679 research outputs found
Dissolution Power, Confidence Votes, and Policymaking in Parliamentary Democracies
There is striking variation across parliamentary democracies in the power of prime ministers to employ two prominent procedures to resolve legislative conflict: the vote of confidence and the dissolution of parliament. While previous contributions in comparative politics have investigated each of these two fundamental institutions in isolation, I develop a simple unified model to unbundle how this richer variety of institutional configurations shapes political bargaining over policy. The analysis clarifies that the effects of the confidence vote and dissolution power interact. As a consequence, there can be a non-monotonic effect of increasing prime ministers’ formal power on their ability to shape the policy compromise. Counterintuitively, introducing dissolution power makes the prime minister worse off under some conditions. These results suggest new directions for empirical research on the consequences of parliamentary institutions for legislative politics and policy. They also lay analytical foundations for explaining institutional variation and reforms
Kernel-Level Interception and Applications on Mobile Devices
The techniques of kernel-level system call interception are well known today for many different operating systems. This work starts with transferring these technique to the Windows CE type of operating systems. Afterwards, two current problems are solved. The first solution uses the technique for dynamic malware analysis with a sandbox approach, extending previous solutions in terms of effectiveness. The second solution enhances the expressiveness of security policies by implementing the concept of a reference monitor on the operating system level. Windows CE based devices are now enabled to enforce sophisticated security policies without the need to change the underlying operating system
Electoral Reform and Trade-Offs in Representation
We examine the effect of electoral institutions on two important features of representation that are often studied separately: policy responsiveness and the quality of legislators. Theoretically, we show that while a proportional electoral system is better than a majoritarian one at representing popular preferences in some contexts, this advantage can come at the price of undermining the selection of good politicians. To empirically assess the relevance of this trade-off, we analyze an unusually controlled electoral reform in Switzerland early in the twentieth century. To account for endogeneity, we exploit variation in the intensive margin of the reform, which introduced proportional representation, based on administrative constraints and data on voter preferences. A difference-in-difference analysis finds that higher reform intensity increases the policy congruence between legislators and the electorate and reduces legislative effort. Contemporary evidence from the European Parliament supports this conclusion
Infrared regulators and SCETII
We consider matching from SCETI, which includes ultrasoft and collinear
particles, onto SCETII with soft and collinear particles at one loop. Keeping
the external fermions off their mass shell does not regulate all IR divergences
in both theories. We give a new prescription to regulate infrared divergences
in SCET. Using this regulator, we show that soft and collinear modes in SCETII
are sufficient to reproduce all the infrared divergences of SCETI. We explain
the relationship between IR regulators and an additional mode proposed for
SCETII.Comment: 9 pages. Added discussion about relationship between IR regulators
and messenger mode
Sociodemographic and psychological correlates of compliance with the Covid-19 public health measures in France
The COVID-19 disease was first identified in Wuhan, China, in December 2019, having since spread rapidly across the world. The infection and mortality rates of the disease have forced governments to implement a wave of public health measures. Depending on the context, these range from the implementation of simple hygienic rules to measures such as social distancing or lockdowns that cause major disruptions in citizens’ daily lives. The success of these crucial public health measures rests on the public's willingness to comply. However, individual differences in following the official public health recommendations for stopping the spread of COVID-19 have not yet to our knowledge been assessed. This study aims to fill this gap by assessing the sociodemographic and psychological correlates of implementing public health recommendations that aim to halt the COVID-19 pandemic. We investigate these associations in the context of France, one of the countries that has been most severely affected by the pandemic, and which ended up under a nationwide lockdown on March 17. In the next sections we describe our theoretical expectations over the associations between sociodemographics, personality, ideology, and emotions with abiding by the COVID-19 public health measures. We then test these hypotheses using data from the French Election Study
Interactive volume visualization with WebGl
Web-based applications have become increasingly popular in many areas and advances in web-based 3D graphics were made accordingly. In this context, we present a web based implementation of volume rendering using the relatively new WebGL API for interactive 3D graphics. An overview of the theoretical background of volume rendering as well as of the common approaches for a GPU implementation is given, followed by detailed description of our implementation with WebGL. Afterwards the implementation of advanced features is covered, before a short introduction to X3DOM, as a possible alternative for web based volume visualization, is given. It is the aim of this work to incorporate both basic and advanced methods of volume rendering and to achieve interactive framerates with WebGL, using the power of client-side graphics hardware. With regard to that, the result of our implementation is discussed by evaluating its performance and by comparing it to an alternative solution. Finally, we draw a conclusion of our work and point out possible future work and improvements
Security of Smartphones at the Dawn of their Ubiquitousness
The importance of researching in the field of smartphone security is substantiated in the increasing number of smartphones, which are expected to outnumber common computers in the future. Despite their increasing importance, it is unclear today if mobile malware will play the same role for mobile devices as for common computers today. Therefore, this thesis contributes to defining and structuring the field mobile device security with special concern on smartphones and on the operational side of security, i.e., with mobile malware as the main attacker model. Additionally, it wants to give an understanding of the shifting boundaries of the attack surface in this emerging research field. The first three chapters introduce and structure the research field with the main goal of showing what has to be defended against today. Besides introducing related work they structure mobile device attack vectors with regard to mobile malicious software and they structure the topic of mobile malicious software itself with regard to its portability. The technical contributions of this thesis are in Chapters 5 to 8, classified according to the location of the investigation (on the device, in the network, distributed in device and network). Located in the device is MobileSandbox, a software for dynamic malware analysis. As another device-centric contribution we investigate on the efforts that have to be taken to develop an autonomously spreading smartphone worm. The results of these investigations are used to show that device-centric parts are necessary for smartphone security. Additionally, we propose a novel device-centric security mechanism that aims at reducing the attack surface of mobile devices to mobile malware. The network-centric investigations show the possibilities that a mobile network operator can use in its own mobile network for protecting the mobile devices of its clients. We simulate the effectiveness of different security mechanisms. Finally, the distributed investigations show the feasibility of distributed computation algorithms with security modules. We give prototypic implementations of protocols for secure multiparty computation as a modularized version with failure detector and consensus algorithms, and for fair exchange with guardian angels
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