Vienna University of Technology

About: Vienna University of Technology is a education organization based out in Vienna, Austria. It is known for research contribution in the topics: Laser & Cloud computing. The organization has 16723 authors who have published 49341 publications receiving 1302168 citations.

Climate change impacts - throwing the dice?

Abstract: Although Einstein was referring to quantum mechanics in this statement rather than to hydrology, one sometimes does wonder whether we are throwing the dice in hydrological analyses. When two experts estimate the 100-year flood in a small ungauged catchment, chances are that their estimates are very different. When two groups predict the effects of future hydrological changes on stream flow and recharge for the same catchment, the results will hardly be consistent. Yet, climate change impact analyses have become a standard method in our tool box for addressing issues that seem to be of overwhelming concern to the society today. In this paper, we argue that impact studies often tend to be overly optimistic about the reliability of their predictions, and overly pessimistic about the effects on society. Just as a medical doctor who, when in doubt, would say that his patient is going to die—to be on the safe side. We will contrast this assessment with our views on the current state of change prediction, and outline the opportunities in this exciting field of hydrologic research.

Prospex: Protocol Specification Extraction

Abstract: Protocol reverse engineering is the process of extracting application-level specifications for network protocols. Such specifications are very useful in a number of security-related contexts, for example, to perform deep packet inspection and black-box fuzzing, or to quickly understand custom botnet command and control (C\&C) channels.Since manual reverse engineering is a time-consuming and tedious process, a number of systems have been proposed that aim to automate this task. These systems either analyze network traffic directly or monitor the execution of the application that receives the protocol messages. While previous systems show that precise message formats can be extracted automatically, they do not provide a protocol specification.The reason is that they do not reverse engineer the protocol state machine.In this paper, we focus on closing this gap by presenting a system that is capable of automatically inferring state machines. This greatly enhances the results of automatic protocol reverse engineering, while further reducing the need for human interaction. We extend previous work that focuses on behavior-based message format extraction,and introduce techniques for identifying and clustering different types of messages not only based on their structure, but also according to the impact of each message on server behavior.Moreover, we present an algorithm for extracting the state machine.We have applied our techniques to a number of real-world protocols, including the command and control protocol used by a malicious bot. Our results demonstrate that we are able to extract format specifications for different types of messages and meaningful protocol state machines. We use these protocol specifications to automatically generate input for a stateful fuzzer,allowing us to discover security vulnerabilities in real-world applications.

Searches for long-lived charged particles in pp collisions at sqrt(s) = 7 and 8 TeV

Abstract: Results of searches for heavy stable charged particles produced in pp collisions at sqrt(s) = 7 and 8 TeV are presented corresponding to an integrated luminosity of 5.0 inverse femtobarns and 18.8 inverse femtobarns, respectively. Data collected with the CMS detector are used to study the momentum, energy deposition, and time-of-flight of signal candidates. Leptons with an electric charge between e/3 and 8e, as well as bound states that can undergo charge exchange with the detector material, are studied. Analysis results are presented for various combinations of signatures in the inner tracker only, inner tracker and muon detector, and muon detector only. Detector signatures utilized are long time-of-flight to the outer muon system and anomalously high (or low) energy deposition in the inner tracker. The data are consistent with the expected background, and upper limits are set on the production cross section of long-lived gluinos, scalar top quarks, and scalar tau leptons, as well as pair produced long-lived leptons. Corresponding lower mass limits, ranging up to 1322 GeV for gluinos, are the most stringent to date.

Calculation of the magnetic anisotropy with projected-augmented-wave methodology and the case study of disordered Fe 1 -x Co x alloys

Abstract: The magnetic anisotropy energy of tetragonally distorted disordered alloys Fe ${}_{1\ensuremath{-}x}{\mathrm{Co}}_{x}$ is calculated by two different virtual crystal approximation methods and an averaged supercell method within the projected-augmented-wave (PAW) methodology and the magnetic force theorem. The details of the spin-orbit coupling implementation in the PAW methodology are given. We compare our results to the recent coherent potential approximation (CPA) studies, results of full potential calculations, and to the available experiments.

Optimized IoT service placement in the fog

Abstract: The Internet of Things (IoT) leads to an ever-growing presence of ubiquitous networked computing devices in public, business, and private spaces. These devices do not simply act as sensors, but feature computational, storage, and networking resources. Being located at the edge of the network, these resources can be exploited to execute IoT applications in a distributed manner. This concept is known as fog computing. While the theoretical foundations of fog computing are already established, there is a lack of resource provisioning approaches to enable the exploitation of fog-based computational resources. To resolve this shortcoming, we present a conceptual fog computing framework. Then, we model the service placement problem for IoT applications over fog resources as an optimization problem, which explicitly considers the heterogeneity of applications and resources in terms of Quality of Service attributes. Finally, we propose a genetic algorithm as a problem resolution heuristic and show, through experiments, that the service execution can achieve a reduction of network communication delays when the genetic algorithm is used, and a better utilization of fog resources when the exact optimization method is applied.