698 resultados para Lappeenranta University of Technology


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The liberalisation of the wholesale electricity markets has been considered an efficient way to organise the markets. In Europe, the target is to liberalise and integrate the common European electricity markets. However, insufficient transmission capacity between the market areas hampers the integration, and therefore, new investments are required. Again, massive transmission capacity investments are not usually easy to carry through. This doctoral dissertation aims at elaborating on critical determinants required to deliver the necessary transmission capacity investments. The Nordic electricity market is used as an illustrative example. This study suggests that changes in the governance structure have affected the delivery of Nordic cross-border investments. In addition, the impacts of not fully delivered investments are studied in this doctoral dissertation. An insufficient transmission network can degrade the market uniformity and may also cause a need to split the market into smaller submarkets. This may have financial impacts on market actors when the targeted efficient sharing of resources is not met and even encourage gaming. The research methods applied in this doctoral dissertation are mainly empirical ranging from a Delphi study to case studies and numerical calculations.

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Diplomityössä tutkitaan virtauksen kääntymistä Lappeenrannan teknillisen yliopiston PWR PACTEL –koelaitteiston pystyhöyrystimen lämmönvaihtoputkissa käyttäen APROS–prosessisimulointiohjelmaa. Työn teoriaosassa esitellään pystyhöyrystimillä varustettuja koelaitteistoja, erityisesti PWR PACTEL ja sen höyrystin. Lisäksi esitellään virtauksen kääntymisestä tehtyjä havaintoja ja käsitellään kääntymistä teoreettisesta näkökulmasta. Simulointiosan alussa esitellään työssä käytetty APROS –prosessisimulointiohjelma, sekä sen avulla höyrystimestä luodut mallit. Työssä on tutkittu virtauksen käännöstapahtumaa simuloimalla useita eri transienttitilanteita pienillä primäärimassavirroilla. Simulaatiotapauksissa havaittiin virtauksen kääntyvän höyrystimen eripituisissa lämmönvaihtoputkissa, tilanteesta riippuen pääosin lyhimmissä tai toisiksi lyhimmissä lämmönvaihtoputkissa. Transienttien eri vaiheiden, ts. primäärimassavirran muutos- ja tasaantumisvaiheiden pituuden havaittiin vaikuttavan siihen, minkä pituisissa putkissa kääntyminen tapahtuu ja missä järjestyksessä.

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Wood-based bioprocesses present one of the fields of interest with the most potential in the circular economy. Expanding the use of wood raw material in sustainable industrial processes is acknowledged on both a global and a regional scale. This thesis concerns the application of a capillary zone electrophoresis (CZE) method with the aim of monitoring wood-based bioprocesses. The range of detectable carbohydrate compounds is expanded to furfural and polydatin in aquatic matrices. The experimental portion has been conducted on a laboratory scale with samples imitating process samples. This thesis presents a novel strategy for the uncertainty evaluation via in-house validation. The focus of the work is on the uncertainty factors of the CZE method. The CZE equipment is sensitive to ambient conditions. Therefore, a proper validation is essential for robust application. This thesis introduces a tool for process monitoring of modern bioprocesses. As a result, it is concluded that the applied CZE method provides additional results to the analysed samples and that the profiling approach is suitable for detecting changes in process samples. The CZE method shows significant potential in process monitoring because of the capability of simultaneously detecting carbohydrate-related compound clusters. The clusters can be used as summary terms, indicating process variation and drift.

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Keskustelu yrittäjyyden sijoittumisesta yliopistojen tehtäväkenttään on muodostunut 2000-luvun aikana osaksi yhteiskunnallista ja maailmanlaajuista korkeakoulutuksen muutosta. Tämän tutkimuksen tarkoituksena on lisätä ymmärrystä yliopiston yrittäjämäisyyden sosiaalisesta rakentumisesta. Lähestyn yliopiston sisällä tuotettua moniäänistä yrittäjyyspuhetta yliopiston yrittäjämäisyyden todellisuuden representaationa, ja pyrin tekemään siitä selkoa kommunikaatioon kohdistuvan analyysin avulla. Ilmiön empiirinen tarkastelu pohjautuu Aalto-yliopistossa ja sitä edeltäneessä Teknillisessä korkeakoulussa vuosina 2006–2013 kerättyihin tekstiaineistoihin. Aineistojen tulkinta tuottaa monikerroksellista tietoa ilmiöstä niin yksilö- kuin organisaatiotasolla. Tarkastelen tutkimuksessani millaisia merkityksenantoja yrittäjyydelle ja yrittäjämäisyydelle annetaan yliopiston sisällä eri näkökulmista katsottuna, kun yliopisto käy läpi merkittävää organisaatiorakenteellista ja institutionaalista muutosta. Tutkimusasetelman neljä näkökulmaa perustuvat tekniikan alan jatko-opiskelijoiden puheeseen, TKK:n opetussuunnitelmatekstiin, Aalto-yliopiston opettajien puheeseen ja johdon tuottamaan strategiatekstiaineistoon. Tutkimuksen tulosten mukaan käynnissä on ollut akateemisten arvojen ja arvojärjestelmien laajentumisen aika ja tila, jossa yrittäjämäisyys astuu areenalle, mutta sen suppeat tulkinnat eivät tarjoa mahdollisuuksia ruohonjuuritason kiinnittymiseen akateemisesta kulttuurista käsin. Yrittäjyyden ja yrittäjämäisyyden saamat taloudelliskaupalliset merkitykset koetaan uhkaksi, eikä tilannetta helpota yleisesti uuvuttavaksi koettu rakenteellinen ja yhteiskunnallinen yliopiston muutosvaihe. Hallitsevat tarinalinjat kuten puhe kilpailukyvystä ja kilpailutilanteen kovenemisesta tuottavat odotusten viitekehyksen, joilla yliopiston toimintaa raamitetaan ulkoapäin. Yrittäjyyteen laajassa merkityksessä sisältyvät mahdollisuudet jäävät niin ikään hyödyntämättä, ja lukuisat edistämistoiminnot kilpistyvät sosiaalisesti rakentuviin esteisiin. Tässä tutkimuksessa rakentuva laajennettu yliopiston yrittäjämäisyyden viitekehys pyrkii palvelemaan moniäänistymisen tarkoitusta käsitteellisellä tasolla ja avaamaan uusia mahdollisuuksia yliopiston yrittäjämäisyyden edistämiselle.

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Object detection is a fundamental task of computer vision that is utilized as a core part in a number of industrial and scientific applications, for example, in robotics, where objects need to be correctly detected and localized prior to being grasped and manipulated. Existing object detectors vary in (i) the amount of supervision they need for training, (ii) the type of a learning method adopted (generative or discriminative) and (iii) the amount of spatial information used in the object model (model-free, using no spatial information in the object model, or model-based, with the explicit spatial model of an object). Although some existing methods report good performance in the detection of certain objects, the results tend to be application specific and no universal method has been found that clearly outperforms all others in all areas. This work proposes a novel generative part-based object detector. The generative learning procedure of the developed method allows learning from positive examples only. The detector is based on finding semantically meaningful parts of the object (i.e. a part detector) that can provide additional information to object location, for example, pose. The object class model, i.e. the appearance of the object parts and their spatial variance, constellation, is explicitly modelled in a fully probabilistic manner. The appearance is based on bio-inspired complex-valued Gabor features that are transformed to part probabilities by an unsupervised Gaussian Mixture Model (GMM). The proposed novel randomized GMM enables learning from only a few training examples. The probabilistic spatial model of the part configurations is constructed with a mixture of 2D Gaussians. The appearance of the parts of the object is learned in an object canonical space that removes geometric variations from the part appearance model. Robustness to pose variations is achieved by object pose quantization, which is more efficient than previously used scale and orientation shifts in the Gabor feature space. Performance of the resulting generative object detector is characterized by high recall with low precision, i.e. the generative detector produces large number of false positive detections. Thus a discriminative classifier is used to prune false positive candidate detections produced by the generative detector improving its precision while keeping high recall. Using only a small number of positive examples, the developed object detector performs comparably to state-of-the-art discriminative methods.

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If electricity users adjusted their consumption patterns according to time-variable electricity prices or other signals about the state of the power system, generation and network assets could be used more efficiently, and matching intermittent renewable power generation with electricity demand would be facilitated. This kind of adjustment of electricity consumption, or demand response, may be based on consumers’ decisions to shift or reduce electricity use in response to time-variable electricity prices or on the remote control of consumers’ electric appliances. However, while demand response is suggested as a solution to many issues in power systems, actual experiences from demand response programs with residential customers are mainly limited to short pilots with a small number of voluntary participants, and information about what kinds of changes consumers are willing and able to make and what motivates these changes is scarce. This doctoral dissertation contributes to the knowledge about what kinds of factors impact on residential consumers’ willingness and ability to take part in demand response. Saving opportunities calculated with actual price data from the Finnish retail electricity market are compared with the occurred supplier switching to generate a first estimate about how large savings could trigger action also in the case of demand response. Residential consumers’ motives to participate in demand response are also studied by a web-based survey with 2103 responses. Further, experiences of households with electricity consumption monitoring systems are discussed to increase knowledge about consumers’ interest in getting more information on their electricity use and adjusting their behavior based on it. Impacts of information on willingness to participate in demand response programs are also approached by a survey for experts of their willingness to engage in demand response activities. Residential customers seem ready to allow remote control of electric appliances that does not require changes in their everyday routines. Based on residents’ own activity, the electricity consuming activities that are considered shiftable are very limited. In both cases, the savings in electricity costs required to allow remote control or to engage in demand response activities are relatively high. Nonmonetary incentives appeal to fewer households.

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The current thesis manuscript studies the suitability of a recent data assimilation method, the Variational Ensemble Kalman Filter (VEnKF), to real-life fluid dynamic problems in hydrology. VEnKF combines a variational formulation of the data assimilation problem based on minimizing an energy functional with an Ensemble Kalman filter approximation to the Hessian matrix that also serves as an approximation to the inverse of the error covariance matrix. One of the significant features of VEnKF is the very frequent re-sampling of the ensemble: resampling is done at every observation step. This unusual feature is further exacerbated by observation interpolation that is seen beneficial for numerical stability. In this case the ensemble is resampled every time step of the numerical model. VEnKF is implemented in several configurations to data from a real laboratory-scale dam break problem modelled with the shallow water equations. It is also tried in a two-layer Quasi- Geostrophic atmospheric flow problem. In both cases VEnKF proves to be an efficient and accurate data assimilation method that renders the analysis more realistic than the numerical model alone. It also proves to be robust against filter instability by its adaptive nature.

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Additive manufacturing, or 3D printing, is globally one of most interesting area in developing of manufacturing technologies. This technology is suitable for fabrication off industrial products and it interests actors in fields of computer sciences, economics, medical sciences and design&arts. Additive manufacturing is often referred as third industrial revolution: first revolution was invention of steam engines in 18th century and second was industrial revolution started by Henry Ford in 1920s. Companies should be able to test suitability of their products for additive manufacturing and 3D printing but also how much better products could be when products are totally re-designed so that all potential of this new technology can be utilized. This is where education has its importance; new generations who enter working life should be educated to know of additive manufacturing and 3D printing, its advantages but also of it limits. There has to be also possibility to educate industry and people already working there, so that industrial implementation could be done successfully. This is especially very valid for Finland. Education is strongly needed so that Finnish industry can maintain its competence in global markets. Role of education is extremely important when a new technology is industrially implemented. Additive manufacturing and 3D printing offers freedom to design new products, production and generally ways of doing things. Development, planning and execution of education for additive manufacturing and 3D printing is challenging as this area develops very fast. New innovations are coming almost every month. Planning of education for additive manufacturing and 3D printing requires collection pieces of data from various of sources. Additive manufacturing and 3D printing industry and its development has to be followed frequently, and material for additive manufacturing and 3D printing has to be renewed frequently.

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The thesis focuses on the water chemistry of the experimental test facilities and their reference VVER reactors. The main objective of the thesis is to provide recommendations for water chemistry management for laboratory facilities (VEERA, PACTEL) simulating the VVERs and for the large future facilities of the Lappeenranta University of Technology. In the beginning, the concept of nuclear power generation and the applicability of the nuclear power usage is discussed. Next, different water chemistry and water purification systems in primary and secondary circuits currently used at the power plant have been outlined. Also the construction geometry and design of test facilities PACTEL and VEERA, as well as the operation principles of their main equipment has been described. Finally, the appropriate water chemistry and water treatment system have been proposed for the existing and future experimental facilities of LUT.

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Yli puolet kuntien vuosibudjeteista kuluu sosiaali- ja terveyspalveluihin. Jatkossa väestö ikääntyy ja huoltosuhteen muutos tulee niukentamaan kuntien resursseja ja lisäämään palvelujen tarvetta. Näin ollen vaikuttavien ja kustannustehokkaiden ratkaisumallien luominen on ensiarvoisen tärkeää. Tutkimuksen tavoitteena on rakentaa malli, jota voidaan hyödyntää tuottavuuden, vaikuttavuuden ja kustannusvaikuttavuuden jatkuvassa seurannassa alueellisissa sosiaali- ja terveyspalveluissa ja testata mallia esimerkkitapauksilla. Pääpaino on vaikuttavuudessa ja kustannusvaikuttavuudessa. Aiemman tutkimuksen perusteella tuottavuuden, vaikuttavuuden ja kustannusvaikuttavuuden mittaamiseen on useita lähestymistapoja. Tässä tutkimuksessa tuottavuutta arvioidaan panosten ja tuotosten suhteella, vaikuttavuutta palvelujen käytöllä ja kustannusvaikuttavuutta palvelujen käytön kustannuksilla. Kirjallisuudesta nousee esille selkeä tarve yli perinteisten organisaatiorajojen menevälle jatkuvalle vaikuttavuuden seurannalle. Aikaisempi tutkimus kattaa kertaluontoisia selvityksiä, joissa usein mittarit ovat operatiivisella tasolla, toimialasidonnaisia tai vaikeasti mitattavissa. Tutkimus on suunnittelutiedettä. Tutkimuksen lopputuloksena syntyy sosiaali- ja terveyspalvelujen käyttömalli (sote-palvelujen käyttömalli), jota varten toteutetaan tietokanta ja raportointikerros. Sote-palvelujen käyttömallia testataan tässä tutkimuksessa kolmella eri organisaatioyksiköllä ja asiakasryhmällä, jotka ovat strategisesti merkittäviä tutkittavalle organisaatiolle ja asiakasryhmiin on kohdennettu selkeä kehittämistoimenpide (kuntoutukseen panostaminen ja vammaisten sekä vanhusten laitoshoidon purku). Sote-palvelujen käyttömalli tuottaa tietoa kehittämistoimenpiteiden tuottavuudesta, vaikuttavuudesta ja kustannusvaikuttavuudesta. Sote-palvelujen käyttömallin todetaan soveltuvan tutkittavaan organisaatioon ja sote-palvelujen käyttömalli on sielläjatkuvassa käytössä. Sote-palvelujen käyttömalli on siirrettävissä myös muihin soteorganisaatioihin ja laajennettavissa myös muihin sosiaali- ja terveyspalveluihin ja niitä lähellä oleviin palveluihin.

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Tässä työssä esitellään yleisesti ORC-prosessi, sen toimintaperiaate ja käyttökohteet. Työn tavoitteena oli todentaa diesel-moottorin savukaasujen lämpöenergian sähköenergiaksi muuntavan mikro-ORC-energianmuuntimen suorituskyky. Suorituskyky pyrittiin toteamaan laskemalla laboratoriomittauksista saadusta datasta koelaitoksen sähköntuotannon hyötysuhde ja vertaamalla sitä mallinnuksessa laskettuun hyötysuhteeseen. Esitys käytännöstä suorituskyvyn todentamiseen kuuluu työn sisältöön. Koelaitoksen suorituskykyä ei pystytty toteamaan turbogeneraattoriin liittyvien ongelmien vuoksi. Tarkasteltavaksi tähän työhön jäi koelaitoksen suorituskykyyn olennaisesti liittyvien laitoskomponenttien toiminta niille tyypillisten mittausdatasta laskettujen tunnuslukujen kautta. Koelaitoksella käytettyjen lämmönsiirrinten todettiin olevan kykeneviä siirtämään tarpeeksi lämpöenergiaa 130 kW jarruteholla toimivan diesel-moottorin savukaasujen lämmöstä sähköenergian tuotantoon. Laitoksen kaupallistamista tarkasteltiin asiakkaan ja valmistajan näkökulmasta. Tarkasteluun sisältyi katsaus kaupalliseen versioon kuuluvista ominaisuuksista, alihankinnasta ja säädöksistä, jotka laitoksen on täytettävä markkinoille päästäkseen.

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The importance of industrial maintenance has been emphasized during the last decades; it is no longer a mere cost item, but one of the mainstays of business. Market conditions have worsened lately, investments in production assets have decreased, and at the same time competition has changed from taking place between companies to competition between networks. Companies have focused on their core functions and outsourced support services, like maintenance, above all to decrease costs. This new phenomenon has led to increasing formation of business networks. As a result, a growing need for new kinds of tools for managing these networks effectively has arisen. Maintenance costs are usually a notable part of the life-cycle costs of an item, and it is important to be able to plan the future maintenance operations for the strategic period of the company or for the whole life-cycle period of the item. This thesis introduces an itemlevel life-cycle model (LCM) for industrial maintenance networks. The term item is used as a common definition for a part, a component, a piece of equipment etc. The constructed LCM is a working tool for a maintenance network (consisting of customer companies that buy maintenance services and various supplier companies). Each network member is able to input their own cost and profit data related to the maintenance services of one item. As a result, the model calculates the net present values of maintenance costs and profits and presents them from the points of view of all the network members. The thesis indicates that previous LCMs for calculating maintenance costs have often been very case-specific, suitable only for the item in question, and they have also been constructed for the needs of a single company, without the network perspective. The developed LCM is a proper tool for the decision making of maintenance services in the network environment; it enables analysing the past and making scenarios for the future, and offers choices between alternative maintenance operations. The LCM is also suitable for small companies in building active networks to offer outsourcing services for large companies. The research introduces also a five-step constructing process for designing a life-cycle costing model in the network environment. This five-step designing process defines model components and structure throughout the iteration and exploitation of user feedback. The same method can be followed to develop other models. The thesis contributes to the literature of value and value elements of maintenance services. It examines the value of maintenance services from the perspective of different maintenance network members and presents established value element lists for the customer and the service provider. These value element lists enable making value visible in the maintenance operations of a networked business. The LCM added with value thinking promotes the notion of maintenance from a “cost maker” towards a “value creator”.

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This thesis develops a method for identifying students struggling in their mathematical studies at an early stage. It helps in directing support to students needing and benefiting from it the most. Thus, frustration felt by weaker students may decrease and therefore, hopefully, also drop outs of potential engineering students. The research concentrates on a combination of personality and intelligence aspects. Personality aspects gave information on conation and motivation for learning. This part was studied from the perspective of motivation and self-regulation. Intelligence aspects gave information on declarative and procedural knowledge: what had been taught and what was actually mastered. Students answered surveys on motivation and self-regulation in 2010 and 2011. Based on their answers, background information, results in the proficiency test, and grades in the first mathematics course, profiles describing the students were formed. In the following years, the profiles were updated with new information obtained each year. The profiles used to identify struggling students combine personality (motivation, selfregulation, and self-efficacy) and intelligence (declarative and procedural knowledge) aspects at the beginning of their studies. Identifying students in need of extra support is a good start, but methods for providing support must be found. This thesis also studies how this support could be taken into account in course arrangements. The methods used include, for example, languaging and scaffolding, and continuous feedback. The analysis revealed that allocating resources based on the predicted progress does not increase costs or lower the results of better students. Instead, it will help weaker students obtain passing grades.

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The context of financial services has been characterised by changes in the regulatory, technological and societal landscape. Consumers are increasingly interested in mobile payments, crowdfunding and microfinance services, either for themselves or because collaborative consumption is viewed as a more sustainable. Retail branches are re-organised to further meet the expectations of customers, start-ups focusing on technology for financial services (i.e. Fintech) are ever growing and financial services companies reinforce their own innovation practices (e.g. creation of innovation labs or venture capital investment funds). The innovation ecosystem around financial services companies represents the many actors with whom they can co-create and co-produce innovative new services for their customers (or for themselves). The innovation process is no longer a closed internal effort but needs to include external actors from the innovation ecosystem. This topic is especially interesting in a small and open economy where the financial centre takes a prominent place in the economy. The research question is therefore “How does the innovation ecosystem influence the innovation process within financial services companies?”. The influence of the innovation ecosystem on the innovation process within financial service companies mainly comes from its social capital and value creation efforts. However learning to work and exchange in an innovation ecosystem is also expected to influence the innovation process in place. Realizing the potential of the innovation ecosystem requires sufficient capabilities to manage new information coming from the innovation ecosystem. The professional associations provide the necessary coordination among actors in the innovation ecosystem to co-create and appropriate value, while fostering co-evolution within the innovation ecosystem.