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This article introduces supervised machine learning to the study of German strategic culture, analyzing both how German strategic culture has changed and the impact of strategic culture on Germany'...

This article contributes to theoretical integration in foreign policy analysis, by integrating two explanatory concepts that have mainly been used separately, namely the strategic culture of elites and the operational code of individual decision-makers. The explanatory power of using both concepts is illustrated in a case study of Australian foreign policy regarding the multinational coalition against the Islamic State of Iraq and Syria. The main argument is that strategic culture can provide a reasonable explanation for Australia's overall military engagement in the coalition. However, to explain Australia's approach to the coalition, strategic culture must be complemented with the operational code. The article suggests that the character of strategic culture can influence the opportunities for decision-makers to have an individual impact on foreign policy.

This article aims at clearing up a widespread misunderstanding in previous research that the classical strategic perspective, based on the writings of Carl von Clausewitz and his contemporary follo...

This thesis aims at using novel machine learning techniques to test the dynamics of the Universe via the cosmological redshift-distance test. Currently, one of the most outstanding questions in cosmology is the physical cause of the accelerating cosmic expansion observed with supernovae. Simultaneously, tensions in measurements of the Hubble expansion parameter $H_0$ are emerging. Measuring the Universe expansion with next generation galaxy imaging surveys, such as provided by the Vera Rubin Observatory, offers the opportunity to discover new physics governing the Universe dynamics. In this thesis, with the long-term goal to unravel these peculiarities, we create a deep generative model in the form of a convolutional variational auto-encoder (VAE), trained with a "Variational Mixture of Posteriors" prior (VampPrior) and high-resolution galaxy images from the simulation project \texttt{TNG-50}. Our model is able to learn a prior on the visual features of galaxies and can generate synthetic galaxy images which preserve the coarse features (shape, size, inclination, and surface brightness profile), but not finer morphological features, such as spiral arms. The generative model for galaxy images is applicable to uses outside the scope of this thesis and is thus a contribution in itself. We next implement a cosmological pinhole camera model, taking angular diameter changes with redshift into account, to forward simulate the actual observation on a telescope detector. Building upon the hypothesis that certain features of galaxies should be of proper physical sizes, we use probabilistic triangulation to find the comoving distance $r(z,\Omega)$ to these in a flat ($K=0$) Universe. Using a sample of high-resolution galaxy images from redshifts $z\in[0.05,0.5]$ from \texttt{TNG-50}, we demonstrate that the implemented Bayesian inference approach successfully estimates $r(z)$ within $1\sigma$-error ($\Delta r_{\text{est}} = 140$ $(580)$ Mpc for $z=0.05$ $(0.5)$). Including the surface brightness attenuation and utilizing the avalanche of upcoming galaxy images could significantly lower the uncertainties. This thesis thus shows a promising path forward utilizing novel machine learning techniques and massive next-generation imaging data to improve and generalize the traditional cosmological angular-diameter test, which in turn has the potential to increase our understanding of the Universe. Denna avhandling syftar till att använda nya maskininlärningstekniker för att testa universums dynamik via det kosmologiska rödförskjutningsavståndstestet. För närvarande är en av de mest framstående frågorna inom kosmologi den fysiska orsaken till den accelererande kosmiska expansionen som observerats med supernovor. Samtidigt uppstår spänningar i mätningar av Hubble-expansionsparametern $H_0$. Att mäta universums expansion med nästa generations galaxundersökningar, såsom de som ska genomföras av Vera Rubin Observatory, ger möjlighet att upptäcka ny fysik som styr universums dynamik. I den andan skapar vi i den här avhandlingen en djup generativ modell i form av en "convolutional variational auto-encoder" (VAE), tränad med en "Variational Mixture of Posteriors" prior (VampPrior) och högupplösta galaxbilder från simuleringsprojektet \texttt{TNG-50}. Vår modell kan lära sig en "prior" om galaxernas visuella egenskaper och kan generera syntetiska galaxbilder som bevarar de grova dragen (form, storlek, lutning och ytans ljusprofil), men inte finare morfologiska egenskaper, såsom spiralarmar. Den generativa modellen för galaxbilder är tillämplig på användningar som inte omfattas av denna avhandling och är därmed ett bidrag i sig. Därefter implementerar vi en kosmologisk hålkameramodell, med vilken hänsyn till förändringar i vinkelstorleken med rödförskjutning tas, för att framåt-simulera den faktiska observationen på en teleskopdetektor. Med utgångspunkt från hypotesen att galaxer i grunden borde ha gemensamma egenskaper med liknande fysiska storlekar, använder vi probabilistisk triangulering för att hitta avståndet (s.k. "comoving distance") $ r (z, \Omega) $ till dessa i ett platt ($ K = 0 $) universum. Med hjälp av ett urval av högupplösta galaxbilder från rödförskjutningar $ z \in [0.05,0.5] $ från \texttt {TNG-50} visar vi att den implementerade "Bayesian inference"-metoden framgångsrikt uppskattar $ r (z) $ inom $ 1 \sigma $ felmarginaler ($ \Delta r _ {\text{est}} = 140 $ $ (580) $ Mpc för $ z = 0,05 $ $ (0,5) $). Att inkludera dämpning i ytljusstyrka med rödförskjutning och att använda den massiva mängd av kommande galaxbilder skulle kunna minska den erhållna osäkerheten betydligt. Denna avhandling visar således en lovande väg framåt med nya maskininlärningstekniker och kommande enorma mängder av galaxbilder för att förbättra och generalisera det traditionella kosmologiska vinkeldiametertestet, vilket i sin tur har potentialen att öka vår förståelse om universum.

Ensuring safety through set invariance has proven a useful method in a variety of applications in robotics and control. However, finding analytical expressions for maximal invariant sets, so as to maximize the operational freedom of the system without compromising safety, is notoriously difficult for high-dimensional systems with input constraints. Here we present a generic method for characterizing invariant sets of nth-order integrator systems, based on analyzing roots of univariate polynomials. Additionally, we obtain analytical expressions for the orders n ≤ 4. Using differential flatness we subsequently leverage the results for the n = 4 case to the problem of obstacle avoidance for quadrotor UAVs. The resulting controller has a light computational footprint that showcases the power of finding analytical expressions for control-invariant sets.

Studies on aquatic biodiversity in different waterbody types have attracted significant attention worldwide to achieve the goal of freshwater conservation. Different freshwater habitats can help maintain regional biodiversity by directly supporting aquatic plants and forming networks to promote aquatic dispersal across regions. However, few studies have conducted large-scale comparisons of macrophyte diversity among different waterbody types in China due to a lack of a national macrophyte dataset. Here, we compared species richness, species composition, beta diversity, and its components among ponds, ditches, disturbed ponds, lakes, rivers, and reservoirs in southern China. We found that macrophyte species composition overlapped in the different waterbody types, indicating similar regional species pools. Species composition was best explained by temperature, elevation, and flow velocity. For species richness, ponds supported the highest number of species, followed by lakes, ditches, rivers, and reservoirs, with disturbed ponds showing the lowest diversity. For beta diversity, the relatively low turnover and high nestedness in the lakes indicated high dispersal of macrophyte species throughout these water bodies or suggested that human disturbance in lakes may lead to a more uniform chemical environment and thus regional macrophyte community. This study emphasized the importance of maintaining the diversity of different waterbody types in the landscape and determining the most threatened freshwater habitats. Moreover, small water bodies (e.g., ponds) contribute more to the regional macrophyte species pool than permanent water bodies (e.g., lakes) due to their relatively high biodiversity value. Their stable hydrological environment may help maintain rare and uncommon species that do not appear in other waterbody types.

This article contributes to an explanation of why Poland, after a period of almost two years’ hesitation, decided to dispatch military forces to the United States-led coalition against the Islamic ...

The damming of rivers results in hydrological modifications that not only affect the aquatic ecosystem but also adjoining terrestrial systems. Thirteen dams commissioned along the Wujiang River hav...

This article integrates literature on strategic culture with literature on the domestic politics of foreign policy, illustrating how the interaction of culture and domestic political calculation ca ...

This article investigates how strategic culture influenced the decision-making of Australia and Poland regarding the global coalition against the Islamic State. In the coalition, Australia has followed its tradition of active participation in United States-led operations, while Poland has embarked on a more cautious line, thereby breaking with its previous policy of active participation. The article examines how Australian and Polish responses to the coalition were shaped by five cultural elements: dominant threat perception, core task of the armed forces, strategic partners, experiences of participating in coalitions of the willing, and approach to the international legality of expeditionary operations. It finds that Australia and Poland differed on all five elements but that the major differences are found in dominant threat perception and core task of the armed forces.

Den senaste teknologiska utvecklingen har gjort det möjligt att miniatyrisera optiska komponenter ner på ett fotoniskt integrerat kretskort. Sammankopplingen mellan olika komponenter möjliggörs av vågledare, i vilka informationsbäraren, en enskild foton, propagerar. En förutsättning för fungerande fotoniska chip är effektiv koppling av icke-klassiskt ljus in i kretsen. I detta arbete har denna kopplingseffektivitet från en fotonkälla, approximerad som en dipol, in i en vågledare simuleringats. Ett vanligt förekommande material med högt brytningsindex, kiselnitrat Si3N4, har använts som bandvågledare, placerad på ett underlag av kiseloxid SiO2 och med luft runtomkring. För att lösa Maxwells ekvationer i vågledarstrukturen har finita differensmetoden i tidsdomän (FDTD) använts i mjukvara från Lumerical. Det visas att för ljusspektrat med våglängder från 750 till 800 nm och en vågledare med tvärsnitt 600x250 nm, propagerar de fundamentala transversella elektriska (TE) och transversella magnetiska (TM) moderna. Kopplingseffektiviteten visas nå värden på 7 % i varje rikting när dipolen placeras ovanpå vågledaren. Om dipolen däremot placeras framför vågledaren nås en kopplingseffektivitet på över 50 %. Vidare visas det att 2D-fotonkällor som ligger i vågledarens plan, approximerade av dipoler i vågledarens plan, ger bättre resutlat än motsvarande ur dipolens plan. Dessa resultat presenterar sålunda bevis för att det är möjligt att nå avsevärt större koppling av ljus från kvantprickar av 2D-material än vad som åstadkommits experimentellt. Recent technological advances have made it possible to miniaturize and integrate optical components in quantum circuits. The connection between different components is enabled by waveguides, which support the propagation of the information carrier, a single-photon. A prerequisite for functioning quantum photonic chips is the efficient coupling of non-classical light into the circuit. In this work, this coupling efficiency from an on-chip single-photon source, approximated by a dipole, into a waveguide has been simulated. The high refractive index material silicon nitride Si3N4 has been used as a strip waveguide, placed on top of a silicon oxide SiO2 wafer with surrounding air. To solve Maxwell’s equations in the structures, the finite difference time-domain (FDTD) method has been used through software by Lumerical. It is shown that for the light spectrum with wavelengths 750 to 800 nm a waveguide with cross section dimensions 600x250 nm supports the fundamental transversal electric (TE) and transversal magnetic (TM) modes. The coupling efficiency is shown to reach 7 % in each direction when the dipole is placed on top of the waveguide. Having the dipole on in front of the waveguide, however, results in over 50 % coupling in the forward direction. Additionally, it is shown that in-plane 2D-material single-photon emitters, approximated by in-plane dipoles, give better results than out-of-plane dipoles for most of the tested configurations. In conclusion, these results present evidence for a substantially higher coupling efficiency from 2D-material quantum dots than have been achieved in experiments.