitä ja parametreja. Tutkimustulosten perusteella pyrittiin esittämään ratkaisuja alumiiniveneiden rakenteisiin aiheutuvien hitsausmuodonmuutosten vähentämiseksi ja hallitsemiseksi. Alumiinirakenteissa hitsausmuodonmuutokset ovat hyvin tapauskohtaisia, koska usein niiden syntyminen määräytyy monen tekijän yhteisvaikutuksesta. Teräsrakenteille käytetyt yleiset analyyttiset laskentakaavat ja käyttäytymismallit eivät sovellu suoraan alumiinirakenteille, mikä johtuu alumiinin erilaisista materiaaliominaisuuksista ja käyttäytymisestä hitsauksen aikana. Tulevaisuudessa empiiristen koejärjestelyiden ja analyyttisten mallien lisäksi sovellettavan numeerisen elementtimenetelmän avulla voidaan parantaa alumiinin hitsauksessa aiheutuvien muodonmuutosten kokonaisvaltaista hallintaa.

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Viipurinlahden taistelun kesällä 1944 on monesti esitetty olevan ensimmäinen suomalainen joint- eli yhteisoperaatio. Työ käsittelee Viipurinlahden taistelua nykyaikaisen jointoperaation periaatteiden näkökulmasta. Viipurinlahden taistelussa toimi kaikkien kolmen puolustushaaran joukkoja pienellä taistelualueella. Joint-käsitettä tarkastellaan yhdysvaltalaisten ohjesääntöjen ja suomalaisten näkemysten kautta. Yhdysvallat on yksi maailman johtavin joint-doktriinin käyttäjä. Tämän vuoksi joint-käsitettä tarkastellaan työssä pääasiassa Yhdysvaltojen ohjesääntöjen ja niihin perustuvan tiedon kautta.

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Hitsatuissa rakenteissa on paljon hitsien aiheuttamia epäjatkuvuuskohtia, jotka ovat alttiita vaurioitumaan väsyttävän kuormituksen alaisina. Standardit ja normit auttavat suunnittelua rakenneyksityiskohtien analysoinnissa, mutta ohjeiden arvot vaihtelevat paljon. Onkin tär-keää päättää, mitä standardia tai normia käytetään ja saada tutkimustuloksia tukemaan ohjeen käyttöä. Tämä työ on tehty Konecranes Finland Oy:lle. Työn tarkoituksena on etsiä käytössä olevi-en ohjeiden joukosta suunnittelun kannalta parhaiten todellista rakennetta kuvaava. Työssä esitellään käytössä olevia standardeja ja normeja sekä vertaillaan niiden välisiä eroja rakenneyksityiskohdan väsymiskestävyyden määrittämisessä. Työssä tarkastellaan myös hitsatun rakenteen väsymiseen vaikuttavia tekijöitä sekä väsymisanalyysissä käytet-täviä menetelmiä. Tutkittavaan liitokseen valittiin kolme erilaista hitsiä, yksi –ja kaksipuolinen pienahitsi sekä katkopienahitsi. Elementtimenetelmän avulla luotiin malleja koekappaleista ja laskettiin niille väsymiskestävyydet. Tämä lisäksi väsymistä tarkasteltiin väsytyskokeilla, jotka suoritti Lappeenrannan Teknillisen Yliopiston Teräsrakenteiden laboratorio. Lopputuloksena työstä saatiin tietoa hitsien väsymiskestävyyksistä. Liitosten väsymiskes-tävyydet olivat hyviä ja varsinkin katkopienahitsin tulokset olivat odotettua paremmat. Kat-kopienahitsin väsymiskestävyys vaatii tämän työn tulosten perusteella lisää tutkimista.

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The bioavailability of metals and their potential for environmental pollution depends not simply on total concentrations, but is to a great extent determined by their chemical form. Consequently, knowledge of aqueous metal species is essential in investigating potential metal toxicity and mobility. The overall aim of this thesis is, thus, to determine the species of major and trace elements and the size distribution among the different forms (e.g. ions, molecules and mineral particles) in selected metal-enriched Boreal river and estuarine systems by utilising filtration techniques and geochemical modelling. On the basis of the spatial physicochemical patterns found, the fractionation and complexation processes of elements (mainly related to input of humic matter and pH-change) were examined. Dissolved (<1 kDa), colloidal (1 kDa-0.45 μm) and particulate (>0.45 μm) size fractions of sulfate, organic carbon (OC) and 44 metals/metalloids were investigated in the extremely acidic Vörå River system and its estuary in W Finland, and in four river systems in SW Finland (Sirppujoki, Laajoki, Mynäjoki and Paimionjoki), largely affected by soil erosion and acid sulfate (AS) soils. In addition, geochemical modelling was used to predict the formation of free ions and complexes in these investigated waters. One of the most important findings of this study is that the very large amounts of metals known to be released from AS soils (including Al, Ca, Cd, Co, Cu, Mg, Mn, Na, Ni, Si, U and the lanthanoids) occur and can prevail mainly in toxic forms throughout acidic river systems; as free ions and/or sulfate-complexes. This has serious effects on the biota and especially dissolved Al is expected to have acute effects on fish and other organisms, but also other potentially toxic dissolved elements (e.g. Cd, Cu, Mn and Ni) can have fatal effects on the biota in these environments. In upstream areas that are generally relatively forested (higher pH and contents of OC) fewer bioavailable elements (including Al, Cu, Ni and U) may be found due to complexation with the more abundantly occurring colloidal OC. In the rivers in SW Finland total metal concentrations were relatively high, but most of the elements occurred largely in a colloidal or particulate form and even elements expected to be very soluble (Ca, K, Mg, Na and Sr) occurred to a large extent in colloidal form. According to geochemical modelling, these patterns may only to a limited extent be explained by in-stream metal complexation/adsorption. Instead there were strong indications that the high metal concentrations and dominant solid fractions were largely caused by erosion of metal bearing phyllosilicates. A strong influence of AS soils, known to exist in the catchment, could be clearly distinguished in the Sirppujoki River as it had very high concentrations of a metal sequence typical of AS soils in a dissolved form (Ba, Br, Ca, Cd, Co, K, Mg, Mn, Na, Ni, Rb and Sr). In the Paimionjoki River, metal concentrations (including Ba, Cs, Fe, Hf, Pb, Rb, Si, Th, Ti, Tl and V; not typical of AS soils in the area) were high, but it was found that the main cause of this was erosion of metal bearing phyllosilicates and thus these metals occurred dominantly in less toxic colloidal and particulate fractions. In the two nearby rivers (Laajoki and Mynäjoki) there was influence of AS soils, but it was largely masked by eroded phyllosilicates. Consequently, rivers draining clay plains sensitive to erosion, like those in SW Finland, have generally high background metal concentrations due to erosion. Thus, relying on only semi-dissolved (<0.45 μm) concentrations obtained in routine monitoring, or geochemical modelling based on such data, can lead to a great overestimation of the water toxicity in this environment. The potentially toxic elements that are of concern in AS soil areas will ultimately be precipitated in the recipient estuary or sea, where the acidic metalrich river water will gradually be diluted/neutralised with brackish seawater. Along such a rising pH gradient Al, Cu and U will precipitate first together with organic matter closest to the river mouth. Manganese is relatively persistent in solution and, thus, precipitates further down the estuary as Mn oxides together with elements such as Ba, Cd, Co, Cu and Ni. Iron oxides, on the contrary, are not important scavengers of metals in the estuary, they are predicted to be associated only with As and PO4.

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This thesis describes the process of design and modeling of instrument for knee joint kinematics measurement that can work for both in-vivo and in-vitro subjects. It is designed to be compatible with imaging machine in a sagittal plane. Due to the invasiveness of the imaging machine, the instrument is designed to be able to function independently. The flexibility of this instrument allows to measure anthropometrically different subject. Among the sixth degree of freedom of a knee, three rotational and one translational degree of freedom can be measured for both type of subject. The translational, proximal-distal, motion is stimulated by external force directly applied along its axis. These angular and linear displacements are measured by magnetic sensors and high precision potentiometers respectively

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With information technology (IT) playing an increasing important role in driving the business, the value of IT investment is often challenged because not all of those investment decisions are made in a reasonable way or aligned with business strategies. IT investment portfolio management (PfM) is an effective way to prioritize and select the right IT projects to invest in, by taking all the project proposals into consideration as a whole, based on their business value, risks, costs, and interrelationships. There are different decision models to prioritise projects, and the Analytic Hierarchy Process (AHP) is one of the most commonly-used methods and is discussed in this master thesis. At the same time, there are IT projects on different levels for a multinational company, from global to local. For instance, many of them are probably proposed by joint ventures on local level. In the oil & gas industry, joint ventures are often formed especially in the area of the upstream (exploration & production). How to involve those projects into the IT investment PfM approach of the parent company is a challenge, because the parent company cannot make the decisions on its own. It needs to prioritize all projects in an adequate way, communicate with JVs and influence them. Also, different control levels on JVs need to be considered. This paper hence attempts to introduce a tailored approach of IT investment PfM for a multinational oil & gas company to address the issues around JVs.