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  • Kurkela, Janita (2015)
    Monsuuni-ilmastoa luonnehtivat vuodenaikojen mukaan suuntaansa vaihtavat ilmamassojen liikkeet sekä niihin liittyvät sadekaudet. Aasian monsuunisysteemi on yksi maapallon merkittävimmistä ilmastosysteemeistä ja sen vaikutusalue ulottuu Arabian meren länsiosista Itä-Aasiaan sekä Australian pohjoisosiin. Se jaetaan kahteen ala-systeemiin: Intian monsuuniin ja Itä-Aasian monsuuniin. Monsuunialueella asuu yli puolet maapallon ihmisistä ja näiden yhteiskuntien hyvinvointi on täysin riippuvainen kesämonsuuni sateiden maantieteellisestä jakautumisesta sekä voimakkuudesta. On esitetty, että käynnissä oleva ilmastonmuutos on jo vaikuttanut monsuunisysteemeihin. Tässä tutkimuksessa perehdyin holoseenin aikaisiin monsuunivaihteluihin. Omia tuloksiani vertasin muualta monsuuni alueelta peräisin oleviin monsuuni-ilmastoa käsitteleviin tuloksiin sekä myös Pohjois-Atlantin alueen ilmastorekonstruktioihin. Tutkimuskohteeni on Kumphawapi järvi, joka sijaitsee Koillis-Thaimaassa. Thaimaa on ihanteellinen kohde monsuunitutkimuksille, koska se sijaitsee molempien monsuunin ala-systeemien vaikutusalueella. Järven syvimmästä kohdasta noudettiin 3.81 metriä pitkä sedimenttisarja, josta määritin orgaanisen aineksen määrän sekä analysoin kasvimakrofossiili koostumuksen. Sedimenttisarja ajoitettiin radiohiili menetelmällä suhteellisen tiheällä näytevälillä ja ajoitusten perusteella luotiin ikä-syvyys malli. Tätä aineistoa käytin menneiden vedenpintojen vaihteluiden eli holoseenin aikaisen monsuunin voimakkuuden rekonstruoimiseen. Laskin näytteistä myös makroskooppiset hiilipartikkelit. Näiden avulla arvioin ihmistoiminnan mahdollista vaikutusta ympäristöön. Omaa aineistoani tukemaan minulla oli käytettävissäni aiempaa paleoekologista aineistoa samasta järvestä. Tutkimustulokseni paljastivat, että järven hydrologiset olosuhteet olivat holoseenin aikana vaihdelleet huomattavasti. Holoseenin alussa järvi oli suhteellisen syvä, ja tämä viittaa kosteisiin olosuhteisiin eli voimakkaaseen kesämonsuuniin. Keski holoseenin aikana veden syvyys oli matala, joka taas viittaa heikkoon kesämonsuuniin. Myöhäisholoseenin aikana veden syvyys vaihteli. Tämä viittaa monsuuni-ilmastossa tapahtuneisiin lyhyempikestoisiin vaihteluihin. Omat tulokseni vertautuvat hyvin muihin ilmasto rekonstruktioihin Aasiasta. Kumphawapi-järven aineisto myös viittaa siihen, että alueellinen monsuuni-ilmasto on ollut yhteydessä pohjoisten leveysasteiden ilmastoon. Lisäksi Aasian monsuuni-ilmasto näyttäisi kytkeytyvän trooppiseen nk. ENSO systeemiin. Kumphawapi-järven sedimentaatiossa esiintyi usean tuhannen vuoden katkos, joka ajoittuu keski holoseeniin, Siksi tulkinta siitä oliko keski holoseenin veden pinnan lasku ilmaston vai ihmisen aiheuttama, jää tässä tutkimuksessa selvittämättä. Joka tapauksessa aineistoni viittaa siihen, että myöhäisholoseenin vaihtelut veden pinnoissa oli ilmaston eikä ihmistoiminnan aiheuttamaa. Kasvimakrofossiilimenetelmä yhdistettynä hyvään kronologiaan ja litologiseen analyysiin, muulla paleoekologisella aineistolla tuettuna, osoittautui hyväksi tavaksi tutkia holoseenin aikaisia kosteusolosuhteita. Eri tutkimusten tulkintojen välillä esiintyi kuitenkin epäyhtenäisyyttä ja siksi lisätutkimukset ovat tarpeellisia; ja näissä tutkimuksissa kannattaa hyödyntää myös kasvimakrofossiili menetelmää.
  • Suonperä, Enni (2016)
    In 2011 AA Sakatti Mining Oy published a promising ore discovery in Sodankylä, Finnish Lapland. The need for more knowledge led to the start of Sakatti geoenvironments -project in collaboration with the University of Helsinki. As a part of this project, the Holocene paleohydrology of Viiankiaapa mire was reconstructed. Viiankiaapa mire is located on the eastern side of Kitinen River and has developed in close connection to it. It is a large aapamire complex consisting of multiple smaller minerotrophic mire sites and bogs. Viiankiaapa conservation area was first established in 1988. A large portion of Viiankiaapa is now part of the Natura 2000 conservation network. To study the development and paleohydrology of Viiankiaapa mire, a 4.3 meter peat core (VA310315, 7497803 N/0490511 E) was collected using a Russian peat sampler. From the peat core, six specimens from increasing depth levels were sampled for age determinations to establish reliable chronology. Dating was conducted at LUOMUS Laboratory of chronology at the University of Helsinki, using 14C AMS dating method. Peat stratigraphy was studied on site and humification determined using von Post method. Physical properties of the peat (LOI550 and water content) were determined in 2 cm resolution. The colour of the ash was determined using Munsell soil color chart. Same resolution was used in geochemical analyses of 17 individual elements (C, N, S, P, K, Ca, Mg, Na, Fe, Al, Cu, Ni, Zn, Ti, Mn, Pb, Si). C, N, and S contents were determined using gas chromatography, while all the other elements were analyzed using ICP-MS. From the element contents, multiple ratios were calculated in order to study the Holocene deposition pattern of individual elements. Element/Ti profiles show an increase in mineral material input in c. 8 000 – 6 000 cal. BP, c. 4 800 – 3 000 cal. BP, and 2 500 – 1 900 cal. BP, suggesting enhanced flooding of Kitinen and increased humidity. Early Holocene (11 700 – 8 200 cal. BP) is indicated as a period of higher detritic material input. Waterlogged conditions, however, have most likely not been continuous during early Holocene. This is suggested by the occurrence of dark red color of iron oxide (FeO) in the ash. The occurrence of iron sulphides (possibly pyrite, FeS2) in the ash of the bottom section of the core suggests that waterlogged conditions were reached during Mid -Holocene. The 8.2k event is showcased in the profiles of multiple elements, including the main nutrients (C, N, P). These elements show significant increase after the cold event. Ca/Mg, Ca/K, and Mg/K ratios were used to estimate the trophic state of the mire and the sources of the mineral material. Also the accumulation of Pb was studied more closely. All of these factors suggest that atmospheric input and groundwater alone could not have transported the entire volume of the mineral material, and therefore river Kitinen may be considered as the main water and nutrient source until the damming of the river in 1984 and 1995.
  • Seppälä, Ulpu (2017)
    To date, Turkey has one of the highest refugee populations in the world. The Syrian conflict has played a major role in this as over 2,5 million Syrians have taken refuge in Turkey. Most of Syrian refugees are residing in the largest city of Turkey, Istanbul. Turkey is a signatory member of the Convention relating to the Status of Refugees, however has an exception for permanent residency granted only for European refugees. Thus, under Turkish refugee policy, Syrians are merely granted temporary protection that guarantees them a temporary residency permit. However, the policy does not cover; at the time of this research; the right to work. Syrian refugees, undocumented Syrians and Syrian Palestinians are especially vulnerable in Turkish society due to the lack of permanent residency and legal work. This research identifies how Syrian refugees create home as well as the factors that influence their home-making process in Istanbul. The factors are evaluated through the conditions under which Syrian refugees are residing in Istanbul including the right to work, housing and residency. The research also evaluates the refugees home-making in retrospective to their living conditions, feeling of home, legal position, access to a dwelling place as well as cultural identification. Although, this research focuses on the individual experience of home-making for Syrian refugees, it considers and examines Syrian refugees in a context of politicised bodies. As international refugees, Syrian refugees are highly politicized bodies, whose lives are affected by international politics as well as the domopolitics of the country in which they reside. Subsequently, their home and their home-making processes are also politicised. Beyond politics, refugeeness alters one's relationship to home and place, making home a complex concept attached with emotions and potential pain and loss. Literacy identifies that refugees displace their home through space and time. Hence, this research treats home as a socially and culturally produced metaphor that describes a person's belonging within socio-spatial narratives, but of which content is individually chosen to describe or to support a person's identity and psychological environment. The method of this research was a combination of two field trips to Istanbul, Turkey, fourteen in-depth interviews and qualitative analysis. The main reference of the research are the fourteen in-depth interviews that included ten men and four women; aged from 20 to 40 years old; Syrians residing in Istanbul. The interviewees were selected through social media online connections and face-to-face acquaintances during the field trips. The interviewees time of residence in Istanbul varied from two months to over four years. The eleven influencing factors identified in this research can be more commonly divided into two categories: the common factors and the personal factors. Common factors related to the responder's habitation environment; such as the city of Istanbul and the Turkish society. These common factors included: the city itself, the Turkish culture and society, the legislation, working life, housing, discrimination and relationships with their family and friends as well as with the Turkish people. The interviewees considered these factors as the ones that impacted everyday life and which they could not 'escape'. Personal factors that were identified are related to interviewees personality, world views and emotions. The interviewees could be divided into four main categories of personal factor denominators: their relationship to Syria, sense of belonging, definition of home and views of the future. This research concludes that displacement has an impact on how home is perceived and reflected by the interviewees. Its findings are in accordance to previous research literature on home-making among refugees, but it questions refugee policies that emphasis on repatriation as the most favourable long term solution for refugees as well as the position of housing as a most influential factor in refugees' home-making, by stating that other factors such as relationship to family and friends and earning a living, are higher in importance for those who have arrived into a new country less than two years ago.
  • Eronen, Aleksi (2014)
    Global energy consumption is rising day by day. One answer for the increased energy demand is photocatalytic water splitting for hydrogen production. In water splitting solar energy is stored to chemical bonds between oxygen and hydrogen molecules. Stored energy can be released by burning hydrogen in presence of oxygen. The literature review of this thesis briefly discusses heterogeneous semiconductors. The main focus of the work has been on homogeneous catalysis. Data describing their catalytic properties in oxygen production was gathered for such transition metals as Ru, Co, Ir, Fe and Mn. In the section dealing with hydrogen production, main focus has been on transition metals such as Co, Fe and Ni. The aim of the study was to produce homogeneous catalyst for water splitting which can do both gases simultaneously. So far the literature has only reported catalysts which require three-component system (catalyst + photosensitizer + sacrificial reagent) and that produce only either of the gases (hydrogen or oxygen). The idea behind the work was to combine oxygen producing catalyst and hydrogen producing catalyst to one system where transition metal complexes act both as electron acceptors and donors. Thus, the sacrificial reagent is not needed. In the experimental part of the work, combination of hydrogen forming Co-catalyst (S 12) and oxygen forming Ru-catalyst (ORu 5) with Ru-photosensitizer (PS 1) was able to split water photocatalytically in the absence of sacrificial reagents. Recorded turnover numbers were low (about 1 for oxygen and 2 for hydrogen) because of the fast deactivation of catalytic species. The deactivation is likely caused by direct electron interaction between Co-catalyst and Ru-catalyst.
  • Virtanen, Lotta (2014)
    Hopea on kiiltävä metalli, jota käytetään paljon koruissa, aterimissa ja erilaisissa elektroniikan laitteissa. Hopea reagoi helposti ilmassa olevien rikkiyhdisteiden kanssa, mistä johtuu hopeaesineiden tummuminen ajan kuluessa. Hopean pääkorroosiotuote on hopeasulfidi, mutta myös hopeakloridi on yleinen varsinkin meri-ilmastossa. Tummumisen estämiseksi hopeaa on seostettu muilla alkuaineilla. Korroosionkestävistä metalliseoksista tutkituimpia ovat hopean ja palladiumin seokset, joita on käytetty erityisesti hammaslääketieteessä. Hopea voidaan myös suojata erilaisilla pinnoitteilla, jotka estävät hopean reaktion eri yhdisteiden kanssa. Hopean suojaamiseksi on käytetty perinteisesti orgaanisia lakkoja, kuten selluloosanitraattia. Hopeaa on pinnoitettu myös muilla orgaanisilla pinnoitteilla, kuten polymeereillä ja tioleilla. Tiolit muodostavat itsejärjestyviä monokerroksia hopean pinnalle. Näiden kalvojen suoja perustuu vahvaan Ag-S-sidokseen ja pitkään hydrofobiseen hiilivetyketjuun. Hopeaa on pinnoitettu myös ohuilla metallioksidi- tai nitridikalvoilla. Metallipinnan esikäsittelyn on havaittu parantavan kalvojen passivoitumisominaisuuksia. Tutkielman kirjallisessa osuudessa käsitellään hopean tummumiseen vaikuttavia tekijöitä sekä esitellään hopean passivoinnissa käytettyjä menetelmiä. Kokeellisessa osuudessa tutkitaan hopean passivointia näkymättömillä ALD-menetelmällä valmistetuilla pinnoitteilla. Höyrystetyille hopeapeileille kasvatettiin ALD-menetelmällä erilaisia pinnoitteita alumiinioksidista, tantaalioksidista ja titaanioksidista. Pinnoitetuille hopeapeileille tehtiin EN ISO 4538-standardin mukainen tioasetamidikorroosiokoe, jossa hopeat altistuivat rikkivedylle. Hopeapeilit valokuvattiin ja niiden heijastus mitattiin ennen altistusta ja säännöllisin aikavälein altistuskokeen aikana. Paras suoja saavutettiin alumiinioksidin ja tantaalioksidin nanolaminaattirakenteisella pinnoitteella, jonka paksuus oli noin 60 nm.
  • Paananen, Kaisa (2013)
    The focus of this study is locations of hotels. Location has a huge meaning in hotel business. In urban tourism, researching the location is logical, because hotels are tourism elements that are only used almost entirely by tourists. The area research in the thesis is the capital region of Finland. The research is carried out by using the principles of inductive research, The method used are GIS analyses and interviews. With the help of GIS analyses, the location is studied by using a typology of hotels in a tourist city developed by researchers Ashworth & Tunbridge. In this typology, hotels are divided under six locations: hotels in traditional market/city gate, near railway station, main access roads, in nice and practical locations, in transition zones of CDB and the historic city and in urban periphery. Data is also analyzed with models of urban structure and Leisure product model. Themes are formed based on start-up year, size, level of chains and quality. Interviews will give more information about the background of the locations and the influences of planning. SeutuCD10 is used as a data. In additional data has been collected manually. As in the typology, also in the capital region of Finland the development of vechicles has had a major impact in the hotel sector. There are clusters of hotels near railway stations, and these areas have been popular locations for hotels from early days of railway. There is a cluster of hotels near the airport, and in that area there is also a postmodern entertainment center. The biggest difference compared to typology is that in the capital region, there are not any hotels in the traditional market locations nowadays. There are also hotels in the capital region that are difficult to categorize using this model for example hotels away from city center, near some elements of nature and hotels near harbors. Based on results, the hotels in the capital region of Finland are divided in nine different categories. Four of these are not mentioned in typology. These are hotels away from city center, hotels in trendy areas in the outskirts of city center, hotels in CBD and hotels near passenger harbors.
  • Psyrillou, Anna Magdalini (2024)
    Although hot particles can be released to the environment via many pathways (nuclear accidents, warfare, industry), the understanding of their behavior in the human body, as well as their consequent health impacts. This study aims to understand how uranium particles (UO2 particles) and particles derived from nuclear accidents (Cesium-rich Micro-Particles, CsMPs) behave chemically after inhalation and how they impact human lungs. Specifically, the study aims to ascertain the duration of particle persistence within tissues post-inhalation, investigate the likelihood of translocation or chemical modifications, and evaluate both the chemical and possible radiobiological risks posed to organisms. To achieve this objective, the physicochemical alterations of UO2 particles and CsMPs after exposure to simulated lung fluids and their resulting cytotoxicity in cell models are studied. Dissolution studies are conducted, first using simulated lung fluid (SLF), that represents the interstitial lung fluid in the lung alveolar, followed by artificial lysosomal fluid (ALF), which mimics the conditions particles encounter after internalization by alveolar macrophages. Particle solubility is assessed using chemical analytical techniques (ICP-MS). Thus, the potential dissolution of these particles or their ability to persist as intact point sources of radiation over extended periods is explored. Particles after dissolution are examined using SEM-EDX analysis to study changes in the surface morphology and chemical composition. Additionally, the initial uptake and cytotoxic effects of these particles is investigated using murine lung fibroblast and macrophage cell lines, aiming to establish a detailed understanding of their radio- and chemical toxicity. UO2 particles presented minimal dissolution in SLF(< 2% of U dissolved) during 60 days of dissolution and a formation of a secondary phase on the surface of the particle was observed (mineral of uranyl associated with phosphates, most likely autunite). After exposure to ALF for 30 days, UO2 particles dissolved extensively ( ̴ 90% of U dissolved). From the single-particle dissolution for the CsMPs generated from the Fukushima-Daiichi accident, preliminary data has shown that within 30 days, a range of 10-25% of Cs-137 was leached into the SLF solution. Modified UO2 (after dissolution in SLF for 10 days, 180 days or ALF for 30 days) shown similar cell cytotoxicity profile as unmodified UO2 particles (20-40% cell viability after 24 hours).
  • Zschauer, Karoliina (Helsingin yliopistoHelsingfors universitetUniversity of Helsinki, 2012)
    This study focuses on households energy consumption in the Taita Hills of South-East Kenya, especially on the use of fuelwood. The wood use habits are approached through the local women and families who represent the grass root level actors. The Taita Hills are known for their rich biodiversity. Areas of indigenous mountain rainforests play a crucial role as the water towers as well as being home for many indigenous plants and animals. However, the high population pressure, lack of cultivated land, poverty and different socio-political factors has led to a degradation and loss of biodiversity. The main energy source of households in the Taita Hills is still firewood, the use of which has effects on the environment as well as on people s health and time management. This vulnerability caused by biofuels is examined in two case study areas. Both of these areas are located near an indigenous forest boarder but are situated on different agro-ecological zones. The present methods and circumstances of collecting firewood are also compared to the situation 30 years ago, when the legislation allowed more extensive use of forest resources. This research is a qualitative study. The primary data was gathered during two field trips in the Taita Hills, in 2009 and 2010, by using interviews and various participatory methods. All together 50 households as well as different district authorities, non- governmental organizations workers and private persons, were interviewed. The study concludes that the availability of firewood in The Taita Hills has diminished. People have to collect firewood from further away and from smaller areas. This has also increased the time used for collecting wood for fuel. Use of firewood increases households vulnerability by raising the work-load of women in particular, and also by its affect on the environment and health. In addition, this energy supply requires larger economical contributions, while people have to more often resort to purchasing. This weakens the economic situation of families and lessens their opportunities to plan their future or make other investments. Many people are not aware of the effects of the use of wood for fuel. For them it is difficult to understand that traditions passed down through many generations can have harmful consequences. Also poverty, lack of political interest and the lack of co-operation between local actors prevents implementation of new energy practices. Alternative methods should be introduced in order to change current unsustainable energy modes. However this should be done with respect and by taking into account the special features of the Taita Hills area.
  • Hyövälti, Maria (2016)
    In many Sub-Saharan countries, including Tanzania, people living in rural areas have difficult access to clean water and adequate sanitation. In these areas, traditionally women are responsible for the collecting of water and domestic activities, but at the same time they are not involved in the public decision making. Therefore, a focus on gender has become relevant in development aid practices, including project evaluation. Evaluation helps assessing relevance, efficiency, effectiveness, impact and sustainability of the implemented actions, compared with the proposed outcomes. Furthermore evaluation procedures of water and sanitation development projects should not ignore spatial factors, which are intertwined with societal factors in the operational environment of development projects. This requires acknowledging that interaction between gendered subjectivities and spatial and societal factors produces and reproduces gendered spaces. More particularly, this thesis considers a case study of a rural development project based in Kishapu District, northern Tanzania, implemented by Tanganyika Christian Refugee Service (TCRS). An evaluation framework is formed and used for unofficial evaluation of the project component in household water supply and sanitation. The framework has its emphasis in the beneficiaries of the development project and in gender equality, which are central for social sustainability. Emphasising social sustainability also furthers realisation of environmental sustainability. This research applies mixed methods, using both qualitative and quantitative analysis. The main data consists of semi structured stakeholder interviews, analysed using content analysis. The data includes also field observations, discussions, and GPS coordinated (geotagged) photographs of the main water sources. Development project documents are used as supporting material for the evaluation. An evaluative approach can be used as a scientific method in development geography, providing a critical viewpoint to the research and helping to connect research results with practical solutions. Evaluation shows the importance of exploring the views and knowledge of the beneficiaries. Through evaluation one can discover the positive effects, possible failures and possible future improvements and the sustainability of a development project. The household water and sanitation sector is a combined field revealing different gender needs that are rarely addressed in any development project, such as the use of toilets, or issues related to menstrual hygiene. There is a need to analyse how space is gendered and what kind of changes the development initiatives cause. For example, in the case study area of this thesis, there was clearly an attempt for public space to be more open to women, but the traditional division of public space being masculine and private space feminine was still dominant in practice. There is a need for change, because this division limits the participation of women and their ability to bring out their needs. The gendered division of space also limits the participation of men in training programs and activities relating to private space, which includes trainings related to household water, sanitation and hygiene.
  • Eskelä, Elina (Helsingin yliopistoHelsingfors universitetUniversity of Helsinki, 2009)
    The aim of this thesis is to examine the skilled migrants' satisfaction with the Helsinki Metropolitan Area. The examination is executed on three scales: housing, neighbourhoods and the city region. Specific focus is on the built environment and how it meets the needs of the migrants. The empirical data is formed of 25 semi-structured interviews with skilled migrants and additionally 5 expert interviews. Skilled and educated workforce is an increasingly important resource in the new economy, and cities are competing globally for talented workers. With aging population and a need to develop its innovational structure, the Helsinki Metropolitan Area needs migrant workforce. It has been stated that quality of place is a central factor for skilled migrants when choosing where to settle, and from this perspective their satisfaction with the region is significant. In housing, the skilled migrants found the price-quality ratio and the general sizes of apartments inadequate. The housing market is difficult for the migrants to approach, since they often do not speak Finnish and there are prejudices towards foreigners. The general quality of housing was rated well. On the neighbourhood level, the skilled migrants had settled in residential areas which are also preferred by the Finnish skilled workers. While the migrants showed suburban orientation in their settlement patterns, they were not concentrated in the suburban areas which host large shares of traditional immigrant groups. Migrants were usually satisfied with their neighbourhoods; however, part of the suburban dwellers were unsatisfied with the services and social life in their neighbourhoods. Considering the level of the city region, the most challenging feature for the skilled migrants was the social life. The migrants felt that the social environment is homogeneous and difficult to approach. The physical environment was generally rated well, the most appreciated features being public transportation, human scale of the Metropolitan Helsinki, cleanliness, and the urban nature. Urban culture and services were seen good for the city region's size, but lacking in international comparison.
  • von Kügelgen, Maria (2014)
    A significant number of people have problems with the batteries of their mobile devices. There are several energy saving applications available to tackle those problems. Most of them increase battery life mostly by automatically closing applications or operations. The user is for the most part unaware of what the energy saving application actually does. Therefore, even though the battery might last somewhat longer, the user may continue using behavioral patterns that drain the battery. There is little evidence to support the assumption that battery awareness applications lead to behavioral changes. Therefore, we decided to conduct a research on how a mobile awareness application called Carat is used, and how the behavior of its users changes over time. The study was carried out in two phases. In the first part of the study, we conducted a user survey, and studied the Carat log data of the devices represented in the survey. We found out that the behavior changes over time; there were significant differences between new Carat users, and the more experienced ones. The more experienced users had reduced their use of problematic applications more, were interested in different features of Carat, and opened it less often. In the second part of the study, we studied how new Carat users used Carat and what they thought of using it. They were interviewed twice, and they also wrote in a web diary about their experiences. We found out that the main difference in their thinking was the increase in overall awareness about applications as something that affects battery life. We also found out that inadequate, uninteresting and unclear information causes confusion and frustration, and decreases the likelihood of users sticking with Carat.
  • Maaranniitty, Saija (2020)
    Agile software development promotes self-organizing teams, close collaboration with client and team members, short iterative development cycles, response to changing requirements and continuous feedback. Originally agile methods were developed for small teams. As large organisations had a need for agile software development methods supporting several teams and collaboration between them, scaled agile development methods were developed. They promise increased productivity and quality, higher customer engagement and alignment between all levels of the enterprise. This thesis focuses on the software developers perceptions on team performance in Scaled Agile environment. More specifically this thesis studies how team performance is perceived to be impacted in organization that has adopted Scaled Agile Framework (SAFE). The study was designed to acquire descriptive knowledge through empirical studies. This thesis is based on an investigation of a single case company based in Finland. The data for analysis was collected from semi-structured interviews with 5 experienced developers. The findings show that several factors impact software developers team performance experience. By investigating the point of view of practitioners, we observed that team performance is a concept that evolves over time and is prone to be influenced by surrounding environment. This understanding can be used to adjust software development method related practices and organizational factors. This study provides pieces of advice on what kind of practices support or hamper team performance and how to improve them.
  • Liu, Jian (2014)
    Online social networks have brought along much convenience to our daily lives. On the other hand, they also provide platforms for the rapid propagation of unsafe content. Providing easy-to-use ways for ordinary users to avoid unsafe content online is an open issue. In this thesis, we mainly study two schemes that are based on social navigation to identify unsafe content. The first one is crowdsourcing, which has two main drawbacks: (a) a time lag before unsafe content is flagged as such, and (b) the difficulty of dealing with subjective perceptions of 'inappropriateness''. We propose a machine learning approach to address the time lag problem and get a promising result. This approach could be used to complement crowdsourcing. We also study the notion of 'groupsourcing'': taking advantage of information from people in a user's social circles about potentially unsafe content. Groupsourcing can both address the time lag problem and identify inappropriate content. To test its effectiveness, we have implemented FAR, which allows savvy Facebook users to warn their friends about potentially unsafe content, and conducted a controlled laboratory study. The results show that groupsourced signals can complement other types of signals and compensate for their weaknesses by countering viral spreading of unsafe content in a more timely fashion. The current version of FAR, consisting of a Facebook application and a Firefox browser extension is publicly available for use.
  • Nyström, Henrietta (2023)
    Urbanization, densification of the built environment, community degradation, and privatization and commercialization of space have shaped the urban development of Helsinki and also worldwide. These environmental, social, and economic problems have increased political pressure to find appropriate uses for existing spaces. The development of urban commons, i.e. shared, often non-commercialized spaces in urban environments, has entered the policy arena in recent years. This master's thesis examines how the ideas underlying urban commons are intertwined with contemporary neoliberal urban policy and planning. The ideas underlying urban commons include notions of social processes and socio-spatial relations that allow us to reimagine urban space and to figure out in what ways and by whom it is owned, managed, and utilized. The study aims to find out how the interrelationships between urban commons and neoliberalism are manifested in urban space and in the objectives behind the creation of urban commons. I approached the topic from the perspective of public administration and therefore examined in more detail two projects/actions managed by public sector organizations in Helsinki: Circular Green Blocks and Enhancement of the Sharing Economy in Zoning Plans. Data was collected through seven semi-structured interviews with planning and policy professionals and from several planning documents. Discourse analysis was used as a method of analysis and enabled the discovery of the meanings and representations of the world that underlie talk about urban commons. The results of this study show that the development of urban commons is intertwined in complex ways with neoliberalism in urban politics, which became evident through five discourses uncovered. The discourses of welfare and the right to the city revealed attempts to create a more spatially and socioeconomically equal as well as open urban space. Creating space that supports sustainable economic development was another key objective manifested in the discourse on the green economy. The support for the private sector in policymaking revealed an entrepreneurial discourse that indicated that urban space was sometimes treated as a commodity. A managerial discourse revealed a shift in urban governance and the role of the public sector, which showed that urban space was also sometimes treated as something non-political. The study concludes that the development of urban commons is influenced by neoliberal ideals, but also by ideas that can be considered as going beyond neoliberal ideology. For example, ideas of equality and welfare that reflect the tradition of welfare state policies in Finnish politics. The study encourages further research on the governance of urban commons, power relations in policymaking, and discourses among other actors in planning.
  • Palsamäki, Christian (2015)
    Steam power revolutionized shipping in the beginning of the 19th century. At the local level, the new technology enabled faster water transport connections operated by predetermined time schedules and routes. The aim of this Master's thesis is to provide an overview of the beginning, development and end of the local steamboat traffic in Helsinki. The industrial breakthrough, which started during the second half of the 19th century, was followed by a rapid population growth and urbanization process which shaped the city and society in many different ways. The development of the steamboat traffic is viewed as part of this urbanization process. In the actual study section of the thesis, I have examined the settlement development along the steamboat networks from the 1890s to the 1930s. The subject of the study can be classified as historical geography, transport geography and urban geography. The study is descriptive. A model designating the relationship between urban transport systems and the spatial form and organization of the city is adopted as the theoretical framework of the study. The research material consists of literature, historical maps and timetables. Maps produced based on historical spatial information illustrates the changes in the urban structure of the city. The study shows that local steamboats primarily served as a transportation mode related to different leisure activities for the urban residents. The regular water transport connections created conditions for the expansion of the summer villa settlement and later the steamboats also maintained transportation to a number of people`s parks established in the1920s and 1930s. Local steamboat transportation networks, along with other urban transportation modes contributed to the urban development and expansion of Helsinki, though their role has been marginal compared to other modes of transport. Still today, many of the villas built in the turn of the 19th and the 20th centuries are part of the maritime landscape of Helsinki. Several of the remaining villa areas are classified as nationally significant built cultural environment, which therefore also affects the land use in the future. Many of the people`s parks established in the early 20th century are still in recreational use. The transportation connections to the recreational islands is today maintained by motorized water-buses. Steamboat traffic has thus, at least indirectly, affected the landscape of the coastal areas and islands of the Helsinki archipelago.
  • Gasques Rocha Pinheiro, Beatriz (2020)
    Geometric isomers are of extreme importance due to the different properties of E and Z compounds. The interconversion between these forms allow to explore a vast amount of applications since their use in perfume and food industry until the development of photoactive drugs and advanced polymers. Included in this scenario are the E/Z isomers of pepper alkaloids, whose broad range of desirable pharmacological activities, such as anti-inflammatory, antioxidant and anti-cancer effects, makes them a focus in multidisciplinary research. Black pepper contains several of these alkaloids, among which piperine is the most abundant. Its properties have been studied for many years, with highlight for its pungency and flavour, in addition to medicinal applications that date from the development of ancient Indian and Chinese medicine. Piperine and structure-related compounds undergo rapid double bond isomerization in the presence of light, equilibrating to a mixture of four geometrical isomers, due to the two conjugated double bonds present in their structures. The biological activity of these isomers differs from those of the natural abundant E/E molecules. Thus, emphasizing the importance of having reliable analytical assays for their separation, detection and quantification. The current project pursued the development of a robust HPLC assays for isomers separation for piperine and some analogues. The effort included the extraction of piperine from black pepper and its use for the synthesis of highly pure piperylin and piperlonguminine standards. Piperine extraction kinetics was also studied to optimize the extraction procedure. The standards of alkaloids were isomerized using sunlight and then HPLC separation methods on chiral stationary phases were successfully established to resolve their E/Z isomers. Isocratic runs were also developed for piperine, piperylin and piperlonguminine, with the goal of adapting these methods to LC/MS application in the future. These last separations could be accomplished within 25 minutes with critical resolutions values larger than 1.8.
  • Seppänen, Kaapo (2021)
    We determine the leading thermal contributions to various self-energies in finite-temperature and -density quantum chromodynamics (QCD). The so-called hard thermal loop (HTL) self-energies are calculated for the quark and gluon fields at one-loop order and for the photon field at two-loop order using the real-time formulation of thermal field theory. In-medium screening effects arising at long wavelengths necessitate the reorganization of perturbative series of thermodynamic quantities. Our results may be directly applied in a reorganization called the HTL resummation, which applies an effective theory for the long-wavelength modes in the medium. The photonic result provides a partial next-to-leading order correction to the current leading-order result and can be later extended to pure QCD with the techniques we develop. The thesis is organized as follows. First, by considering a complex scalar field, we review the main aspects of the equilibrium real-time formalism to build a solid foundation for our thermal field theoretic calculations. Then, these concepts are generalized to QCD, and the properties of the QCD self-energies are thoroughly studied. We discuss the long-wavelength collective behavior of thermal QCD and introduce the HTL theory, outlining also the main motivations for our calculations. The explicit computations of self-energies are presented in extensive detail to highlight the computational techniques we employ.
  • Mielonen, Mika (2013)
    Mobiililaitteiden suosion kasvun myötä Web ja erilaiset sovellukset ovat yhä tärkeämpi osa ihmisten jokapäiväistä elämää. Samalla verkkosivujen ja sovellusten suunnittelulta ja toteutukselta edellytetään yhä monipuolisemmaksi kasvavan laitekannan huomioimista, sillä informaation odotetaan olevan saavutettavissa laitteesta riippumatta. Jatkuvasti kehittyvät avoimet Web-tekniikat ja niiden keskiössä oleva HTML5 voidaan yleisesti nähdä kustannustehokkaana ratkaisuna eri näyttökokojen ja sovellusalustojen kattamiseen, koska yhteisenä tekijänä eri laitteissa on selain. Erilaisten Web-sovellusten yleistyessä niiden toteutukset pohjaavat yhä enemmän sovelluslogiikan siirtämiseen palvelimelta selaimeen, ja yksisivuinen sovellusmalli (SPA-malli) on muodostumassa merkittäväksi. Tässä pro gradu –tutkielmassa tarkastellaan HTML5:n nykytilaa ja tulevaisuuden mahdollisuuksia erityisesti Web-sovelluksille hyödyllisten piirteiden ja sovellusliittymien kautta, kun vertailukohtana ovat alustakohtaiset (iOS, Android jne.) tekniikat. Tutkielman empiriaosassa näkökulmaa tarkennetaan laajan laitekannan tuen mahdollistaviin HTML5:n osiin, SPA-malliin, sekä sovellusarkkitehtuurin erityispiirteisiin, joihin perehdytään SAK:n responsiivisen verkkosivuston, sekä sen taustajärjestelmän tarjoaman esimerkin avulla. Johtopäätöksinä todetaan, että avoimien Web-tekniikoiden tarjoamat edut tulevat jatkossa yhä korostumaan alustakohtaisiin tekniikoihin nähden. SPA-mallin huomattiin parantavan käyttökokemusta tavallisiin verkkosivustoihin verrattuna, vaikka tarkastelun kohteessa mallia ei hyödynnetty parhaalla mahdollisella tavalla. Laajalle laitekannalle suunnatun toteutuksen todettiin edellyttävän huomiota latausaikoihin, käyttökokemukseen, laitetukeen ja sovellusarkkitehtuuriin, jonka sopivana lähtökohtana voidaan pitää Web-käyttöön suunniteltuja MVC-sovelluskehyksiä niiden tarjoaman selkeän rakenteen ansiosta, sekä JavaScriptin käyttöä taustajärjestelmästä alkaen erityisesti esimerkin kaltaisilla sisältörikkailla verkkosivustoilla. Mobiilioptimointi todettiin hyödylliseksi ja mahdolliseksi toteuttaa ilman erityistä sovelluksen kompleksisuuden lisääntymistä.
  • Polus, Aku (2021)
    We begin by discussing the essential concepts within the standard cosmology where the dark matter is "cold" and collisionless. We consider the structure formation in the dark matter component and present problems faced by the standard cosmology as well as some prospects for the solutions to those. The main problem considered in this work is the tension in the value of the Hubble constant measured with different procedures. We present the theories behind the procedures, and conclude the study of the tension by considering the most notable interpretations for the reason behind it. We then set up a proposal for an alternative model describing the dark sector. It is a hidden copy of the visible sector electromagnetism, allowing for a radiative cooling in virializing structures. By assuming first an asymmetric particle content, we study which scales of the dark matter halos are eligible to collapse into dense structure. Acquiring a mass function then allows to conclude how much from the total dark matter component is expected to collapse. If instead the dark matter particle content is taken to be symmetric, the collapsed fraction is assumed to annihilate into dark radiation. With certain modifications to the freely available Boltzmann code CAMB, we construct to the code a representation of the cosmology defined by our model. Lastly we use the modified cosmology to create a fit to the data defining the Hubble constant, and see for the relief of the tension. We find that our model provides a reasonable history for the energy content of the universe, and a notable relief to the Hubble tension, although the improvement is only a minor one compared to some more modest modifications to the cosmology.
  • Airola, Taru (2017)
    Tiimityöskentely ja voimavarojen yhdistäminen ovat olennainen osa nykyaikaista ohjelmistokehitystä. Viime vuosien ohjelmistoyritysten menestystarinoiden takana on usein joukko ihmisiä, jotka yhdessä muodostavat huipputuottavan ohjelmistotiimin (high-performing software team). Huipputuottavat ohjelmistotiimit ovat tiimejä, jotka suoriutuvat tehtävistään merkittävästi keskivertotiimiä paremmin. Huipputuottaviin tiimeihin kuuluvilla henkilöillä on oikeat taidot, tavoitteet ja asenteet tehtävien suorittamiseksi. He ovat erityisen sitoutuneita työhönsä, sekä toisiinsa. Tiimin tuottavuutta voidaan arvioida esimerkiksi tarkastelemalla tuotteen myyntiä tai arvioimalla tuotteen laatuominaisuuksia. Huipputuottavan ohjelmistotiimin rekrytoiminen saattaa olla hankalaa, sillä mikään ennalta määritelty toimi ei näytä takaavan huipputuottavan tiimin muodostumista, koska siihen vaikuttavat useat eri muuttujat. Rekrytoinnissa voi kuitenkin pyrkiä etsimään oman yrityksen kulttuuriin sopivaa ja tietotaidoiltaan oikeanlaista henkilöä. Ennen rekrytointia on hyvä selvittää, minkälaista henkilöä ja osaamista yritykseen tarvitaan. Rekrytointiin voi käyttää useita erilaisia keinoja. Yksi vaihtoehto on etsiä sopivaa henkilöä oman yrityksen sisältä, tai kysyä suosituksia nykyisiltä työntekijöiltä. Lisäksi sosiaalinen media on jatkuvasti kasvava rekrytointikanava varsinkin nuorempien henkilöiden keskuudessa. Osana tutkielmaa haastateltiin kuuden suomalaisen ohjelmistoyrityksen edustajia yritysten rekrytointitapojen selvittämiseksi. Haastatteluissa nousi esiin, että yritysten mielestä rekrytoinnissa oli tärkeää haettavan henkilön sopivuus yrityksen kulttuuriin, mihin liittyy esimerkiksi henkilöiden asenteet, arvot ja sosiaaliset taidot. Yrityksissä arvostettiin oma-aloitteisuutta, itsensä kehittämistä ja konsulttimaisuutta. Lisäksi tekniset taidot olivat tärkeä arvioitava asia. Kaikkien yritysten rekrytointiprosessiin kuului ainakin yleinen haastattelu ja tekninen haastattelu. Henkilöiden osaamista ja asenteita arvioitiin erilaisten haastattelujen avulla, joista osassa haastateltavalle annettiin ratkaistavaksi teknisiä tehtäviä. Haastattelujen perusteella omien työntekijöiden suositukset olivat tärkein lähde hyvien työntekijöiden löytämiseen. Myös sosiaalinen media ja perinteiset työpaikkailmoitukset olivat tärkeä osa rekrytointiprosessia.