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One significant contemporary change is the disappearance of the industry from the downtown areas and now also from suburbs. By moving further away from the city centers, the industry freed and is still freeing valuable land that has lately been harnessed to whole new purposes. The industrial district of Pitäjänmäki is now experiencing the second wave of the industrial movement. The industry has once moved away from the center to new and more spacious areas and now it is moving away also from the suburbs. The aim of the study is to find answers to the next two questions: What is the reason for the areal changes of use in the former industrial areas? How well is the industrial area of Pitäjänmäki suitable for housing? Methods of the study are literature review and passive observation in the study area. There is no single term for the areal change of use but many related terms can be found. Regarding the terms the study concentrates on the gentrification, the zone of transition of the concentric zone model of Burgess, the urban fallows and the restructuration. In the observation part the areal change of use is seen concretely in the areal changes from industry to housing. Strömberg living area and Kutomotie area were chosen as subjects of the observation study. In addition two residential areas next to the industrial area, Talinlehto and Pajamäki, were observed in order to find the differences between the residential area built in the industrial area and the more ordinary residential area. There are two things, that support each other, that have an effect on the areal changes of use in the former industrial areas. After moving further away from the city centers the industry has left behind unoccupied usable buildings. It has required a prolonged battle for conservation in order to save the industrial buildings. The change of the general planning ideology to the direction of valuing the old structures has been significant. On the other hand the desire of individualism in housing and the change of housing preferences have been equally important. The so called creative class living in the cities has been in the vanguard of the progress. The suitability of the industrial area of Pitäjänmäki as an housing area was studied by observing the chosen residential areas. According to the points given in the observation the result was bipartite amongst the residential areas situated inside the industrial area. Kutomotie area, the recent area of change, is clearly the weakest of the study areas. The lack of space is the main weakness of the area and it is caused by the trend of preserving and reusing the industrial buildings which prevents the major changes in the area. On the other hand the success of the Strömberg residential area compared to the similar residential area of Talinlehto shows that it is possible to build normal blocks of flats in the industrial areas as functional wholes as long as the residential area and the surrounding streets are well planned.

The Helsinki region is growing, with processes of both centralisation and decentralisation characterising its development. Population growth, its distribution and ageing, the amount of jobs and their distribution on the regional level as well as climate change and developments in the economy on the global level induce challenges for urban planning. Planning should simultaneously be ecologically, socially and economically sustainable and promote regional competitiveness. Due to the complexity of this planning task and the recognition that the measures taken by different planning sectors affect each other and that their solutions are frequently common, it has been noted that the traditional sector-planning does not meet the requirements of achieving planning objectives effectively. Thus, new modes of planning, such as strategic planning and inter-administrative cooperation have been emphasised in literature. This view is central to the MAL cooperation as well. MAL cooperation consists of planning of land use (M), housing (A) and transport (L), which are integrated under one umbrella. This comprehensive approach to planning is thought to give the regions the most effective tools in improving prerequisites to the curbing of climate change, to securing of the functionality of people's everyday life and for development of the regions' competitiveness. The MAL cooperation in the Helsinki region has produced two letters of intent between the state and the municipalities (2008-2012 and 2012-2015). This study concerns itself with the current one (2012-2015), in which I focus on the intended development of the regional transport system. For the analysis, I also study three planning documents on transport and land use that form the background to the objectives and measures presented in the agreement. The documents are: National land use guidelines (2008), Transport policy report (2012) and Helsinki region transport system plan - HLJ 2011 (2011). At the heart of this study lies the assumption that, in the foresterian way, planning involves both technical uncertainty over knowledge and political ambiguity over means and ends. Together these two dimensions lead to the wicked problems of planning. In this research, I have approached the uncertainty/ambiguity dimensions from the perspectives of ecological, social and economical sustainable development and regional competitiveness. The assumption is that as these views are placed to overlap each other, differing ways of knowing and distinct interests promote contradictions and ambiguity and, thus, wicked problems. The study has been divided into four research questions: 1. How do the wicked problems take shape in developing of the regional transport system? 2. How are the wicked problems of the planning goals tried to be solved and what kind of challenges do these solutions include? 3. How are the solutions to the wicked problems legitimised in the planning documents? 4. What would be the answer of the agonistic planning to the question of managing the wicked problems? Based on the analysis, I propose that the wicked problems concentrate on the following themes: 1. Land use, especially commitment to the strategy of making the urban structure compact. 2. Financial challenges of the public sector, that is, who pays the bill of the targeted developments? 3. Improvement of the functionality of the transport system, especially what mode of transport (sustainable and equal transport or logistics and private cars) will be given the primary status. 4. Financial steering instruments (allocation, levels and means of taxes and subsidies). 5. The promotion of the new cooperative planning culture and how different ways of knowing, interests (ecological, social and economical) and working cultures could be reconciled in it? Finally, in order to manage the wicked problems, I suggest the agonistic planning as a possible method. The idea is, that within planning practices, conflict should be legitimised. But at the same time, it should be tried to be solved with other means than creating 'authoritative' consensus defined by the most powerful actors. I also suggest that with the agonistic pluralism, it would be possible to move from traditional 'either-or' planning solutions toward more democratic 'both-and' solutions.

Efficient service-oriented inter-enterprise collaboration focuses on the business processes of the enterprises and hides the technology differences between them. However, such collaboration induces two main challenges. First, there should be an accessible and functioning infrastructure available for the collaboration. Second, as the growing number of participants can lead to the growing level of misbehaving among them, and thus market deterioration, that is why the parties should have common understanding of the behavior that is appropriate and can be trusted. We focus on the trust relationships between the agents' interactions. Agents make a trust decision before interacting, and this decision among other factors is based on an estimation of another agent's reputation. A reputation management system collects and analyzes interactions experience between agents. Let us call a person, company or any other possible entity whose goal is to build an infrastructure for the interactions between enterprises using one of the trust and reputation management algorithms as an infrastructure builder. For an infrastructure builder it is important to evaluate and compare reputation management systems, choosing one of them based on the evaluation and comparison results. This remains an open question in research. The thesis aims at supporting the decision-making process of this kind. We suggest evaluation criteria for a trust or reputation management systems' evaluation. We implement a generic tool which can plug in a trust or reputation management algorithm and simulate the behavior of the multiagent system where every agent follows the same algorithm. We illustrate the tool's support for some of the suggested evaluation criteria. We provide some recommendations for further development of the generic tool for evaluating and comparing the above-mentioned behavior characteristics of different trust and reputation management algorithms. ACM Computing Classification System (CCS): Human-centered computing → Collaborative and social computing → Collaborative and social computing systems and tools → Reputation systems Computing methodologies → Artificial intelligence → Distributed artificial intelligence → Multi-agent systems

Latent semantic structure in a text collection is called a topic. In this thesis, we aim to visualize topics in the scientific literature and detect active or inactive research areas based on their lifetime. Topics were extracted from over 1 million abstracts from the arXiv.org database using Latent Dirichlet Allocation (LDA). Hellinger distance measures similarity between two topics. Topics are determined to be relevant if their pairwise distances are smaller than the threshold of Hellinger distance we set beforehand. The dynamic topic graph displays the evolution of topics over time. Topic hierarchical relationships are shown in a tree, where topics near the leaves are subtopics to those far from the bottom. The dynamic topic graph of category focuses on topics associated with a particular categories in the arXiv classification system. Logistic regression was used to predict topic lifetime and discover which factors have positive effect on lifetime and which ones induce the death of topics. Especially, we are interested in the effect of time, category, the number of documents, the number of topic variety and their interactions. In the experiment, we investigated topics in the dynamic topic graph of category under thresholds of Hellinger distance of 0.4, 0.5 and 0.6, respectively. Categories whose coefficients were negative for all datasets are defined to be popular as topics in this field are more probable to survive.

Arktis-alpiinisen kasvillisuuden taustalla vaikuttavat lukuisat ympäristötekijät, ja pienikin spatiaalinen tai temporaalinen muutos ympäristöoloissa voi vaikuttaa merkittävästi koko kasviyhteisöön. Tässä työssä tarkastelen, miten paikalliset ympäristömuuttujat topografia, maaperätekijät ja geomorfologinen häiriö vaikuttavat putkilokasvien lajirunsauteen paljakalla. Tutkin myös ovatko vaikutukset erilaisia toiminnallisten kasviryhmien välillä. Aineisto kerättiin kesällä 2011 Saanatunturin rinteeltä Kilpisjärveltä. Kasvilajistosta sekä erilaisista abioottisista ja bioottisista muuttujista kerättiin tietoa yhteensä 960 neliömetrin ruudulta, jotka sijaitsivat kuudella yhtenäisellä ruudukolla. Tutkimusasetelmassa minimoitiin alueellisten muuttujien vaihtelu ja maksimoitiin kasvipeitteen ja topografian paikallinen vaihtelu. Aineistoa analysoitiin monimuuttujamenetelmillä. Putkilokasveille ja niiden toiminnallisille ryhmille etsittiin hajonnan osituksella lajirunsauden alueellista vaihtelua parhaiten selittävät GLM ja GEE-mallit. Abioottisilla muuttujilla pystyttiin selittämään jopa 75 % lajirunsauden vaihtelusta tutkimusalueella, mikä osoittaa, että stressi on merkittävin paikallista lajirunsautta rajoittava ilmiö paljakalla. Myös tutkituilla häiriömuuttujilla on kasvillisuuteen stressivaikutuksia. Yksittäisistä muuttujista maankosteus selittää lajirunsautta ylivoimaisesti parhaiten, mutta myös muut maaperätekijät ovat tärkeitä. Maaperätekijät ovat vahvasti yhteydessä myös mesotopografiaan ja gemorfologiseen häiriöön, joiden itsenäiset merkitykset osoittautuivat pieniksi. Mesotopografia ja fluviaalinen häiriö olivat kuitenkin yksinään tärkeitä muuttujia kaikille lajirunsauksille. Lähes kaikki muuttujat ovat mukana parhaissa malleissa, eli myös yksinään vähäpätöisiltä vaikuttavat muuttujat ovat lajirunsaudelle merkityksellisiä, mutta niiden merkitys saattaa ilmetä vasta muiden muuttujien kautta. Tulos tukee aiempaa teoriaa siitä, että abioottisten muuttujien välillä vaikuttaa monimutkaisia vuorovaikutussuhteita. Eri toiminnalliset ryhmien lajirunsaudet reagoivat abioottisten muuttujien vaihteluun yllättävän samankaltaisesti. Suurimmat erot ilmenivät ruohojen ja ainavihantien varpujen välillä. Tulos johtuu ennenkaikkea ruohojen kapeasta sietoalueesta kosteus-, pH- ja lumenpaksuusgradienteilla, kun ainavihannat varvut taas sietävät paremmin kuivuutta ja hapanta maaperää, eivätkä ole tarkkoja lumenpaksuuden suhteen. Kaikki toiminnalliset ryhmät esiintyvät lähes koko tutkimusalueella rinnakkain, ja niiden väliset erot tulevat näkyviin vasta lajirunsauksien maksimeissa. Toiminnallisten ryhmien morfologisista ja fysiologisista eroista huolimatta ne ovat sopeutuneet ennenkaikkea paljakan karuihin ympäristöoloihin, mikä tekee niiden ympäristövasteista samankaltaisia.

Two different bio transfer standards (BTS), composed of fatty acid bilayers, NanoRuler and NanoStar were developed. NanoRuler consists of a nanometer scale staircase with eight steps that are 5 nm tall each and NanoStar is designed to have topological structure with sharp edge and three height planes 5 nm elevated with respect to each other. With NanoRuler nanometer vertical calibration from 5 nm to 40 nm is possible and NanoStar allows the evaluation of the instrument transfer function (ITF). Due to the soft nature of the standards, the topographical stability was researched. Thus, an investigation of the topographical stability of three NanoRulers and one NanoStar across 24 months was done by measuring the surface topography with a custom-built Scanning White Light Interferometer (SWLI). The BTS were measured over 100 times during the experiments and were stored in laboratory conditions. The step heights of the structures were calculated with a histogram method and the surface roughness of the samples was evaluated using the Sq parameter. The step height analysis method was compared to the standard method (ISO 5436-1) where applicable and no notable differences were found. In both roughness and step height data no linear or non-linear trends were found, and the step heights compared well with the literature values. For NanoRuler the step heights were 4.9 nm, 10.1 nm, 15.1 nm, 20.1 nm, 25 nm, 30.1 nm, 35.1 nm and 40.2 nm and the respective stabilities were 0.3 nm, 0.3 nm, 0.6 nm, 0.9 nm, 1.3 nm, 1.6 nm, 2.1 nm, and 2.5 nm. For NanoStar the step heights were -5.1 nm and 5.2 nm with stabilities 0.3 nm and 0.4 nm respectively. The NanoRuler had a surface roughness stability of 0.02 nm whereas NanoStar had a roughness stability of 0.01 nm. After 24 months both BTS types preserved their topographical structure and no issues with surface topographical stability were observed.

Fysikaalisten kenttien rakenteista solmittuja linkkejä ja solmuja on osoitettu esiintyvän useissa eri systeemeissä, optisista ja akustisista kentistä aina supranesteisiin. Tällaisten solmujen evoluutio ideaaleissa systeemeissä rajoittuu perinteisten solmujen, kuten kengännauhoista löytyvien, tyyppiseksi. Fysikaalisissa systeemeissä, joissa energiahäviöt ovat mahdollisia, mahdolliset evoluutiot ovat eksoottisempia; kentässä olevan solmun säikeet --- kentän topologisten pyörteiden ytimet --- voivat mahdollisesti kokea solmun topologiaa muuttavia evoluutioita ja purkautua erillisiksi solmuttomiksi silmukoiksi. Hyödyntämällä väritettyä linkkidiagrammiesitystä osoitamme yllä mainittuja evoluutioita välttävien topologisesti suojattujen pyörresolmujen olemassaolon spin-2 Bosen--Einsteinin kondensaatin syklisessä faasissa. Nämä ovat ensimmäiset suojatut pyörresolmut, jotka on löydetty fysikaalisesti toteutettavasta systeemistä. Todistuksessa käytetty väritysformalismi on yleinen viitekehys. Sitä voidaan soveltaa useisiin muihin systeemeihin, kunhan näiden järjestysparametriavaruuksien toinen homotopiaryhmä on triviaali. Syklisen faasin pyörresolmut ja -linkit mahdollistavat myös osittaisen luokittelun: jokainen solmu on ekvivalentti joukkoon irtonaisia apilasolmuja ja/tai kahdeksikkosolmuja, tai on triviaali. Kokonaislukuaskelin kvantittuneista pyörteistä muodostuvat linkit ovat ekvivalentteja joko Borromeon renkaisiin, suljettuun kolmen silmukan ketjuun tai triviaaliin silmukkaan.

There exists various suggestions for building a functional and a fault-tolerant large-scale quantum computer. Topological quantum computation is a more exotic suggestion, which makes use of the properties of quasiparticles manifest only in certain two-dimensional systems. These so called anyons exhibit topological degrees of freedom, which, in principle, can be used to execute quantum computation with intrinsic fault-tolerance. This feature is the main incentive to study topological quantum computation. The objective of this thesis is to provide an accessible introduction to the theory. In this thesis one has considered the theory of anyons arising in two-dimensional quantum mechanical systems, which are described by gauge theories based on so called quantum double symmetries. The quasiparticles are shown to exhibit interactions and carry quantum numbers, which are both of topological nature. Particularly, it is found that the addition of the quantum numbers is not unique, but that the fusion of the quasiparticles is described by a non-trivial fusion algebra. It is discussed how this property can be used to encode quantum information in a manner which is intrinsically protected from decoherence and how one could, in principle, perform quantum computation by braiding the quasiparticles. As an example of the presented general discussion, the particle spectrum and the fusion algebra of an anyon model based on the gauge group S_3 are explicitly derived. The fusion algebra is found to branch into multiple proper subalgebras and the simplest one of them is chosen as a model for an illustrative demonstration. The different steps of a topological quantum computation are outlined and the computational power of the model is assessed. It turns out that the chosen model is not universal for quantum computation. However, because the objective was a demonstration of the theory with explicit calculations, none of the other more complicated fusion subalgebras were considered. Studying their applicability for quantum computation could be a topic of further research.

Reshetnyakin lauseen mukaan kvasisäännöllinen kuvaus, joka ei ole vakio, on avoin, diskreetti ja suunnansäilyttävä. Suunnansäilyttävät kuvaukset määritellään topologisen asteen avulla ja siksi tässä tutkielmassa Reshetnyakin lauseen todistuksessa keskeistä on kvasisäännöllisen kuvauksen osoittaminen suunnansäilyttäväksi. Topologiselle asteelle on tässä tutkielmassa valittu analyyttinen lähestymistapa. Luvussa 3 topologinen aste määritellään jatkuvasti differentioituville funktioille ja luvussa 4 siirretään topologisen asteen määritelmä ja keskeiset tulokset Sobolev-funktioille. Reshetnyakin lauseen todistuksen runkona käytetään Titus–Youngin lausetta, jonka mukaan jatkuvat, kevyet ja suunnansäilyttävät kuvaukset ovat avoimia ja diskreettejä. Titus–Youngin lause esitellään ja todistetaan luvussa 5. Luvussa 6 esitellään kvasisäännölliset kuvaukset. Alaluvussa 6.1 tarkastellaan kvasisäännöllisten kuvausten ja elliptisten osittaisdifferentiaaliyhtälöiden yhteyttä. Osittaisdifferentiaaliyhtälöiden avulla voidaan osoittaa kvasisäännöllinen kuvaus kevyeksi. Viimeisessä luvussa esitellään Reshetnyakin lause ja osoitetaan, että kvasisäännöllinen kuvaus, joka ei ole vakio, on kevyt ja suunnansäilyttävä. Tällöin kvasisäännöllisen kuvauksen avoimuus ja diskreettisyys seuraa Titus–Youngin lauseesta.

Tosiaikainen tietovarasto on keskitetty tietokantajärjestelmä pehmeitä tosiaikaisia liiketoimintatiedon hallintasovelluksia varten. Näiden sovellusten perusvaatimuksena on tuoreen tiedon jatkuva saatavuus. Työssä käsitellään tosiaikaisen tietovaraston suunnittelua, tietovaraston jatkuvan ylläpidon eri vaiheita sekä näihin vaiheisiin soveltuvia menetelmiä. Tarkoitus on tuoda esiin kompromisseja, joita väistämättä joudutaan tekemään tietovaraston kyselytehokkuuden, viiveen ja jatkuvan saatavuuden välillä. Johtopäätöksenä suositellaan sitä suurempaa varovaisuutta mitä pienempiä viiveitä tavoitellaan. Liiketoimintatiedon hallintasovellusten tosiaikaisuus on ominaisuus, jota käyttäjät tavallisesti haluavat enemmän kuin tarvitsevat. Joissakin tapauksissa tosiaikaisuus on suorastaan haitallista. Mutta jos tosiaikainen tieto on välttämätöntä, samanaikaisia käyttäjiä on paljon, ja tarvittavat tiedot pitää yhdistää useasta lähdejärjestelmästä, niin tosiaikaiselle tietovarastoinnille ei ole kelvollista vaihtoehtoa. Tällöinkin riittää, että jatkuvasti ylläpidetään vain pientä osaa koko tietovarastosta.