A modified nominal stress method for fatigue assessment of steel plates with thermally cut edges

Thermal cutting methods, are commonly used in the manufacture of metal parts. Thermal cutting processes separate materials by using heat. The process can be done with or without a stream of cutting oxygen. Common processes are Oxygen, plasma and laser cutting. It depends on the application and material which cutting method is used. Numerically-controlled thermal cutting is a cost-effective way of prefabricating components. One design aim is to minimize the number of work steps in order to increase competitiveness. This has resulted in the holes and openings in plate parts manufactured today being made using thermal cutting methods. This is a problem from the fatigue life perspective because there is local detail in the as-welded state that causes a rise in stress in a local area of the plate. In a case where the static utilization of a net section is full used, the calculated linear local stresses and stress ranges are often over 2 times the material yield strength. The shakedown criteria are exceeded. Fatigue life assessment of flame-cut details is commonly based on the nominal stress method. For welded details, design standards and instructions provide more accurate and flexible methods, e.g. a hot-spot method, but these methods are not universally applied to flame cut edges. Some of the fatigue tests of flame cut edges in the laboratory indicated that fatigue life estimations based on the standard nominal stress method can give quite a conservative fatigue life estimate in cases where a high notch factor was present. This is an undesirable phenomenon and it limits the potential for minimizing structure size and total costs. A new calculation method is introduced to improve the accuracy of the theoretical fatigue life prediction method of a flame cut edge with a high stress concentration factor. Simple equations were derived by using laboratory fatigue test results, which are published in this work. The proposed method is called the modified FAT method (FATmod). The method takes into account the residual stress state, surface quality, material strength class and true stress ratio in the critical place.

Political Legitimacy and Ethnocultural Justice. Essays on Public Reason, Democratic Citizenship, and the Rights of Cultural Minorities

In this thesis, I argue that there are public cultural reasons that can underpin public justifications of minority rights of indigenous and national minorities in a constitutionaldemocracy. I do so by tackling diverse issues facing a liberal theory of multiculturalism. In the first essay, I criticize Will Kymlicka’s comprehensive liberal theory of minority rights and propose a political liberal alternative. The main problem of Will Kymlicka’s theory is that it builds on the contestable liberal value of individual autonomy and thus fails to take diversity seriously. In the second essay, I elaborate on the Rawlsian political liberalism assumed here by criticizing Chandran Kukathas’s version of political liberalism as overly accommodating to diversity. In the third essay, I discuss questions of method that arise for a political liberal approach to the moral-political foundations of multiculturalism, and propose a certain understanding of the political liberal enterprise and its crucial standard of reasonableness. In the fourth essay, I dwell on the political liberal ethic of citizenship and propose a strongly inclusionist interpretation of the duty of civility. In the fifth and last essay, I introduce a certain understanding of ethnocultural justice and propose a view on certain cultural reasons as public cultural reasons. Cultural reasons are public when they are based on necessarily established cultural marks of a democratic polity, as specified by the cultural establishment view; and when they are crucial for the societal cultural bases of self-respect of citizens. The arguments in this thesis support, and help to spell out, moral-political rights of indigenous and national minorities as formulated in international legal documents, such as the Declaration on the Rights of Indigenous Peoples (United Nations 2007) or the International Covenant on Economic, Social and Cultural Rights (United Nations 1966).

Derivative hedging strategies for bitumen price risk

The objective of the study is to extend the existing hedging literature of the commodity price risks by investigating what kind of hedging strategies can be used in companies using bitumen as raw material in their production. Five different alternative swap hedging strategies in bitumen markets are empirically tested. Strategies tested are full hedge strategy, simple, conservative, and aggressive term structure strategies, and implied volatility strategy. The effectiveness of the alternative strategies is measured by excess returns compared to no hedge strategy. In addition, the downside risk of each strategy is measured with target absolute semi-deviation. Results indicate that any of the tested strategies does not outperform the no hedge strategy in terms of excess returns in all maturities. The best-performing aggressive term structure strategy succeeds to create positive excess returns only in short maturities. However, risk seems to increase hand-in-hand with the excess returns so that the best-performing strategies get the highest risk metrics as well. This implicates that the company willing to gain from favorable price movements must be ready to bear a greater risk. Thus, no superior hedging strategy over the others is found.

Le relazioni Italo - Finlandesi nella documentazione del Ministero degli Affari Esteri italiano e nel "Memoriale" di Attilio Tamaro (1929-1935)

My doctoral thesis may be placed within the branch of studies on the history of international relations and it examines the development of Italian-Finnish bilateral relations during the mandate of Attilio Tamaro, the plenipotentiary Minister (1929-1935). The research is based exclusively on Italian sources, on the private documentation of the diplomat and on his “Memoriale”, which have been critically analysed, using theories, such as those on the policies of power, on the soft power and on foreign trade. This research aims to draw attention to the bilateral dynamics, and to bridge the gaps of the specific historiography, paying attention to the relations between the Lapua movement and Italian fascism, and to the role that the Minister Tamaro played. The 1929-1935 period is the most intense one in the bilateral relations, and it expands those already begun in the Twenties, thereby replacing the idea of a poor and backward Italy with that of a modern, strong and orderly country that fascism had been capable of building. The need for Finland to solve its internal problems led to the development of the lappist movement in the first few months of 1930 which, with its anticommunism and anti-parliamentarism, led conservative Finland to look towards the Italian political model with particular fondness. The Italian diplomacy, at least during the Grandi ministry, distinguished itself for its moderate involvement in its connections with lappism. After 1932, with the spread of universal fascism, opposing national-socialism, the relationships between fascism and the lappist movement intensified and led the IKL (Patriotic People’s Movement) into the Italian sphere. Actually, especially after 1933, what was the most effective instrument of Tamaro’s political action was culture: the Italian Readership, the cultural associations, and the use of the cinematic arts and art were the channels for the expansion of a cultural imperialism which abounded in political propaganda. With the War of Ethiopia in 1935, the good Italian-Finnish relationships partly cooled down because Italy appeared to be a dangerous nation for the stability of the security system of Finland. The research results are stimulating: they bring to light the ambitions of great power of monarchist-fascist Italy; they show the importance of the Italian example in inspiring the conservative Finnish right-wing; they allow one to hypothesize that there was at least an indirect influence of the Italian model on the development of Finnish events. The aspiration of our research is to stimulate further studies on diplomatic, military and trade relations between Italy and the Scandinavian countries from 1919 to today.

Käyttöpääoman hallinta ja taloudellinen suorituskyky valmistavissa teollisuuden alan yrityksissä talouden laskusuhdanteen aikana

Tämän Pro gradu – tutkielman aiheena on tutkia kahden valmistavan teollisuudenalan käyttöpääomassa ja käyttöpääoman hallinnassa tapahtuneita muutoksia talouden laskusuhdanteen aikana vuosina 2007–2013. Käyttöpääoman kuuluvien varojen ja velkojen perusteella tutkimuksessa selvitetään, ovatko yritykset toteuttaneet aggressiivista, kohtalaista vai konservatiivista käyttöpääoman hallintastrategiaa ja kuinka käyttöpääoman hallinta on muuttunut laskusuhdanteen aikana. Käyttöpääoman hallinnassa tapahtuneita muutoksia verrataan toimialojen kannattavuudessa ja maksuvalmiudessa tapahtuneisiin muutoksiin. Tutkimus on rajattu koskemaan metsä- ja metalliteollisuuden keskisuuria yrityksiä. Tutkimusaineisto kerättiin Voitto + -tietokannasta satunnaisotannalla. Yrityksien valintakriteerinä käytettiin 10 - 50 miljoonan euron vuosiliikevaihdon väliä, jonka tuli täyttyä yritysten osalta vuonna 2007. Tutkimusotokseen valittiin molemmilta toimialoilta yhteensä 31 yrityksen tilinpäätösaineistoja vuosilta 2007 –2013. Tutkimuksen perusteella sekä metsä- että metalliteollisuuden yritysten käyttöpääoman on lisääntynyt laskusuhdanteen aikana. Käyttöpääoman hallinta on molemmilla toimialoilla muuttunut konservatiivisemmaksi, myyntisaamisten ja vaihto-omaisuuden lisääntymisen ja ostovelkojen vähenemisen seurauksena. Käyttöpääoman kasvu kuitenkin paransi toimialojen maksuvalmiutta. Toimialojen kannattavuus heikkeni laskusuhdanteen aikana, johtuen heikentyneestä liikevaihdosta. Metalliteollisuuden toimialalla käyttöpääomaprosentti kasvoi ajanjaksolla kannattavuuden heikentyessä, johon vaikutti liikevaihdon lasku ajanjaksolla. Metsäteollisuuden alalla käyttöpääomaprosentti seurasi kannattavuuden muutoksia, ja kääntyi viimeisinä vuosina laskuun liikevaihdon kasvun seurauksena.

Työkoneen levypyörän kantavuus

Työkoneen vanteen kantavuuslaskentaan käytettävän taulukon epäiltiin tuottavan todellista huonompia kantavuuksia etenkin suurten offset-arvon vanteiden tapauksessa. Tutkimuksessa yhdestä tyypillistä kokoa edustavasta vannetyypistä valmistettiin offset-säädettävä erikoisvanne. Vanteen käytön aikaisia rasituksia seurattiin venymäliuska-antureilla koeajoradalla tavanomaisissa ajotilanteissa eri offset-arvoilla traktorilla vedettävän kuormitetun testivaunun avulla. Saatuja tuloksia vertailtiin vanteen elementtimallin tuloksiin ja käytettyjä kuormitusolettamia muutettiin. Tutkimuksen tuloksena kantavuuden laskentaan käytettävän taulukon todettiin toimivan pääosin mittauksen mukaisesti. Vanteen offset-arvolla on laskentataulukon mukaisesti merkittävä vaikutus vanteen keskiön väsymiskestävyyteen. Suurilla negatiivisilla offset-arvoilla vanteen kestoiän määrä ajo taisella alustalla, kun taas suurten positiivisten vanteiden väsymisvaurio aiheutuu pääosin kaltevalla pinnalla ajosta. Mittauksella pystyttiin osoittamaan laskentataulukon konservatiivinen olettama etenkin suurten negatiivisten offset-arvojen vanteille, jolla kyseenomaisten vanteiden väsymiskestoikää voidaan parantaa merkittävästi. Lisäksi laskentaohjelman tekemisessä käytettyjen kuormitus- ja reunaehto-olettamien vahvistettiin toimivan keskiön kannalta riittävällä tarkkuudella. Havainnolla on tärkeä rooli tulevissa elementtimenetelmään perustuvissa kantavuuslaskelmissa.