Completeness Thresholds for Memory Safety: Early Preliminary Report

In this early preliminary report on an ongoing project, we present -- to the best of our knowledge -- the first study of completeness thresholds for memory safety proofs. Specifically we consider heap-manipulating programs that iterate over arrays without allocating or freeing memory. We present the first notion of completeness thresholds for program verification which reduce unbounded memory safety proofs to bounded ones. Moreover, we present some preliminary ideas on how completeness thresholds can be computed for concrete programs.Comment: 20 pages, early preliminary repor

Semi-Automated Modular Formal Verification of Critical Software: Liveness and Completeness Thresholds

In this dissertation we describe two contributions to the state of the art in reasoning about liveness and safety, respectively. Programs for multiprocessor machines commonly perform busy waiting for synchronization. We propose the first separation logic for modularly verifying termination of such programs under fair scheduling. Our logic requires the proof author to associate a ghost signal with each busy-waiting loop and allows such loops to iterate while their corresponding signal $s$ is not set. The proof author further has to define a well-founded order on signals and to prove that if the looping thread holds an obligation to set a signal $s'$, then $s'$ is ordered above $s$. By using conventional shared state invariants to associate the state of ghost signals with the state of data structures, programs busy-waiting for arbitrary conditions over arbitrary data structures can be verified. Moreover, we present the first study of completeness thresholds for bounded memory safety proofs. Specifically, we consider heap-manipulating programs that iterate over arrays without allocating or freeing memory. In this setting, we present the first notion of completeness thresholds for program verification which reduce unbounded memory safety proofs to bounded ones. Furthermore, we demonstrate that we can characterise completeness thresholds for simple classes of array traversing programs. Finally, we suggest avenues of research to scale this technique theoretically, i.e., to larger classes of programs (heap manipulation, tree-like data structures), and practically by highlighting automation opportunities.Comment: PhD Dissertation, 226 pages (68 pages body + 141 pages appendix

Towards Social CRM – Scoping the Concept and Guiding Research

Web 2.0 and Social Media (SoMe) provide new opportunities for collaboration and co-value creation which supports a customer-centric management. Social Customer Relationship Management (SCRM) addresses these opportunities and aims at a high stakeholder engagement as a means to establish mutually beneficial relationships. At present, scholars attempt to comprehend what constitutes SCRM. This paper reviews state-of-the-art scholarly literature to provide a consolidated view on the current SCRM knowledge base. It reveals concurrent opinions, diverging perceptions and future directions for research along the dimensions SCRM definitions, objectives and approaches. We conclude that SCRM as a novel concept requires transformational efforts among all organizational parts. Approaches towards SCRM align on organizational determinants, CRM processes, the customer relationship lifecycle or develop conceptual models. We propose that research further explore this domain to progress the understanding of SCRM as basis for corresponding frameworks

Strong Einstein-Podolsky-Rosen entanglement from a single squeezed light source

Einstein-Podolsky-Rosen (EPR) entanglement is a criterion that is more demanding than just certifying entanglement. We theoretically and experimentally analyze the low resource generation of bi-partite continuous variable entanglement, as realized by mixing a squeezed mode with a vacuum mode at a balanced beam splitter, i.e. the generation of so-called vacuum-class entanglement. We find that in order to observe EPR entanglement the total optical loss must be smaller than 33.3 %. However, arbitrary strong EPR entanglement is generally possible with this scheme. We realize continuous wave squeezed light at 1550 nm with up to 9.9 dB of non-classical noise reduction, which is the highest value at a telecom wavelength so far. Using two phase controlled balanced homodyne detectors we observe an EPR co-variance product of 0.502 \pm 0.006 < 1, where 1 is the critical value. We discuss the feasibility of strong Gaussian entanglement and its application for quantum key distribution in a short-distance fiber network.Comment: 4 pages, 4 figure

Digital Nudging: Altering User Behavior in Digital Environments

Individuals make increasingly more decisions on screens, such as those on websites or mobile apps. However, the nature of screens and the vast amount of information available online make individuals particularly prone to deficient decisions. Digital nudging is an approach based on insights from behavioral economics that applies user interface (UI) design elements to affect the choices of users in digital environments. UI design elements include graphic design, specific content, wording or small features. To date, little is known about the psychological mechanisms that underlie digital nudging. To address this research gap, we conducted a systematic literature review and provide a comprehensive overview of relevant psychological effects and exemplary nudges in the physical and digital sphere. These insights serve as a valuable basis for researchers and practitioners that aim to study or design information systems and interventions that assist user decision making on screens