No description available.

Mobile agent technology presents an attractive alternative to the client-server paradigm for several network and real-time applications. However, for most applications, the lack of a viable agent security model has limited the adoption of the agent paradigm. This thesis presents a security model for mobile agents based on a security infrastructure for Computational Grids, and specifically, on X.509 Proxy Certificates. Proxy Certificates serve as credentials for Grid applications, and their primary purpose is temporary delegation of authority. Exploiting the similarity between Grid applications and mobile agent applications, this thesis motivates the use of Proxy Certificates as credentials for mobile agents. A new extension for Proxy Certificates is proposed in order to make them suited to mobile agent applications, and mechanisms are presented for agent-to-host authentication, restriction of agent privileges, and secure delegation of authority during spawning of new agents. Finally, the implementation of the proposed security mechanisms as modules within a multi-lingual and modular agent infrastructure, the Distributed Agent Delivery System, is discussed.

1 Abstract Extraordinary Renditions and Human Rights Ing. Petr Švepeš The topic of this thesis is Extraordinary Rendition as the phenomenon of contemporary counter- terrorism strategies and its critical reflection in light of International Human Rights Law. Extraordinary Rendition represents a controversial method of obtaining intelligence information about terrorist activities carried out worldwide by the CIA. This method is based on the identification of terrorist suspects who might know valuable intelligence, followed by their tracing and subsequent kidnapping with direct assistance or connivance of the state in whose territory that person is located. Kidnapped persons are secretly transported by private jets via the "global spider's web" to a selected country which practices advanced interrogation techniques using various methods of torture. In this country the persons are incommunicado imprisoned and interrogated by local authorities. Extracted intelligence information is then passed on to the CIA and the suspects in this country are either criminally charged and indicted, further imprisoned without formal charges or simply "disappear." The main objective of this thesis is to present a detailed human rights analysis of Extraordinary Rendition and to identify potential violations of binding norms of...

Studies in paleoclimate are important because they give us knowledge about how the climate system works and puts the current climate change in necessary perspective. By studying (pre)historic periods we increase our knowledge not just about these periods, but also about the processes that are important for climatic variations and changes. This thesis deals mainly with the interaction between climate and vegetation. Vegetation changes can affect climate in many different ways. These effects can be divided into two main categories: biogeochemical and biogeophysical processes. This thesis studies the biogeophysical effects of vegetation changes on climate in climate models. Climate models are a necessary tool for investigating how climate responds to changes in the climate system, as well as for making predictions of future climate. The biogeophysical processes are strongly related to characteristics of the land surface. Vegetation changes alter the land surface’s albedo (ability to reflect incoming solar radiation), roughness and evapotranspiration (the sum of evaporation and tran-spiration), which in turn affects the energy fluxes between the land surface and the atmosphere and thereby the climate. It is not, however, evident in what way; denser vegetation (e.g. forest instead of grassland) gives decreased albedo, which results in higher temperature, but also increased evapotranspiration, which contrastingly results in lower temperature. Vegetation changes are in this thesis studied in four different (pre)historic periods: two very cold periods with no human influence (c. 44,000 and 21,000 years ago), one warm period with minor human influence (c. 6,000 years ago) and a cold period with substantial human influence (c. 200 years ago). In addition to that the present climate is studied. The combination of these periods gives an estimate of the effect of both natural and anthropogenic vegetation on climate in different climatic contexts. The results show that vegetation changes can change temperature with 1–3 °C depending on season and region. The response is not the same everywhere, but depends on local properties of the land surface. During the winter half of the year, the albedo effect is usually most important as the difference in albedo between forest and open land is very large. During the summer half of the year the evapotranspiration effect is usually most important as differences in albedo between different vegetation types are smaller. A prerequisite for differences in evapotranspiration is that there is sufficient amount of water available. In dry regions, evapotranspiration does not change much with changes in vegetation, which means that the albedo effect will dominate also in summer. The conclusion of these studies is that vegetation changes can have a considerable effect on climate, comparable to the effect of increasing amounts of greenhouse gases in scenarios of future climate. Thus, it is important to have an appropriate description of the vegetation in studies of past, present and future climate. This means that vegetation has the potential to work as a feedback mechanism to natural climatic variations, but also that man can alter climate by altering the vegetation. It also means that mankind may have influenced climate before we started to use fossil fuel. Consequently, vegetation changes can be used as a means to mitigate climate change locally. / Studiet av paleoklimat är viktigt för att det ger kunskap om hur klimatsystemet fungerar samt för att det sätter nuvarande klimatförändring i ett nödvändigt perspektiv. Genom att studera (för)historiska perioder ökar vi vår kunskap om dessa perioder, men också om vilka processer som har betydelse för klimatets variationer. Denna avhandling behandlar framförallt interaktionen mellan klimat och växtlighet. Förändringar i växtligheten kan påverka klimatet på flera olika sätt. Dessa kan delas in i två huvudgrupper: biogeokemiska och biogeofysikaliska processer. Denna avhandling studerar de biogeofysikaliska effekterna på klimatet i klimatmodeller. Klimatmodeller är ett nödvändigt verktyg för att studera hur klimatet svarar på förändringar i klimatsystemet, samt för att göra förutsägelser om framtidens klimat. De biogeofysikaliska processerna är förknippade med markytans egenskaper. Förändrad växtlighet förändrar markytans albedo (förmågan att reflektera inkommande soltrålning), skrovlighet och förmågan att transportera vatten från marken till atmosfären genom evapotranspiration (summan av avdunstning och transpiration), vilket i sin tur påverkar energiflödena mellan markytan och atmosfären. Dessa förändringar påverkar sedermera klimatet. Det är emellertid inte självklart på vilket sätt; tätare växtlighet (t.ex. skog i stället för äng) ger minskat albedo vilket ger högre temperatur, men också ökad evapotranspiration vilket däremot ger lägre temperatur. Växtlighetsförändringars påverkan på klimatet studeras i denna avhandling i fyra olika (för)historiska perioder: två väldigt kalla perioder utan mänsklig påverkan (ca 44 000 och 21 000 år sedan), en varm period med liten mänsklig påverkan (ca 6 000 år sedan) och en kall period med avsevärd mänsklig påverkan (ca 200 år sedan). I tillägg till det studeras också dagens klimat. Resultaten visar att förändringar i växtlighet lokalt kan ha en signifikant effekt på klimatet. Kombinationen av dessa perioder ger en uppskattning av effekten av både naturlig och antropogen växtlighet i olika klimatsammanhang. Förändrad växtlighet kan ändra temperaturen med 1-3 °C beroende på årstid och område. Responsen är inte densamma överallt utan beror på lokala egenskaper hos markytan. Under vinterhalvåret är oftast albedoeffekten viktigast eftersom skillnaden i albedo mellan skog och öppet landskap då är mycket stor. Under sommarhalvåret är evapotranspirationen oftast viktigast eftersom skillnaden i albedo mellan olika växtlighetstyper då oftast är små. En förutsättning för det är att det finns tillräckligt med vatten tillgängligt för evapotranspiration. I torra områden förändras evapotranspirationen inte särskilt mycket när växtligheten förändras, vilket gör att albedoeffekten dominerar även på sommaren.  Slutsatsen av dessa studier blir att förändrad växtlighet kan ha en betydande effekt på klimatet, jämförbar med den effekt som ökade halter av växthusgaser har i scenarier för framtida klimat. Alltså är det viktigt att ha en korrekt beskrivning av växtligheten i studier av (för)historiskt, nutida och framtida klimat. Det betyder att växtligheten har potentialen att fungera som en återkopplingsmekanism till naturliga klimatvariationer, men också att människan kan påverka klimatet genom att förändra växtligheten. Det betyder också att mänskligheten kan ha påverkat klimatet innan vi började använda fossilt bränsle. Följaktligen kan växtlighetsförändringar användas som ett sätt att lokalt begränsa klimatförändringar. / <p>At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 4: Manuscript.</p>

This Bachelor’s thesis explores the relationship between borders, boundaries and migration, and their effect on identity making from a diasporic perspective. The study focuses on notions of national, regional, cultural, tribal and ethnic identity, and set in relation to the influence borders and boundarieshave on these processes. It investigates this topical realm within the specific conditions of the Angolan-Namibian border, following the developments from the era of colonization, independence struggle and decolonization and the transformation of Angola and Namibia into self-asserting and sovereign states, in which it focuses on the identity making of the Angolan diaspora residing in the border town of Rundu, northern Namibia. In doing so, it sets out to investigate the connection between macro variables and processes such as colonialism, the Cold War in Africa, and independence movements, to micro processes focusing on the living conditions and experiences of border residents. The study aims at a holistic approach drawing from theoretical developments within border and boundary studies stemming from disciplines such as political geography and anthropology, along with migration studies and social psychology. The results suggest that differing dominant conditions of the Angolan and Namibian states in terms of historical and political development, living conditions and the manifestation of the border and political assertion of the nation-states, has indeed helped to inform and construct different social categories and identities. In terms of the Angolan diaspora, the results indicate that migrants acquiring Namibian citizenships and thereby rights, did redefine their national identity to a greater extent than those denied documentation as their agency has become curtailed, leaving this group in an identity-limbo. The main contribution of this study is an investigation of what the border-migration-identity nexus means in terms of the Angolan diaspora and the Kavango region.

Doctor of Philosophy / Department of Computing Science / David Gustafson / The web is no longer composed of static resources. Technology and demand have driven the web towards a complex, dynamic model that tailors content toward specific client fingerprints. Servers now commonly modify responses based on the browser, operating system, or location of the connecting client. While this information may be used for legitimate purposes, malicious adversaries can also use this information to deliver misinformation or tailored exploits. Currently, there are no tools that allow a user to detect when a response contains tailored content. Developing an easily configurable multiplexing system solved the problem of detecting tailored web content. In this solution, a custom proxy receives the initial request from a client, duplicating and modifying it in many ways to change the browser, operating system, and location-based client fingerprint. All of the requests with various client fingerprints are simultaneously sent to the server. As the responses are received back at the proxy, they are aggregated and analyzed against the original response. The results of the analysis are then sent to the user along with the original response. This process allowed the proxy to detect tailored content that was previously undetectable through casual browsing. Theoretical and empirical analysis was performed to ensure the multiplexing proxy detected tailored content at an acceptable false alarm rate. Additionally, the tool was analyzed for its ability to provide utility to open source analysts, cyber analysts, and reverse engineers. The results showed that the proxy is an essential, scalable tool that provides capabilities that were not previously available.

Este estudo teve como objetivos: analisar as propriedades psicométricas dos instrumentos de avaliação de qualidade de vida WHOQOL-bref e SF-36 aplicados a pacientes adultos após a internação em Unidades de Terapia Intensiva e a seus familiares e, avaliar a concordância entre pacientes e familiares como seus substitutos. A amostra foi composta por 71 pares paciente-famíliar. A confiabilidade foi avaliada pela consistência interna através do Coeficiente Alfa de Cronbach. A validade convergente foi avaliada através das correlações interdomínios dos instrumentos e a validade divergente pelas correlações entre os domínios e o número de comorbidades através da Correlação de Spearman. A concordância entre os pares foi verificada pelo Coeficiente de Correlação Intraclasse e pela estatística kappa ponderado. Os resultados mostraram que o SF-36 quanto à confiabilidade apresenta valores aceitáveis (0,70) para a maioria dos domínios tanto para pacientes como para os familiares. Quanto ao WHOQOL-bref o coeficiente foi inferior a 0,70 para todos os domínios, em ambos os casos. A maioria das correlações interdomínios do SF-36 foram positivas e significativas para pacientes e familiares. O WHOQOL-bref quando aplicado aos pacientes apresentou correlações interdomínios positivas e significativas, mas o mesmo não ocorreu com os familiares. As correlações entre os domínios e número de comorbidades, tanto para o SF-36 e o WHOQOL–bref não foram significativas. A concordância entre os pares foi melhor quando o familiar foi o pai ou a mãe, filho e cônjuge, nessa ordem. Domínios e itens que avaliam condições objetivas são os que apresentam valores de concordância mais elevados entre os pares. O SF-36 apresentou maior número de concordâncias moderadas. O domínio Aspectos Físicos do SF-36 foi o que apresentou concordância substancial para todos os familiares. O domínio Físico do WHOQOL-bref apresentou concordância moderada para a maioria dos familiares. Para o SF-36, a concordância foi melhor quando os pacientes tinham duas ou mais comorbidades, Para o WHOQOL-bref foi melhor quando o paciente tinha uma ou duas comorbidades, mas apresentou maior número de concordâncias inconsistentes. De forma geral, os domínios previstos como aqueles que avaliam construtos similares não se correlacionaram. Esses resultados confirmam que no contexto do tratamento intensivo o SF-36 é mais adequado como instrumento de avaliação de qualidade de vida relacionado à saúde. Esses achados são similares aos da literatura internacional. / This aims this study were: to analyze the psychometric properties of the instruments for the evaluation of Quality of Life WHOQOL-bref and Medical Outcomes Study 36-Item Short Form Health Survey (SF-36) applied to adult patients after discharged from Intensive Care Units and their families and to evaluate the agreement between patients and their families as proxies. The sample consisted of 71 patient-family pairs. The internal consistency reliability was evaluated by the Cronbach’s Alfa Coefficient. The convergent validity was evaluated by the inter-domain correlations of the instruments and a divergent validity was evaluated by Spearman correlation between domains and number of comorbidities. Intraclass Correlation Coefficient and weighted kappa were used to analise the agreement between the pairs. Cronbach’s Alpha Coefficient was acceptable (0.70) for the majority of SF-36 domains for patients and their families. For the WHOQOL-bref, the coefficients were below 0, 70 for all domains in both cases. The majority of inter-domains correlation of SF-36 for patients and proxies were positive and significant. WHOQOL-bref inter-domain correlations were positive and significant when applied to the patients but not for the families. For the correlations between domains and number of comorbidities, the majority of SF-36 and WHOQOL-bref domains did not correlate for either the patients or their families. The divergent validity was not supported in both instruments. Agreement between the pairs was better when the relatives were the parents or sons. Domains and items that evaluated objective conditions presented much higher values of agreement between the pairs. The SF-36, showed a larger number of domains with moderate agreement. The Physical Role domains of SF-36 were what showed a substantial agreement for all of the families. The Physical domain of WHOQOL-bref, showed moderate agreement between each of the family members. The agreement SF-36, was better when the patients had 2 or more comorbidities, regarding the WHOQOL-bref, it was better when a patiente had 1 or 2 comorbities, however it showed a greater number of inconsistent agreements. In general, domains hypothesized to measure similar constructs do not correlated. These results confirm that the SF-36 is more suitable for the evaluation of quality of life in the intensive care context. These findings are similar to from international literature.

With the amount of users on the web steadily increasing websites must at times endure heavy loads and risk grinding to a halt beneath the flood of visitors. One solution to this problem is by using HTTP reverse proxy caching, which acts as an intermediate between web application and user. Content from the application is stored and passed on, avoiding the need for the application produce it anew for every request. One popular application designed solely for this task is Varnish; another interesting application for the task is Nginx which is primarily designed as a web server. This thesis compares the performance of the two applications in terms of number of requests served in relation to response time, as well as system load and free memory. With both applications using their default configuration, the experiments find that Nginx performs better in the majority of tests performed. The difference is however very slightly in tests with low request rate.

Abstract The thesis is focused on the reconstruction of long-term cosmic ray variability using proxy data. The 11-year solar cycle in production/deposition rates of cosmogenic nuclides ¹⁰Be and ¹⁴C has been modelled for the conditions of grand minima and maxima of solar activity (namely, Maunder Minimum and Grand Modern Maximum). The result shows that contrary to the observed strongly suppressed amplitude of the solar cycle in sunspots during Maunder Minimum relatively to Grand Modern Maximum, the cosmic ray proxies have the comparable amplitudes during the two periods. This phenomenon is caused by the nonlinear relation between solar activity and production of cosmogenic nuclides. In addition to well-established proxies of cosmic rays, nitrate in polar ice has been recently proposed as a new proxy for the long-term variability of galactic cosmic rays. The thesis contains two tests of its applicability for this purpose with TALDICE and EPICA-Dome C ice core data from Central Antarctica. The results support the proposal for the multimillennial time scales. Lunar samples acquired during the Apollo missions are important data for estimating the averaged energy spectra of galactic cosmic rays and solar energetic particles at the Earth’s orbit. The development in modelling of the interaction between energetic particles and matter makes it necessary to revise the earlier results. Because of that, new production rates of ¹⁰Be and ¹⁴C in lunar samples by galactic cosmic rays and solar energetic particles have been computed. New accurate cosmic ray reconstructions from natural archives containing cosmogenic nuclides use sophisticated climatic models requiring yield functions of the nuclides with high altitude resolution. These functions have been computed for ⁷Be, ¹⁰Be, ¹⁴C, ²²Na, and ³⁶Cl in the Earth’s atmosphere. Overall, the major purpose of the studies presented in the thesis is to increase the quality of reconstructions of the long-term cosmic ray variability for better understanding of the solar and heliospheric physics. / Original papers The original publications are not included in the electronic version of the dissertation. Poluianov, S. V., Usoskin, I. G., &amp; Kovaltsov, G. A. (2014). Cosmogenic Isotope Variability During the Maunder Minimum: Normal 11-year Cycles Are Expected. Solar Physics, 289(12), 4701–4709. https://doi.org/10.1007/s11207-014-0587-6 Poluianov, S., Traversi, R., &amp; Usoskin, I. (2014). Cosmogenic production and climate contributions to nitrate record in the TALDICE Antarctic ice core. Journal of Atmospheric and Solar-Terrestrial Physics, 121, 50–58. https://doi.org/10.1016/j.jastp.2014.09.011 Poluianov, S., Artamonov, A., Kovaltsov, G., &amp; Usoskin, I. (2015). Energetic particles in lunar rocks: Production of cosmogenic isotopes. Proceedings of Science, 30-July-2015, art. no. 051 . Traversi, R., Becagli, S., Poluianov, S., Severi, M., Solanki, S. K., Usoskin, I. G., &amp; Udisti, R. (2016). The Laschamp geomagnetic excursion featured in nitrate record from EPICA-Dome C ice core. Scientific Reports, 6(1). https://doi.org/10.1038/srep20235 Poluianov, S. V., Kovaltsov, G. A., Mishev, A. L., &amp; Usoskin, I. G. (2016). Production of cosmogenic isotopes 7Be, 10Be, 14C, 22Na, and 36Cl in the atmosphere: Altitudinal profiles of yield functions. Journal of Geophysical Research: Atmospheres, 121(13), 8125–8136. https://doi.org/10.1002/2016jd025034

Este estudo teve como objetivos: analisar as propriedades psicométricas dos instrumentos de avaliação de qualidade de vida WHOQOL-bref e SF-36 aplicados a pacientes adultos após a internação em Unidades de Terapia Intensiva e a seus familiares e, avaliar a concordância entre pacientes e familiares como seus substitutos. A amostra foi composta por 71 pares paciente-famíliar. A confiabilidade foi avaliada pela consistência interna através do Coeficiente Alfa de Cronbach. A validade convergente foi avaliada através das correlações interdomínios dos instrumentos e a validade divergente pelas correlações entre os domínios e o número de comorbidades através da Correlação de Spearman. A concordância entre os pares foi verificada pelo Coeficiente de Correlação Intraclasse e pela estatística kappa ponderado. Os resultados mostraram que o SF-36 quanto à confiabilidade apresenta valores aceitáveis (0,70) para a maioria dos domínios tanto para pacientes como para os familiares. Quanto ao WHOQOL-bref o coeficiente foi inferior a 0,70 para todos os domínios, em ambos os casos. A maioria das correlações interdomínios do SF-36 foram positivas e significativas para pacientes e familiares. O WHOQOL-bref quando aplicado aos pacientes apresentou correlações interdomínios positivas e significativas, mas o mesmo não ocorreu com os familiares. As correlações entre os domínios e número de comorbidades, tanto para o SF-36 e o WHOQOL–bref não foram significativas. A concordância entre os pares foi melhor quando o familiar foi o pai ou a mãe, filho e cônjuge, nessa ordem. Domínios e itens que avaliam condições objetivas são os que apresentam valores de concordância mais elevados entre os pares. O SF-36 apresentou maior número de concordâncias moderadas. O domínio Aspectos Físicos do SF-36 foi o que apresentou concordância substancial para todos os familiares. O domínio Físico do WHOQOL-bref apresentou concordância moderada para a maioria dos familiares. Para o SF-36, a concordância foi melhor quando os pacientes tinham duas ou mais comorbidades, Para o WHOQOL-bref foi melhor quando o paciente tinha uma ou duas comorbidades, mas apresentou maior número de concordâncias inconsistentes. De forma geral, os domínios previstos como aqueles que avaliam construtos similares não se correlacionaram. Esses resultados confirmam que no contexto do tratamento intensivo o SF-36 é mais adequado como instrumento de avaliação de qualidade de vida relacionado à saúde. Esses achados são similares aos da literatura internacional. / This aims this study were: to analyze the psychometric properties of the instruments for the evaluation of Quality of Life WHOQOL-bref and Medical Outcomes Study 36-Item Short Form Health Survey (SF-36) applied to adult patients after discharged from Intensive Care Units and their families and to evaluate the agreement between patients and their families as proxies. The sample consisted of 71 patient-family pairs. The internal consistency reliability was evaluated by the Cronbach’s Alfa Coefficient. The convergent validity was evaluated by the inter-domain correlations of the instruments and a divergent validity was evaluated by Spearman correlation between domains and number of comorbidities. Intraclass Correlation Coefficient and weighted kappa were used to analise the agreement between the pairs. Cronbach’s Alpha Coefficient was acceptable (0.70) for the majority of SF-36 domains for patients and their families. For the WHOQOL-bref, the coefficients were below 0, 70 for all domains in both cases. The majority of inter-domains correlation of SF-36 for patients and proxies were positive and significant. WHOQOL-bref inter-domain correlations were positive and significant when applied to the patients but not for the families. For the correlations between domains and number of comorbidities, the majority of SF-36 and WHOQOL-bref domains did not correlate for either the patients or their families. The divergent validity was not supported in both instruments. Agreement between the pairs was better when the relatives were the parents or sons. Domains and items that evaluated objective conditions presented much higher values of agreement between the pairs. The SF-36, showed a larger number of domains with moderate agreement. The Physical Role domains of SF-36 were what showed a substantial agreement for all of the families. The Physical domain of WHOQOL-bref, showed moderate agreement between each of the family members. The agreement SF-36, was better when the patients had 2 or more comorbidities, regarding the WHOQOL-bref, it was better when a patiente had 1 or 2 comorbities, however it showed a greater number of inconsistent agreements. In general, domains hypothesized to measure similar constructs do not correlated. These results confirm that the SF-36 is more suitable for the evaluation of quality of life in the intensive care context. These findings are similar to from international literature.