Lisensiaatintyöt

Recent Submissions

  • Gilmore, Clifford (Helsingin yliopisto, 2014)
    Linear dynamics is a rapidly evolving area of operator theory, however the only results related to the dynamics of the commutator operators have hitherto been on the characterisation of the hypercyclicity of the left and right multiplication operators. This text introduces the requisite background theory of hypercyclicity before surveying the hypercyclicity of the left and right multiplication operators. It expands on this to prove sufficient conditions for the hypercyclicity of the two-sided multiplication operator. Conditions are established under which the general class of elementary operators are never hypercyclic on Banach algebras and notably it is shown that elementary operators are never hypercyclic on the space of bounded linear operators of the Argyros-Haydon Banach space. In the first main result of this text, large classes of operators for which the induced commutator operators are never hypercyclic on separable Banach ideals are identified. In particular it is proven that commutator operators induced by compact and Riesz operators are never hypercyclic on the ideal of compact operators and that commutator operators are also never hypercyclic on the ideal of compact operators of the Argyros-Haydon Banach space. In the Hilbert space setting it is demonstrated that commutator operators induced by hyponormal operators are never hypercyclic on the ideal of Hilbert-Schmidt operators. In the second main result, nonzero scalar multiples of the backward shift operator on the Hilbert space H is identified as a strong candidate to induce a hypercyclic commutator operator on the separable ideal of compact operators on the separable Hilbert space H. However it is proven that it cannot have a dense orbit and hence is never hypercyclic. This study indicates that the commutator operator typically behaves in a non-hypercyclic fashion and that if they exist, instances of hypercyclic commutator operators are rare.
  • Raisio, Juha (Helsingin yliopisto, 2016)
    The phenology and flowering of the pedunculate oak (Quercus robur L.) in Southern Finland was monitored during 1999-2006, in the Framnäs and Lenholm oak forests, which are mixed with hazels, birches, aspens, rowans, lindens, junipers, spruces, pines. Both stands are about 20 ha and located by the northern limit of natural distribution of oaks. The distance between the groves is about 60 km. A long-term pasture of about 150 years, on both islands has reduced the oak stands, however in recent decades selective cuttings have been made to help the oaks. In the south-western coastal areas degree days ranged from 1405,7 to 1737,7 d.d. in 1999-2006, indicating higher cumulating heat sums than on average over the normal period for the years 1981-2000. A total of 20 oaks × 3 branches /each tree sits in both stands, which equals 120 branches that were surveyed. The cork oak flowering model was modified to common oaks. Phases: 0-7 in male flowering were specified: from the dormant period (0) to swelling of the buds, from the onset of flowering to withering of the inflorescences (6). During the female flowering similar phases were found - from the rest period of apex buds (0) to the development of auxiliary buds on same year shoots. Further from the onset of first tiny female flowers to the withering of stigmas on the latest ones (6). The common oak flowering model was accurate enough and easy to apply in the survey. Male flowering began in 1999-2006 between 17th May and 6th June. Anthesis followed a few days later, when most of the staminate inflorescences had ripened. The catkins in the full length turned from green to bright yellow just before pollen release. Ripening was equal to phase 5 in the model of staminate flowering. Onset of the first female flowers began when the phase for stamens was about 3-4. Pollen receptivity of the first glossy reddish stigmas began when male flowering was about 5-5,5. The peak for female flowering took place a few days later than the anthesis, indicating protandry in common oak flowering. The period from pollination to fertilization is still a competition sequence for the pollen tubes. The stigmas, the developing female flower organs in gynoecium and the pollen tube cell tissue interact at the cell level. The self-incompatibility system acts on preventing selfing. Hence the loss of female flowers is huge, in some trees and in some years about 50% of the flowers fall down by the time of fertilization. Only 0-7,5% of the female flowers of the peak blossom period developed into acorns, which was less than in many other investigations. The suitable period for the common oak reproduction is very limited in the northernmost parts of its natural distribution. If the onset of the male flowering was delayed to early June, the number of female flowers was consequently low (years 1999, 2003, 2005). The detected linear regression is a topic for further studies. It remains unclear in this current scrutiny how the regulatory process acts on limiting the seed set and preventing extra ecological costs of any failing reproduction. In 2004-2006 a new potential pest, the black-dotted groundling, Stenolechia gemmella L. attacked the common oaks in many parts of Southern Finland. The moth larvae hollowed out new, same year shoots by length of few centimeters. Slightly afterwards shoots with their leaves and flowers turned brown. In July 2005 hundreds of withering shoots appeared in large oak crowns and of the monitored 1500 shoots in Framnäs 249 were infested by the moth larvae. Larvae and pupae are present in shoots in July, the adults emerge later in August or September.
  • Lipponen, Suvi (2015)
    Hevosen hankositeen yläkiinnityskohdan vamma (proximal suspensory desmitis= PSD) takajalassa on tärkeä aihe, koska usein vamma on krooninen, helposti uusiutuva ja vaikeasti hoidettava. Se esiintyy usein urheiluhevosilla, joiden nopea paraneminen takaisin käyttökuntoon on tärkeää omistajille. Nykykäsityksen mukaan vamman aikainen diagnosointi on tärkeää. Täten hoidoilla saadaan parempia tuloksia. Diagnosointi on haastavaa. Täten tulee käyttää mieluiten useita eri kuvantamismenetelmiä ontumatutkimuksen ja puudutusten lisäksi, jotta päästäisiin mahdollisimman tarkkaan diagnoosiin. Kuvausmenetelmistä suositellaan käytettäväksi ainakin röntgen- ja ultraäänitutkimusta. Vamman parantamiseen on kokeiltu useita erilaisia hoitomuotoja, joista parhaat tulokset on tällä hetkellä saata syvän metatarsaalisen faskian faskiotomialla ja lateraalisen plantaarihermon syvän haaran neurektomialla. Muita vähemmän invasiivisia hoitomuotoja ovat paineaaltohoito ja uusimpana regeneratiiviset hoitomuodot. Vamman diagnosointi tänä päivänä on helpompaa, kun on saatavilla erilaisia kuvantamismenetelmiä ja paranemisennuste on parantunut huomattavasti verrattuna konservatiivihoitoon, jolla vammaa aiemmin hoidettiin. Työ on ajankohtainen, suomenkielinen katsaus takajalan hankositeen yläkiinnityskohdasta saatavilla olevaan tutkimustietoon. Asiasta kiinnostuneet voivat helposti perehtyä aiheeseen tämän tekstin avulla suomeksi.
  • Karlia-Palomäki, Christina (Helsingin yliopisto, 2016)
    The framework of this research is competition law and IPRs. Competition law regulation concerning Block Exemption concerning the Transfer of Technology (TTBER) of the Treaty on the Functioning of the European Union (TFEU) Articles 101 and 102 mean that companies have to take into consideration certain regulation in order to avoid the intervention of competition authorities. As the system of TTBER is based on a self-announcement system, companies may take more or less risk in their agreement praxis. The research questions were: What are the preconditions for a competition according to the new Block Exemption Regulation concerning the Transfer of Technology (TTBER)? This research question can be divided into the following sub-questions: 1) How small and medium size companies (SMEs) fulfill the criteria of permitted competition after the changes in Block Exemption Regulation concerning the Transfer of Technology? – how SMEs try to achieve market shares 2) How small and medium size companies fulfill the criteria of Block Exemption according the new regulation? These questions were scrutinized by litterature reviews, case analysis and updated materials from experts e.g. corporate lawyers and attorneys. The main results of the research were as follows: The doctrine of the misuse of a dominant position has often been a core issue in case law of European Court of Justice (ECJ) and especially the essential facilities problem. It has a chain effect to TTBER regulation. A dominant company can decide how to promote innovations. To identify the market shares it is important to find the relevant markets. The strength and knowledge of the licensee effects to the possibilities to succeed in license negotiations. A powerful company having the resources can take into account the TTBER regulation to favour its goals and take advantage of the economic condition. Often a high royalty is agreed in order to avoid claims. In R&D projects the amount of innovations is relevant in contract negotiations. In some cases companies have agreed of royalties in relation to the amount of the IPRs. SMEs grow into large companies and form joint ventures: it is not easy to evaluate how and when they fulfil the conditions of permitted competition. Technology pools are nowadays allowed, if they are not aiming to restrict competition and there are grounds for them, which are related to the technology. The arrangement is accepted, when it brings benefits to consumers.
  • Salo (os. Muurinen), Kirsti (Helsingin yliopisto, 2016)
    The history of Finnish school system has mutual interest with agricultural club established in USA in the beginning of 1900. Learning by doing was the motto for 4H-work and experiential learning was valued at school as well. The Evergreen Model of Environmental Education action plan describes the use of the outdoors as an expanded learning environment and to develop sustainability education at modern school. The model was initiated by a local 4H-association in collaboration with the local municipality and the schools. The intention according to the schools curricula and learning goals was to fulfill experiential learning out of doors and to realize a holistic vision of a sustainable learning environment. The development of the model started in 2003 with four pilot schools and by 2010 all 16 primary schools of the municipality were involved - from small village schools (32 96 students, grades 1 6) to large comprehensive schools (370 583 students, grades 1 9). Within seven years school gardens were built, active learning in nearby farms was conducted, and learning sessions were organized in the nearby forests and in special nature resorts. Research questions were: What were the reasons to start the collaboration to develop new methods and places for learning outdoors? How did the teachers experience garden activities and learning outdoors? What were hindrances and promoting factors for learning outdoors and gardening in school every day? The Evergreen Model of Environmental Education has shown positive results and could be at least partly applied in all schools. Action plans need to be developed depending on each school s own possibilities and surroundings. Schools possess limited resources and teachers need to feel starting a program and teaching outdoors is easy. Collaboration with specialists like farmers or gardeners is important while establishing outdoor education in addition to everyday school work. The size of a school was not a hindrance for outdoor learning but larger groups did require extra adults and more complex organizing efforts to have successful sessions.
  • Ritschkoff, Anne-Christine (1992)