EyeSpot: leveraging gaze to protect private text content on mobile devices from shoulder surfing

As mobile devices allow access to an increasing amount of private data, using them in public can potentially leak sensitive information through shoulder surfing. This includes personal private data (e.g., in chat conversations) and business-related content (e.g., in emails). Leaking the former might infringe on users’ privacy, while leaking the latter is considered a breach of the EU’s General Data Protection Regulation as of May 2018. This creates a need for systems that protect sensitive data in public. We introduce EyeSpot, a technique that displays content through a spot that follows the user’s gaze while hiding the rest of the screen from an observer’s view through overlaid masks. We explore different configurations for EyeSpot in a user study in terms of users’ reading speed, text comprehension, and perceived workload. While our system is a proof of concept, we identify crystallized masks as a promising design candidate for further evaluation with regard to the security of the system in a shoulder surfing scenario

Development of a Contactless Conductivity Sensor in Flowing Micro Systems for Cerium Nitrate

Impedance spectroscopy has a high potential to detect chemical reactions in flowing systems. In this work, the approach using impedance spectroscopy as a possible analytical tool for a continuous hydrothermal syntheses (CHTS) is presented. With the CHTS-process, it is possible to produce metalloxide nanoparticles with a close particle size distribution and specific surface properties. For this, it is necessary to evaluate the electrode geometry, frequency and other factors influencing the impedance with respect to concentration measurements. In case of frequency-sweep measurements possible electrode geometries for C4D-Sensors (capacitively coupled contactless conductivity detection) are evaluated. Then distinguishability and reproducibility are tested applying titration measurements to show the ability for concentration detection in constant flow systems. The possibility to measure concentration changes in flowing systems in a reproducible and fast manner as well as with high distinguishability for the test solution cerium nitrate will be presented. Furthermore, the major influencing-factors like electrode geometry, frequency etc. could be determined. It has been shown that with increasing electrode spacing and electrode width, the distinguishability of the concentrations increases and shifts them to lower frequencies

The International Authority Database

International organizations (IOs) are perceived as increasingly important, yet also severely challenged actors in world politics. How authoritative are IOs, how do they exercise authority, and how has their authority evolved over time? The International Authority Database (IAD) offers a novel measure of IO authority built from several aspects of an IO's institutional design. We provide systematic data on how IOs exercise authority across seven policy functions, using a representative sample of 34 IOs, based on coding over 200 IO bodies, and covering the period 1920-2013. Empirical applications illustrate how the IAD advances our understanding of IOs in novel and important ways

Überwachung der kontinuierlichen hydrothermalen Synthese mittels Impedanzspektroskopie

Die kontinuierliche hydrothermale Synthese (CHTS) stellt ein vielversprechendes Verfahren zur Herstellung metalloxidischer Nanopartikel dar. Das Prinzip beruht auf der Vermischung einer kalten wässrigen Metallsalzlösung mit einem nahe-/überkritischen Wasserstrom. Durch die außergewöhnlichen Eigenschaften des überkritischen Wassers kommt es zur Partikelbildung. Neben der Studie des Einflusses der Prozessparameter auf die resultierende Partikelgröße und -verteilung ist die Restkonzentration an gelöstem Metallsalz von Interesse. Diese kann mittels der Impedanzspektroskopie analysiert werden. Dazu werden an einer modifizierten CHTS-Anlage Vorversuche durchgeführt, um zukünftig die Restkonzentration direkt bestimmen zu können

Observation of universal relaxation dynamics in disordered quantum spin systems

A major goal toward understanding far-from-equilibrium dynamics of quantum many-body systems consists in finding indications of universality in the sense that the dynamics no longer depends on microscopic details of the system. We realize a large range of many-body spin systems on a Rydberg atom quantum simulator by choosing appropriate Rydberg state combinations. We use this platform to compare the magnetization relaxation dynamics of disordered Heisenberg XX-, XXZ- and Ising Hamiltonians in a scalable fashion. After appropriate rescaling of evolution time, the dynamics collapse onto a single curve. We find that the observed universal behavior is captured by theoretical models that only consider local pairs of spins. Associated to each pair is a local quasi-conserved quantity, allowing us to describe the early time dynamics of the system in terms of an integrable model similar to systems featuring prethermalization. Since the dynamics of pairs are independent of the type of Hamiltonian up to a scaling factor, this integrable model explains the observed universal relaxation dynamics of disordered Heisenberg quantum spin systems

Politische Ordnungsbildung wider Willen - ein Forschungsprogramm zu transnationalen Konflikten und Institutionen

"In diesem Discussion-paper wird das Forschungsprogramm der Abteilung 'Transnationale Konflikte und internationale Institutionen' (TKI) vorgestellt. Das Forschungsprogramm richtet den Blick auf eine Entwicklungsdynamik, die durch die Errichtung der internationalen Institutionen nach dem Zweiten Weltkrieg ausgelöst wurde und im Ergebnis zu einer politischen Ordnung jenseits des Nationalstaates in einer normativ gehaltvollen Bedeutung führen kann. Im ersten Teil des Papiers werden zunächst die Erfolge und Misserfolge internationaler Institutionen nach dem Zweiten Weltkrieg in den Blick genommen. Darauf aufbauend werden die beiden zentralen Forschungsthesen des Programms entwickelt. Der ersten These zufolge hat die Verlagerung des Regierens auf internationale Institutionen einen nicht intendierten Trend zur Supra- und Transnationalisierung der politischen Steuerung zur Folge. Die zweite These geht davon aus, dass die zunehmende Eingriffstiefe und der Bedeutungszuwachs von trans- und supranationalen Organisationen im Laufe der Zeit zu einer gesellschaftlichen Politisierung und zu Legitimationsproblemen politischer Steuerung jenseits des Nationalstaats führen. Im letzten Teil des Papiers werden schließlich die geplanten und bereits begonnenen Forschungsprojekte vorgestellt, die die beiden Thesen mit unterschiedlicher Schwerpunktsetzung überprüfen. Dabei erheben die einzelnen Projekte nicht den Anspruch, das vorliegende Forschungsprogramm als Ganzes abzubilden. Vielmehr konzentrieren sie sich auf einzelne Aspekte, die jedoch in der Summe empirisch abgestützte Aussagen zu den Kernthesen ermöglichen." (Autorenreferat)"This discussion paper introduces the new program of the research unit, 'Transnational Conflicts and International Institutions' (TKI) at the Social Science Research Center Berlin (WZB). The research program focuses on the developmental dynamics that were initiated with the creation of international institutions following the Second World War and which may lead to the establishment of a new, normatively significant political order beyond the nation-state. The first part of the paper considers the successes and failures of post-World-War-II institutions and, based on these results, develops the two core theses of the program. The first thesis is that the shift of governance and governing to international institutions results in a trend toward the transnationalization or supranationalization of policies, as an unintended side-effect. The second thesis is that the increasing depth of intervention, and the steady accumulation and concentration of power by supranational organizations will, over time, result in the politicizing of society and subsequent problems of legitimacy for forms of governance beyond the nation-state. The final part of the paper discusses the projects that have been initiated in the research unit, or are in the planning stages, each of which analyzes a different aspect of this problem in order to test our main hypotheses. The cumulative research will provide sufficient collective empirical evidence to probe our core theses." (author's abstract

Structured Biotinylated Poly(3,4-Ethylenedioxypyrrole) Electrodes for Biochemical Applications

The immobilization of biotin on transducer surfaces is a very important step for the fabrication of biosensors for many applications (immunoassay, DNA-hybridization assays, targeted imaging). Biotinylated polypyrroles have been studied and tested but gave rise to problems of polymerization and stability due to the intrinsic properties of pyrrole. As an alternative, biotinylated pyrroles were often used in a copolymerization with pyrrole or with an amphiphilic pyrrole derivative in a copolymerization to reduce the problems due to the pyrrole substitution. To find a new strategy, this paper presents the homopolymerization, instead of the use of a copolymerization, by replacing pyrrole by 3,4-ethylenedioxypyrrole bearing biotinylated substituent. We report the synthesis, characterization and electrochemical properties of two biotinylated 3,4-ethylenedioxypyrroles differing by the length of the alkyl spacer (ethyl or dodecyl) as well as the characterization of the corresponding polymer films. We successfully show, by cyclic voltammetry, that these monomers polymerize perfectly and give relatively stable polymer films. The increase of the alkyl spacer improves the polymerization and increases the polymer stability. For the first time, we also studied the surface morphology of an electrodeposited biotinylated polymer. The electrodeposition of these biotinylated derivatives gave rise to the ability to modulate the surface microstructuration, which consists of microspheres or cauliflower-like microstructures according to the length of the alkyl spacer.JRC.I.4-Nanobioscience