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In this thesis I study the radiation balance and heat budget of a multiyear sea ice floe drifting in the central Arctic ocean. The objectives of the study were to quantify the vertical partitioning of shortwave- and longwave radiation and to quantify the different components of the heat budget of the floe in question, both inside and at its interfaces. The measurements were set up at 88 26.6N, 176 59.88W on 8th of August and carried out for ten days. The measurements were made as a part of the fourth Chinese National Arctic Expedition CHINARE2010. The measurement setup consisted of a net radiometer, four PAR-sensors, a pyrano-albedometer, three spectral radiometers, daily snow pit measurements, weather observations and six ice corings. With the data from these studies I was able to quantify the rate of melting and fluxes of heat both at the surface and at the bottom of the ice. The data allowed for examining the fraction of transmitted and conducted heat but were insufficient for properly quantifying the internal changes and spectral composition of the shortwave radiation at different depths. The surface was observed to be losing heat mainly in the longwave part of the spectrum. The average net radiation on top of the ice on wavelengths between 200 nanometers and 100 micrometers over the period was -25.0 Watts per square meter. The heat fluxes of the shortwave and longwave radiations were of opposite directions and the negative heat flux of the longwave radiation dominated until a distinct change in the radiative conditions on 17th of August. For the remainder of the period these heat fluxes nearly balanced each other and the average net radiation was -2.1 Watts per square meter. The latent and sensible heat fluxes were observed to have a minor role in the surface heat budget with averages of -1.5 Watts per square meter and -0.03 Watts per square meter respectively. The ice was observed to melt primarily at the bottom at a rate of 0.5 cm per day driven by the input of heat from the underlying ocean. Melting at the surface was not apparent until before the last two days of studies, when the upper layer of the snow cover melted. The changes in sea ice and snow cover were visually observed to exhibit significant spatial variability even on a single floe.

Active galactic nuclei (AGN) are one of the most powerful sources of the luminous Universe. Radio-loud AGN exhibit prominent relativistic outflows known as jets, whose synchrotron radiation can be detected in the radio domain. The launching, evolution and variable nature of these sources is still not fully understood. We study 3C 84, because its proximity, brightness and the intermittent nature of its jet makes it a good target to investigate these open questions of the AGN phenomena. 3C 84 (optical counterpart: NGC 1275) is a Fanaroff-Riley type I radio galaxy, located in the Perseus cluster at z = 0.0176. Due to its close proximity, 3C 84 has been a favourable target for observations throughout the entire electromagnetic spectrum, especially for ones in the radio domain. Its most recent activity started 2003, when a new component emerged from the core in the form of a restarted parsec-scale jet. This provided a rare opportunity to study the formation and evolution of a jet (see Nagai et al. 2010, 2014, 2017 and Suzuki et al. 2012). The highest resolution results were obtained by Giovannini et al. (2018), who imaged the source with the Global VLBI Network together with the Space Radio Telescope, RadioAstron. This enabled them to capture the limb-brightened structure of the restarted jet and measure its collimation profile from ~350 gravitational radii. In this work I present the 22 GHz RadioAstron observations carried out 3 years later, in a similar configuration, but with a significantly different sampling of the space baselines than the ones presented in Giovannini et al. (2018). The calibration was carried out in the Astronomical Image Processing System (AIPS), whereas imaging was done in Difmap (Shepherd 1997). The aim of this thesis work was to obtain a high-resolution image of the source, measure the collimation profile of the restarted jet, and compare the results with those of Giovannini et al. (2018) and verify the observed source structures and measured jet properties, if possible. Comparing the images of the two epochs (angular resolution of the 2016 observations is 0.217x0.072 mas at Pa=-49.6°), they both show a similar structure, with the radio core, a diffuse emission region (C2), and the hotspot (C3) at the end of the restarted jet. Edge-brightening is confirmed in the jet and the counter-jet. However, the jet has advanced ~1 mas, corresponding to the velocity of 0.55c. C3 has moved from the center of the feature to the jet head, indicating an interaction between the jet and the clumpy external medium (Kino et al. , 2018 and Nagai et al., 2017). The base of the jet has also changed between the observation, approximately by ~20°. In the light that in the 1990s the jet pointed towards C2, then swinged westwards when the jet emerged (Suzuki et al., 2012 and Giovannini et al., 2018), and on the 2016 image has moved towards its initial position. This suggest a precessing jet, observed and modeled by Dominik et al. (2021) and Britzen et al. (2019). Measuring the brightness temperature of the core and the hotspot shows a signifacant drop of 70% and 50% since the 2013 measurements, respectively, due to emission of jet material and the expansion of the jet. Jet width measurements between 1200 and 19000 gravitational radii reveal a less cylindrical collimation profile, with r ~ z0.31 – where z is the de-projected distance from the core and r is the width of the jet. The evolution of the restarted jet’s profile from quasi-cylindrical (Giovannini et al. 2018) to less cylindrical implies that the cocoon surrounding the jet (Savolainen, 2018) cannot confine the jet material as it moves further from the core. The measured collimation profile corresponds to a slowly decreasing density, and more steeply decreasing pressure gradient in the external medium. Since the closest jet width measurement is only at 1200 gravitational radii from the core (here the jet width is 750 gravitational radii), it cannot confirm the wide jet base measured by Giovannini et al. (2018) at 350 gravitational radii. Based on this result, we arrive at the same conclusion as Giovannini et al. (2018), that the jet is either launched from the accretion disk, or it is ergosphere-launched, but undergoes a quick lateral expansion below 1000 gravitational radii.

The distribution coefficients of radium in Olkiluoto potassium rich biotite were obtained by batch sorption experiments carried out as a function of the concentration of radium and barium. The batch sorption experiments were carried out with four different Olkiluoto associated reference groundwater types: fresh mildly reducing granitic reference groundwater ALLMR (or modified Allard granitic water), glacial anoxic meltwater OLGA, carbonate containing reducing brackish reference groundwater OLBA, and saline reducing reference groundwater OLSR. The main focus of the experiments was to evaluate the effect of the water salinity on the sorption of radium on biotite. The results were compared with sorption results obtained in previous studies done on radium and radium’s physicochemical analogue barium. According to the sorption results, the distribution coefficients of radium on biotite were largest in lower salinity waters. As the barium concentrations of the sorption solutions were increased, the distribution coefficients of radium generally stayed level until they decreased noticeably in the higher studied Ba concentrations (10E-3 and 10E-4 mol/l). This suggests that radium is a poor competitor in the ion exchange adsorption interactions on the surface of biotite, when other cations are present in the solution. As a unique case amongst the more predictable reference groundwaters, the brackish OLBA behaved differently. Despite the increasing salinity of the sorption solutions, the apparent sorption of radium increased steadily throughout the barium isotherm. It was concluded that the high concentration of sulphate in the OLBA reference groundwater caused the occurrence of coprecipitation of radium with the added barium and sulphate as (Ba,Ra)SO4.

Radium (Ra) is a naturally occurring radioactive metal, which is formed by the decay of uranium-238 and thorium-232 in the environment. In nature, radium occurs at trace levels in virtually all water, soil, rock and plants. 226Ra-, 228Ra, 224Ra, and 223Ra-isotopes are the most common isotopes of radium, and all isotopes are radioactive. The aim of the work was to study the behavior of radium in nature. In general, radium isotopes with variable activity concentrations in water and solid samples such as soil, and sediment can be measured with alpha- or gamma spectrometry or liquid scintillation counting (LSC). In this work, the measurements were done using gamma spectrometry with a Ge-detector, which is a semiconductor detector made of germanium. In addition, a very low level liquid scintillation spectrometer (Quantulus 1220) was also used. The determination of the PSA value (Pulse Shape Analysis) was successful and was determined experimentally with a Ra-226 standard sample. The activity of the Ra-226 standard sample obtained with Ge detectors was almost of the same order of magnitude as both theoretically and experimentally determined activities. The determined Ra-226 activities in water samples with gamma spectrometry were in good agreement with the activities obtained by LSC using α/β-discrimination

The Jokeri-Rail is a circular public transport line planned for the Helsinki area. According to the plan the route of this modern light rail goes between Tapiola-Leppävaara-Oulunkylä-Itäkeskus. The route is similar to the current Jokeri-bus line number 550 but the light rail would bring more capacity and reliability. The aim of this study was to determine the land use on the sphere of Jokeri's influence at the present moment and in the future when the rail line is operating. The main research questions are how the Jokeri-Rail would chance the land use in the area and which are the most important nodes and targets for development. One of the questions is will Jokeri-Rail have effect on the urban structure in the metropolitan area of Helsinki. The main data used for the study has been the SeutuCD'10, which is made by Helsinki Region Environmental Services Authority. From this geographical data population and employment levels, building stock as well as green area placement was studied. In addition to these spatial analyses discussions and expert interviews were also used. The literature review and a number of articles suggest that light rail transport systems have impact on both the structure and the economy of the city. On the impact area of the rail the value of the land will rise and the city structure will become denser. The geographical spatial analyses lead to a conclusion that the Jokeri-Rail will connect e.g. recreational areas with each other as well as residential areas to commercial areas. The interviews give more support for the conclusions found in the theory. Joker-Rail would make the urban structure denser and it would improve the public transport system by making it easier to perceive, as well as making it more reliable. The most important nodes and development areas along Joker-line would be Oulunkylä, Leppävaara, Huopalahti and Itäkeskus. The negative side effects of the light rail would be mainly affecting the residents who do not want the route on their back yard or the residents who's stop arrangements would be disadvantageous. Based on the interviews made for this study it can be stated that Jokeri-Rail has a broad support among experts. Because the impact of the Jokeri-Rail on the land use is significant, it would be important to strengthen the co-operation of different organizations so that the transport and urban land use planning would be done together. The implementation of Jokeri-Rail would support the urban structure and development of the metropolitan area. It would bring a new zone where the tramway would be competitive with a private car. The findings of this study support the Jokeri-Rail realization from planning to implementation as soon as possible.

Ilmakehätutkimuksessa ilmanpaineliitäntäinen lentoaikamassaspektrometri nitraattivaraimella (NO3-CI-APiToF) on osoittautunut hyväksi instrumentiksi ilmakehän hivenkaasujen mittauksessa. Alustavat kokeet ovat osoittaneet sen soveltuvan myös räjähdysaineiden mittaamiseen vastaavina hivenpitoisuuksina. Tämän työn tavoite on osoittaa menetelmän käyttökelpoisuus realistisissa olosuhteissa eri räjähdysaineille. Lisäksi vertailtiin kolmea erilaista varauslaitekonfiguraatiota: ilmakehätutkimuksessa käytettyä sekä kahta erilaista yksinkertaistettua mallia. Lähestymistapa oli käytännönläheinen: eri räjähdysaineille määritettiin havaintorajat taustallisessa ja aikarajoitetussa mittauksessa. Havaintorajalla tarkoitetaan pienintä todellista pitoisuutta, mikä voidaan erottaa 95% varmuudella taustamittauksesta yhdellä 12 sekunnin mittauksella. Tutkitut räjähdysaineet 1,3,5-trinitroperhydro-1,3,5-triatsiini (RDX), pentaerytritolitetranitraatti (PETN), trinitrotolueeni (TNT), triasetonitriperoksidi (TATP) ja heksametyleenitriperoksididiamiini (HMTD) ovat kaikki voimakkaita yksikomponenttiräjähdysaineita, jotka edustavat erilaisia kemiallisia rakennetyyppejä. Näytekaasu tuotettiin kiinteästä räjähdysainepinnasta olettamalla kaasun saavuttavan tasapainohöyrynpaineen generaattorin matkalla. Aineet applikoitiin liuoksina teräksisen (RDX, PETN, TNT) tai polyeteenisen (TATP, HMTD) tukilangan päälle. Osa näytteistä ostettiin (PETN, TNT) ja osa syntetisoitiin (RDX, TATP, HMTD). Havaintorajat aineille olivat: RDX 80 ppq, PETN 98 ppq, TNT 84 ppt ja TATP 1,5 ppm. HMTD ei muodostanut havaittavia nitraattiaddukteja. Eri varauslaitteilla ei ollut merkittäviä eroja. Koska havaintorajan määritelmässä on jo otettu huomioon mittauksen satunnaisluonne, näille arvoille ei enää määritetty virherajoja. Tällainen virheraja olisi ns. ‘virheen virhe’. Kaikki räjähdysaineet HMTD:tä lukuun ottamatta pystyttiin havaitsemaan murto-osassa niiden normaalista höyrynpaineesta huoneenlämmössä.

Räjähdysaineiden laittoman käytön ja kuljetuksen vuoksi tarvitaan herkkiä, kestäviä ja nopeita kenttämittausmenetelmiä. Kenttäolosuhteet asettavat laitteille ja menetelmille aivan erityiset vaatimukset. Kannettavien laitteiden täytyy olla kevyitä ja niiden täytyy mahdollistaa mittausten tekeminen suoraan ilmakehässä, ilman suljettuja näyteastioita. Ilmakehässä esiintyy suurina pitoisuuksina happea, vetyä, typpeä ja hiiltä, jotka häiritsevät helposti näiden alkuaineiden määritystä räjähdysaineista. Useimmilla räjähdysaineilla on myös erittäin alhainen höyrynpaine, minkä vuoksi vaaditaan menetelmiä, joilla näyte voidaan analysoida suoraan kohteesta tai erilaisten materiaalien läpi. Koska usein räjähdysaine halutaan myös tunnistaa ilman, että itse näytteeseen tai sen ympäristöön kosketaan, tarvitaan yhä herkempiä kaukomittausmenetelmiä, joita voidaan käyttää jopa satojen metrien etäisyydeltä itse näytteestä. Spektroskopisilla menetelmillä selvitetään räjähdysaineiden sähkömagneettisen säteilyn aiheuttamaa absorptiota, sirontaa ja/tai heijastusta. Säteilyn eri aallonpituudet vaikuttavat eri tavoin aineen kanssa. Pro gradu-tutkielman kirjallisessa osassa keskitytään niihin spektroskopisiin tekniikoihin, joita käytetään räjähdysaineiden kvalitatiivisissa ja kvantitatiivisissa määrityksissä kenttäolosuhteissa. Spektroskopisista pinta-analyyttisistä tekniikoista käytetään yleisesti infrapuna-, Raman- sekä laser-indusoitua plasmaspektroskopiaa. Kätkettyjen räjähdysaineiden tutkinnassa sovelletaan yleisesti kuvantamistekniikoita, joissa säteilylähteinä käytetään mm. röntgensäteilyä sekä mikro- ja terahertsiaaltoja. Kaasufaasissa olevien räjähdysaineiden tutkinnassa sovelletaan mm. fotoakustista- ja ontelovaimenemisspektroskopiaa sekä optisia kaukokartoitusmittalaitteita. Räjähdysaineita voidaan myös määrittää niiden ytimien kvadrupolienergiatasoerojen perusteella. Tähän tarkoitukseen käytetään mm. ydinkvadrupoliresonanssispektroskopiaa. Pro gradu-tutkielman kokeellinen osio tehtiin Keskusrikospoliisin rikosteknisessä laboratoriossa. Projekti koostui kahdesta toisistaan riippumattomasta osasta: palojätepussien diffuusiomittauksista sekä kiinteäfaasimikrouutto- kuitujen soveltuvuudesta palojätenäytteiden jäämäanalyysiin. Diffuusiomittauksissa tutkittiin palojätenäytteiden keräykseen käytettävien palojätepussien läpi tapahtuvan diffuusion vaikutusta näytteiden kontaminaatioon ja diffuusiossa tapahtuvia säilytyksen ja varastoinnin aikana tapahtuvia muutoksia. Diffuusioon vaikuttavista tekijöistä selvitettiin päällekkäisten palojätepussien määrän, pussien säilytysajan, näytteen koostumuksen ja konsentraation vaikutusta yhdisteiden siirtymiseen palojätepussien läpi. Kiinteäfaasimikrouuttokuitujen soveltuvuusmittauksissa tutkittiin kolmen eri kuitumateriaalin soveltuvuutta diesel- ja moottoribensiinipolttonesteen sekä alkoholi-ketoniseoksen jäämäanalyysissa. Kuiduille optimoitiin parhaat lämmitys- ja adsorptioajat, joiden perusteella valittiin analyysiin soveltuvin kuitumateriaali. Kiinteäfaasimikrouutto-menetelmän tehokkuutta palavien nesteiden jäämäanalyysissa verrattiin perinteisesti käytettävään kaasuneulamenetelmään.

The Peräpohja Belt comprises Palaeoproterozoic supracrustal rocks deposited on the faulted and subsided Archean Pudasjärvi Complex. The Peräpohja Belt was folded and sheared during the following basin inversion. The stratigraphy of the belt is relatively well known but, despite the potential for mineral deposits, the area is still missing a thorough analysis of the geological structures. This work aims at providing a systematic analysis of the deformation style, structural evolution and strain partitioning of the Peräpohja Belt. The results can be further used in wider-scale interpretations on crustal evolution and in refining the prospectivity models of the Peräpohja Belt. During the field mapping of this work, some 500 outcrops were examined and over 1000 individual geological structure orientations were measured. The most critical parts of a database consisting of earlier observations were verified during the mapping, and several geological maps, geophysical raster data (magnetic, electromagnetic and Bouguer anomalies), digital elevation model and a few diamond drill core logs were also used in the work. Based on available data, structural form-line maps and cross-sections were made in GIS and 3D software and further used in belt-scale structural interpretations and structural analysis. In addition to new structural interpretations, major revisions to stratigraphical units and their inter-correlations were made especially on the northern side of the Belt. The complex fold-and-thrust patterns of the Peräpohja Belt were formed during a single prolonged tectonic event. Instead of highly varying belt-scale stress orientations, the complex structure mostly results from localized stress fields caused by block structures of the Archean basement. A large E-W- or NE-SW-trending fault zone cuts the belt in half, with southern side expressing structures mainly controlled by thin-skinned deformation, whereas the northern side is dominated by thick-skinned features originating deep in the basement. The earliest thin-skinned structures already formed during the beginning of the compressional deformation, but the thick-skinned structures were clearly mostly activated during later stages.

Sanakirjat ovat rakenteisia tekstejä. Sana-artikkeleissa on nähtävissä selvästi erotettavissa olevia rakenneosia. Painetun sanakirjan muuntaminen rakenteiseen muotoon ei kuitenkaan ole aivan suoraviivaista. Tässä tutkielmassa kerrotaan sanakirjan rakennekuvauksen määrittelyn ja painetun sanakirjan rakenteistuksen ongelmista. Esimerkkinä käytetään Kotimaisten kielten tutkimuskeskuksessa (Kotus) kirjoitettavan Suomen murteiden sanakirjan (SMS) rakenteistusprojektia ja sen yhteydessä määriteltyä rakennekuvausta. SMS:n rakennekuvausta verrataan kielitieteellisten aineistojen koodaamisessa yleisesti käytetyn Text Encoding Initiative -suosituksen sekä uuden ISO 1951:2007 -sanakirjastandardin määrittelemiin rakennekuvauksiin. Muuntamista testataan käytännössä kirjoittamalla XSL-muunnosskripti, joka muuntaa SMS:n aineiston ISOstandardimuotoon. Muunnosprosessin voi todeta olleen hyödyllinen, koska sen aikana paljastui ongelmia sekä SMS:n rakennekuvauksessa että itse standardin määrittelyssä. Tulosten avulla SMS:n koodausta voidaan kehittää edelleen. Lopuksi tarkastellaan standardien käytöstä yleisesti saatavia hyötyjä ja mahdollisuuksia soveltaa niitä Kotuksen sanakirjatyöhön.

With the rapid development of information technology, the network is playing a more and more important role in our life and penetrate to every corner of our life, such as responsible for computing and transacting in business industries, and make great contribution for social communication. However, at the same time, more and more network attacks appears and seriously endanger the security of network. Including the threads for wired network and wireless network. In this thesis, we rst talk about network security, including wired network security and wireless security, we discuss the current threads and attacks we face for the wired network and wireless network, then we introduced the current solution for these threads and attacks.At last,we demonstrate the whole process of session cookie hijacking by manually perform it.We proposed our solution which called random cookie protocol, and we did experiments to compare the performance with HTTP.