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Työ käsittelee Finnish Jabal Haroun Project -tutkimusryhmän Etelä-Jordaniasta inventoimalla keräämää arkeologista aineistoa (vuosilta 1999-2005) tietutkimuksen kannalta. Työn tarkoituksena on selvittää, miksi tutkimusalueella, Aaronin vuoren ympäristössä, sijaitsee tien jäänteitä ja miten tie on maastossa muinoin kulkenut. Lisäksi työ analysoi tien varsilla havaittujen rakennusten jäännösten suhdetta tiehen ja pyrkii ajoittamaan tien käyttöajankohdan (ajankohdat). Työn alkuoletuksena on, että pääosa tienvarsirakennuksista on liitettävissä tiehen ja tien sijoittuminen tutkimusalueelle johtuu pitkälti lähistöllä sijaitsevan Petran noususta merkittäväksi, Nabatealaisten harjoittaman kaupan keskukseksi, Lähi-idässä ajanlaskun alkuun mennessä. Tien jäänteitä tarkastellaan maisema-arkeologisin perustein. Tämä tarkoittaa sitä, että analyysissä korostuvat sekä kulttuuriset että ympäristölliset vaikuttimet. Niiden välistä, aikaan sidottua, suhdetta arvioidaan menneen ihmistoiminnan selittämiseksi. Tutkimusmenetelmät ovat paikkatietojärjestelmien soveltaminen, kohdekohtainen arkeologisen aineiston ja sijainnin tutkiminen, vertailevan aineiston käyttö sekä kolmiulotteinen tarkastelu. Tie ajoitetaan tienvarsikohteiden keramiikkalöytöjen avulla sekä rakenneanalyysin perusteella. Tutkimus osoittaa tien syntyneen alueen sijainnin takia. Sijainti oli edullinen suhteessa luonnonvaroihin, asutuskeskuksiin ja luontaisiin kulkuväyliin. Tien rakentajat osasivat taidokkaasti hyödyntää alueen luonnonpiirteitä ja käyttivät erityisiä menetelmiä vaikeiden tieosuuksien turvaamiseksi luonnonvoimien tuhoilta. Suurin osa tienvarsirakenteista voidaan katsoa johtuvan suoraan tien olemassaolosta, pieni osa rakenteista palveli pääsääntöisesti muita maankäytön muotoja. Petran vaikutus tien olemassaoloon ja muotoon oli suuri, kaupungin kehitys ja kukoistus näkyvät tiehen liitettävässä arkeologisessa aineistossa. Tien aktiivinen käyttö näyttää jatkuneen myös Roomalaisaikaan ensimmäisille vuosisadoille jKr., jonka jälkeen se hitaasti hiipui.

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

Climate change is predicted to cause changes in vegetation productivity and biomass in northern areas. Understanding the factors affecting biomass helps us to estimate the future changes in plant communities and the amount of carbon stored in vegetation. In this thesis I examine the effects of soil properties (soil moisture, temperature, pH and calcium), geomorphological processes and topography on the small scale variation of aboveground vascular biomass. I also compare two biomass variables: the dry weight of a biomass sample and the vegetation volume. The data was collected during summer 2011 on the northern slopes of fell Saana, north western Finland. Modeling was done with generalized linear models (GLM) and also with generalized estimation equations (GEE) since they are able to take spatial autocorrelation into account. Variation partitioning was used to find out the single and combined effects of variable groups (soil, geomorphology and topography). The connections between the most common plant species and the biomass variables were also studied. Soil properties have a stronger impact on both biomass variables. Soil group alone explains 7 % of variation in the dry weight of biomass and 20 % of variation in vegetation volume. Geomorphology explains 4,7 % of variation in the biomass dry weight and 14,5 % in vegetation volume. Topography has the least effect on the biomass variables (2,2 % and 2,0 %). The combined effects of groups are also relatively strong, e.g. the combined effects of geomorphology and topography explain 9,7 % of variation in vegetation volume. Models with vegetation volume as a response variable were able to explain more of the variation (unexplained variation 48,7 %) than models of biomass dry weight (67,1 %). Also the relative importance of the variable groups differed for the two biomass variables, e.g. the soil group affected vegetation more than biomass dry weight. Both biomass variables correlated strongly with the two species with the largest coverage on the study site, crowberry (Empetrum nigrum ssp. hermaphroditum) and dwarf birch (Betula nana). The correlation of crowberry with vegetation volume was stronger than with biomass dry weight. Even though the models explain only about half of the variation, results suggest that soil properties and geomorphological processes have a clear impact on vegetation biomass. The impact of topography is strongly linked to other variable groups. A large amount of the unexplained variation and the importance of the combined effects of variable groups are due to the complexity of the factors controlling vegetation biomass. This makes it more complicated to predict the future changes of vegetation biomass. Changes will depend on how rising temperatures and increasing rainfall will affect not only soil properties and geomorphology but also all the factors that are behind the unexplained variation of biomass in the models.

Soil moisture plays a key role in ecosystems. Soil moisture varies spatially and temporally, and the variations are influenced by many different factors. On a large scale, climate has a large effect on soil moisture, but more locally, especially topography, soil and vegetation become important factors. In addition, mean soil moisture content affects whether soil moisture variations are greatest when soil is dry or moist. Climate change will significantly affect soil moisture around the world, and effects will also be visible in the boreal forest. Therefore, it is important to study soil moisture more comprehensively in boreal environment. The purpose of this thesis is to find out how soil moisture varies spatially and temporally, and how topography, soil and vegetation explain this variation in different parts of the boreal forest and in different environments. Study area covers eight areas of varying size (3,5–37 km2) in the boreal forest around Finland. Each study area has 44–96 study points from which soil moisture has been measured every 15 minutes during July 2020. Mean and standard deviation of soil moisture (response variables) of each research point were calculated from the measurements, of which the mean describes the spatial variation of soil moisture and the standard deviation the temporal variation. The response variables were explained by environmental variables. Variables explaining topography’s effect were altitude, SAGA wetness index (SWI), topographic position index (TPI) and radiation. Vegetation was explained by canopy cover and site fertility class, and soil was explained by soil class. The effect of environmental variables on spatial and temporal variations of soil moisture was analysed using a generalized additive model (GAM), which was fitted for each study area and for both response variables separately. Explanatory power of the models was examined with an adjusted R2 value using the bootstrap method. Relative importance of the individual environmental variables in the model was examined by randomizing the variables, and the direction of the effect of the environmental variables was examined using response curves. Soil moisture varied considerably spatially and temporally within the study areas and between the areas. Soil moisture was generally high in study areas with a lot of peatlands, and moisture varied most spatially usually in topographically heterogeneous areas. Often, the temporal variation of moisture was highest on dryer study areas and lowest on moister areas. Indeed, it was found that when the mean soil moisture was high, the standard deviation was often small and vice versa. Topographic factors influenced to the mean and standard deviation of soil moisture more in the northern than in the southern regions, while the role of canopy cover was emphasized in the southern regions when explaining the mean moisture. Soil influenced to the moisture more in the northern than in the southern areas. From all variables, SWI clearly explained the best both the mean and standard deviation of moisture. Canopy cover and radiation also explained well the mean moisture in a part of the study areas. In addition to SWI, the standard deviation of moisture was best explained by site fertility class and soil class. Altitude and TPI rarely explained the mean and standard deviation of moisture well. SWI often increased moisture and decreased moisture’s temporal variability in the study areas, but the directions of the effects of other environmental variables varied a lot between areas. This study shows that the large spatial and temporal variability of soil moisture in different environments of the boreal forest is dominated by different factors, and even the same environmental factors affect soil moisture in very different ways between areas. Research must be continued to get a better general picture of the factors affecting soil moisture variations in the boreal forest, and to be able to prepare better for the environmental changes caused by climate change.

Satellite positioning is vulnerable to interference due to the power of satellite signals. Satellite signals are exceptionally weak when they arrive to the Earth and therefore susceptible to radio frequency interference (RFI). This makes even low-power interference effective, possibly for radius of several kilometers. Global Navigation Satellite System (GNSS) services, such as positioning, navigation and timing services (PNT), are widely used among our society by civilians and authorities. Critical infrastructures, such as money transfer and electricity transmission networks, rely on accurate timing data provided by GNSS’s atomic clocks. These services are under a serious threat by RFI —intentionally created or not. In the areas that GNSS jamming signal can cover, the PNT services are most likely degraded or entirely unavailable. The easiest way to intentionally create RFI is to create jamming interference by broadcasting empty signal on satellite signal frequency with simple jamming radio devices aka jammers. Jammers disturb GNSS services by blocking entire positioning data or deteriorating positioning accuracy which leads to inaccurate location information. Jamming is an emerging global threat for GNSS services since jammers can be easily bought online, even though jamming is illegal in Europe and many other regions. Incentives for jamming differ by the user group of jamming equipment. Civilian jamming is mostly done with low-power jammers for protecting privacy by hiding location information and it is normally done without further knowledge about the effects for the surrounding environment. The more severe threat is done with high-power jamming equipment by professionals. This kind of interference has motives for either disturbance or denial of GNSS services or to defend against different location-based measures. Jamming and RFI are significant parts of electronic warfare. This study tested the usability of MATLAB’s RF Toolbox on simulating jamming signals horizontally in different topographies across Finland to demonstrate how spatially effective jamming actually is. Used jamming signals were simulated with four different powers on Galileo’s E1 and GPS’s L1 signal (1575.42 MHz) to exemplify the effects of different power interference. The simulations and inspection of signal propagation were done with MATLAB by visualizing the expected power of jamming signal and calculating propagation loss for receiver matrix above digital elevation model (DEM). The used method was not able to calculate propagation values for varying power and exact values for signal attenuation of jamming signal cannot be calculated with MATLAB. RFI is illegal in Finland, therefore field work is not possible for this kind of study. This study highlights the hindering or blocking effect of topography on jamming signal propagation alongside with the effectiveness of different jammer power levels. Signals obey signal propagation models, but topographic characteristics, such as hills, have an ability to hinder the propagation. The results emphasize the spatial effects of even low-power jammers that are used by civilians and accentuates the significance of topography to signal propagation. Effective jamming over different topographic characteristics can be conducted with even 500 mW jammer and increase of jammer power is able to cover extensive areas of irregular terrain. The most vulnerable areas to GNSS jamming are open, unbuilt areas. However, the impact of locally bounded urban jamming scenario is also severe to the population and infrastructures of the area.

Majorana quasiparticles are zero-energy modes theorised to exist at the boundaries of topological superconductors. Due to their topological protection and non-Abelian exchange statistics, Majorana quasiparticles have in recent years garnered much interest within the condensed matter community as a promising platform for fault tolerant quantum computing. To this end, theorists constantly attempt to come up with new experimentally feasible models that can host these quasiparticles. In this thesis, we investigate a recent proposal for realising an effective topological superconductor with Majorana quasiparticles, namely the helical Shiba chain. The system consists of a one-dimensional array of magnetic impurities deposited on a conventional superconductor, such that the overall magnetic texture is helical. A single impurity hosts a bound electron state with an energy within the superconducting gap. For many impurities, these so called Shiba states hybridise and form energy bands, that for a certain range of parameters support topological superconductivity and Majorana bound states at the ends of the chain. Prior to this work, the Shiba chain has only been studied in the deep-dilute limit where the energies of the individual Shiba states are assumed to be very close to the centre of the gap, and the magnetic impurities are placed sufficiently far away from each other as to keep the resulting bands deep within the gap. By re-expressing the problem in terms of a non-linear eigenvalue equation, we go beyond this limit and extend the study of the topological properties of the Shiba chain to a novel domain of experimental interest — a domain which has until now remained unexplored. We compare our results with previous work and observe an agreement between our more general theory and the deep-dilute limit in the expected parameter regime. However, qualitative differences emerge when the coherence length of the underlying superconductor becomes very large.

In this thesis, we examine a fairly novel area of physics that concerns topological materials, and in particular, topological superconductivity. A goal in the research of topological materials is realizing applications in quantum computing, which could be aided by the emergent quasiparticles that exhibit non-Abelian exchange statistics. These are called Majorana bound states, and they are elusive quasiparticles predicted to be found on the boundary of topological superconductors. We first study a one-dimensional chain of potential impurities placed on the surface of a two-dimensional $p$-wave superconductor. As is usually the case, such chains are composed of perfect lattice structures, which is very challenging to achieve in any laboratory setting. Nevertheless, they serve as a good example of systems where an analytical solution can be well established. We investigate the model without employing any deep-dilute approximation, which gives us an accurate description even far away from the gap center. This is done by formulating the problem as a non-linear eigenvalue equation, which complicates it significantly, but also extends the region of applicability of our theory. We use reciprocal space calculations of two topological invariants to obtain the topological phase diagram of the system. The model is shown to host topological quasiparticle excitations at the ends of the chain, with multiple distinct topological phases. The near-perfect localization of the excitations makes them good candidates for probing Majorana bound states in experimental setups. We then move on to study topological superconductivity in random lattices, as opposed to regular structures which assume arbitrary precision. We frame our work starting with the mathematics of random numbers. Our work is thus in stark contrast with previous studies on topological materials that start off with a perfect lattice structure, and investigate some degree of disorder as perturbations to the regular lattice case. Our work establishes a first-ever realistic candidate for realizing topological superconductivity in an amorphous material. This could enable a novel approach to creating topological materials, and drastically aid in the development of fault-tolerant quantum computing.

The topic of this work is Aristotle’s doctrine of the intellect (ὁ νοῦς) as the noetic faculty of the soul in the psychology of the De anima. The work is based on scholarly exegesis of Aristotle’s text and philosophical analysis of his arguments. This work also reviews some of the most prominent interpretations of the topic up to the present. While most research on the topic seems to have focused primarily on ontological issues, the aim of this work is to assess the question of what kind of an activity Aristotle ascribes to the intellect as a faculty of the soul. To this end, I separate between two forms of rationality in Aristotle’s psychology, noetic and discursive rationalities. Close reading of Aristotle’s considerations of rational capabilities in the De anima shows that he separates between these, and furthermore that the characteristic activity of the intellect (νοεῖν) is best understood in terms of the former. I also discuss the method of defining capacities in Aristotle’s faculty psychology and give reasons for thinking that the doctrine of the intellect stands for a higher, separate reality in Aristotle’s psychology and is not contained in the common account of the soul. In approaching the topic of the intellect, I discuss the way that Aristotle aims to overcome the shortcoming of Anaxagoras’ theory with his doctrine of the potential (δύναμις) intellect. The central account of the intellect’s noetic activity in the De anima is given in terms of receptivity (δεκτικός) and is borne out of an analogy with sense perception. The analogy implies an explanation of the intellect’s activity with the model of efficient cause. But Aristotle’s considerations of the nature of the intellect also show him detaching it from the faculty of sense due its difference in scope, discussed in terms of limitlessness or neutrality of the intellect. In this work I argue that the characterizations that Aristotle gives of the intellect’s characteristic activity prevents from reading it as thinking in the broad sense of the term. However, it is possible to take Aristotle’s focus to be with thinking in his account of the intellect. In this work my aim is to give reasons for why this reading is unsuccessful and to provide an alternative, which argues that the cognitive activity of the intellect in the De anima is rather best understood by associating it with theoretical knowledge. In my reading the activity of the intellect does not stand for ordinary thought but for the most successful form of rationality available to humans, which is a veridical and direct kind of cognition that is of starting points of explanatory sciences. The activity of the intellect is primarily for Aristotle reception of form (εἶδος), as is shown by his characterization ‘place of forms’. In conformity with the traditional reading of Alexander of Aphrodisias, the noetic faculty of the soul is in my reading never the actual locus of forms but only the dispositional capacify for participating in the life of active understanding.

Julkinen tila on kaupungissa keskeinen tekijä ja tori on julkisista tiloista leimallisin. Historiallisesti torien merkitys kaupungissa on suuri ja vaihdellut historian aikana. Tori on mielenkiintoinen keskus kaupungissa: dynaaminen ja eläväinen torikaupan aikoina, hiljainen ja autio niiden ulkopuolella. Julkisten tilojen monipuolistuminen on asettanut torit asemaan, jossa ne eivät enää ole ensisijainen kokoontumispaikka. Tori elää kaupungin mukana ja saa kehityksen tuloksena uusia funktioita. Tutkimus selvittää näitä käyttötarkoitusten muutoksia käyttäen tapausesimerkkinä Porvoon toria 1832–2021. Tutkimus on saanut alkunsa Porvoon kaupungin keskustakehittämishankkeesta, johon liittyen tutkimuksen tekijä laati toriympäristön historiaselvityksen vuonna 2020. Tutkimuksen metodina on temaattinen tarkastelu, joka torin historiallisia vaiheita vertaamalla ja yhteiskunnalliseen kontekstiin asettamalla vastaa kysymykseen, kuinka torin muuttuvat funktiot ovat vaikuttaneet sen rooliin kaupungissa. Lähdeaineisto koostuu arkistolähteistä, valokuvista, sanomalehtijulkaisuista täydennettynä toriyrittäjien haastatteluilla. Kirjallisuus hyödyntää erityisesti julkisen tilan piirteitä sekä Porvoon historiaa selvittäneitä teoksia. Tutkimuksen teoreettinen viitekehys soveltaa Lefebvren tilan tuotannon teoriaa korostamalla ihmisen oikeutta kaupunkiin ja toria kaupunkilaisten arjen tilana. Teoria tarjoaa perustan kaupunkisuunnittelun historiassa tehtyjen arvovalintojen tutkimiseen. Tutkimus teoretisoi myös tilaa suhteellisena käsitteenä ja tarkastelee paikan merkitystä kaupungissa siihen liitettyjen mielikuvien avulla. Tutkimus jakaa torin neljään toiminnalliseen funktioon, jotka ovat tulleet torille eri aikoina, mutta ovat kaikki läsnä nykyisin. Ensimmäinen funktio, torikauppa, on pitkään hiipuneenakin yhä elävä torin käyttötarkoitus. Toinen funktio on torin symbolisesti merkittävä edustusrooli. Se näkyy paitsi torin varrelle sijoittuneissa instituutioissa myös torin ajoittain korostuvassa roolissa kansalaisaktivismin näyttämönä. Kolmas funktio on kaupungin keskeisenä liikennealueena toimiminen. Keskeinen sijainti on tuonut torille linja-auto- ja taksiasemat, jotka ovat merkittävästi muokanneet torikuvaa 1930-luvulta tähän päivään. Neljäs funktio on tapahtumapaikka, joka liittyy kaupunkikeskustojen kehittämisen trendiin. Tori tarjoaa puitteet niin perinteisten kuin uusien kaupunkitapahtumien paikkana. Lisäksi tutkimus vertaa Porvoon toria kolmeen muuhun suomalaiskaupungin samanikäiseen toriin ja niiden historiaan. Torien taustojen analysointi selvittää, miksi ne ovat kehittyneet eri tavoin ja asettaa Porvoon torin historian laajempaan yhteiskunnalliseen kontekstiin.

Syksyllä 2007 sekä 2008 tapahtuneet kouluampumiset järkyttivät maatamme suuresti. Näissä iskuissa kuoli yhteensä 20 ihmistä ja haavoittui useita. Näiden tekojen jälkipuinnissa sekä oikeuskäsittelyssä viimeistään yleiseen tietoon tuli, että Suomessa törkeänkään henkirikoksen tai törkeän ryöstön valmistelu ei ole ollut rangaistavaa. Oikeuskäsittelyn aikana ilmi tuli, että kyseinen epäkohta oli myös ulkomaalaisten rikollisliigojen tiedossa, sillä Liedon iskua seuranneessa oikeuskäsittelyssä he vetosivat nimenomaisesti tähän, että rikoksen valmistelu ei ole Suomessa rangaistavaa, toisin kuin esimerkiksi Ruotsissa ja useissa muissa maissa. Tämän jälkeen myös Suomessa alettiin valmistella kyseisten valmistelutekojen kriminalisoimista. Valmistelukriminalisointeihin voi katsoa liittyvän myös ongelmia. Rangaistusvastuuta ei saa ulottaa liian olemattomiin valmistelutekoihin, ettei ketään rangaista pahoista aikeista. Rikosoikeudessa lähtökohtaisesti on suhtauduttu torjuvasti valmistelukriminalisointeihin. Jos rikosta miettii aikajanan kautta, yleisesti voidaan ajatella, että idea kypsyy tekijän pään sisällä, josta edetään yrityksen kautta täytettyyn tekoon Tässä tutkielmassa on tarkoituksena selvittää, mitenkä uudehkoa lakia on oikeuskäytännössä tulkittu. Millaisista valmisteluteoista on annettu langettava tuomio ja milloin taas tuomitsemisen edellytykset eivät ole täyttyneet. Lisäksi tutkielmassa pyritään määrittämään millaista tuomitsemiskynnystä yleisesti voidaan pitää hyväksyttävänä kyseisessä rikoslajissa, ja mietitään mitenkä kriminalisointi vastaa sille asetettuja tavoitteita.