Feature-Aware Verification

A software product line is a set of software products that are distinguished in terms of features (i.e., end-user--visible units of behavior). Feature interactions ---situations in which the combination of features leads to emergent and possibly critical behavior--- are a major source of failures in software product lines. We explore how feature-aware verification can improve the automatic detection of feature interactions in software product lines. Feature-aware verification uses product-line verification techniques and supports the specification of feature properties along with the features in separate and composable units. It integrates the technique of variability encoding to verify a product line without generating and checking a possibly exponential number of feature combinations. We developed the tool suite SPLverifier for feature-aware verification, which is based on standard model-checking technology. We applied it to an e-mail system that incorporates domain knowledge of AT&T. We found that feature interactions can be detected automatically based on specifications that have only feature-local knowledge, and that variability encoding significantly improves the verification performance when proving the absence of interactions.Comment: 12 pages, 9 figures, 1 tabl

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A chloride-based chemical-vapor-deposition (CVD) process has been successfully used to grow very high quality 3C-SiC epitaxial layers on on-axis α-SiC substrates. An accurate process parameters study was performed testing the effect of temperature, surface preparation, precursor ratios, nitrogen addition, and substrate polytype and polarity. The 3C layers deposited showed to be largely single-domain material of very high purity and of excellent electrical characteristics. A growth rate of up to 10 μm/h and a low background doping enable deposition of epitaxial layers suitable for MOSFET devices

Putting it all together : formal verification of the VAMP

In this thesis we describe the formal verification of a cache memory interface and its integration into a microprocessor called VAMP. The cache memory interface and the VAMP are modeled on the gate level and verified against their respective specifications, i.e., a dual-ported memory for the cache memory interface and the programmer\u27;s model of the VAMP. The cache memory interface features separate instruction and data caches with write back policy for the data cache; the caches are connected to a unified physical memory accesses via a bus protocol with bursts. The VAMP is an out-of-order 32 bit RISC CPU with DLX instruction set, fully IEEE-compliant floating point units, and a memory unit with a cache memory interface. The VAMP also supports precise interrupts. The formal verification of the out-of-order algorithm and the floating point units of the VAMP is not subject of this thesis; we \u27;only\u27; put all the different party together to an overall correctness proof.In dieser Arbeit beschreiben wir die formale Verifikation eines Cache Memory Interfaces und dessen Integration in einen Mikroprozessor, den VAMP. Das Cache Memory Interface und der VAMP werden auf der Gatterebene modelliert und gegen ihre Spezifikation verifiziert, also einen Speicher mit zwei Zugriffsports für das Cache Memory Interface und das Programmiermodell des VAMP. Das Cache Memory Interface besteht aus getrennten Instruktions- und Daten-Caches mit write-back Policy für den Daten-Cache. Die Caches sind mit einem vereinten physikalischen Speicher verbunden, auf den mittels eines Busprotokolls mit Bursts zugegriffen wird. Der VAMP ist eine out-of-order 32-bit RISC CPU mit DLX-Instruktionssatz, vollständig IEEE-konformen Fließkommaeinheiten und einer Speicher-Einheit mit einem Cache Memory Interface. Der VAMP unterstützt auch präzise Interrupts. Die formale Verifikation des out-of-order Algorithmus und der Fließkommaeinheiten des VAMP ist nicht Gegenstand dieser Arbeit; wir setzen lediglich die verschiedenen Teile zusammen zu einem Gesamt-Korrektheitsbeweis

Revealing Hidden Self-financed Wash Trading in Non-Fungible-Token Markets

Pricing and sales volumes for non-fungible tokens (NFTs) have seen a meteoric rise and fall in recent years. Partially because of a loss of faith in the true values of NFT assets. Wash trading has emerged to artificially inflate asset prices and trading volumes of NFTs. This not only endangers the integrity of NFT markets but also raises doubts about the authenticity of NFT values. Previous research has identified wash trading actors with techniques such as cyclical trading. Many of the presented techniques, however, can be associated with flaws concerning obviousness or feasibility with constrained capital resources. We propose a method to identify a more intricate and concealed form of wash trading called self-financed trading. Our approach identifies suspicious activities by tracking cash and asset flows between blockchain addresses. This enables us to reveal networks of wash trading designed to reap marketplace rewards or insinuate demand to drive up prices

a multidimensional Scale Based on a Three-Country Study

We develop and test a multidimensional scale measuring national identification. Drawing on the extant literature on nations and national identity, we propose national identification as an understanding of how individuals subjectively and dynamically relate to different characteristics of nations that we operationalize as the dimensions of symbolic, civic, and solidary identification. We discuss the development of a number of questionnaire items representing each of these dimensions and report results of various validity and reliability tests using data from three surveys we conducted in England, Germany, and Poland. Results in general confirm the three-dimensional structure of the overall construct while at the same time suggesting country-specific adaptations to the scale

National identification: a multidimensional scale based on a three‐country study

"We develop and test a multidimensional scale measuring national identification. Drawing on the extant literature on nations and national identity, we propose national identification as an understanding of how individuals subjectively and dynamically relate to different characteristics of nations that we operationalize as the dimensions of symbolic, civic, and solidary identification. We discuss the development of a number of questionnaire items representing each of these dimensions and report results of various validity and reliability tests using data from three surveys we conducted in England, Germany, and Poland. Results in general confirm the three-dimensional structure of the overall construct while at the same time suggesting country-specific adaptations to the scale." (author's abstract

Bell violation with entangled photons, free of the fair-sampling assumption

The violation of a Bell inequality is an experimental observation that forces one to abandon a local realistic worldview, namely, one in which physical properties are (probabilistically) defined prior to and independent of measurement and no physical influence can propagate faster than the speed of light. All such experimental violations require additional assumptions depending on their specific construction making them vulnerable to so-called "loopholes." Here, we use photons and high-efficiency superconducting detectors to violate a Bell inequality closing the fair-sampling loophole, i.e. without assuming that the sample of measured photons accurately represents the entire ensemble. Additionally, we demonstrate that our setup can realize one-sided device-independent quantum key distribution on both sides. This represents a significant advance relevant to both fundamental tests and promising quantum applications

The mechanochemical Scholl reaction – a solvent-free and versatile graphitization tool

Herein, we report on the mechanochemical Scholl reaction of dendritic oligophenylene precursors to produce benchmark nanographenes such as hexa-peri-hexabenzocoronene (HBC), triangular shaped C60 and expanded C222 under solvent-free conditions. The solvent-free approach overcomes the bottleneck of solubility limitation in this well-known and powerful reaction. The mechanochemical approach allows tracking the reaction process by in situ pressure measurements. The quality of produced nanographenes has been confirmed by MALDI-TOF mass spectrometry and UV-Vis absorption spectroscopy. This approach paves the way towards gram scale and environmentally benign synthesis of extended nanographenes and possibly graphene nanoribbons suitable for application in carbon based electronics or energy applications

Großflächige Abscheidung von Graphen - Ein wichtiger Schritt für neuartige Bauelemente

Das wachsende Interesse an Graphen beruht auf seiner unverwechselbaren Bandstruktur und seinen damit zusammenhängenden herausragenden physikalischen Eigenschaften. Es wird daher weltweit nach einem Verfahren gesucht, Graphen großflächig und mit hoher Qualität abzuscheiden. In einer an der TH Wildau [FH] speziell für diese Aufgabe konzipierten Reaktionskammer wurde die Herstellung mittels chemischer Gasphasenabscheidung auf katalytischen Metalloberflächen für verschiedene Parameter studiert und deren Verträglichkeit mit der CMOS -Technologie untersucht. Die ersten Tests erfolgten auf Nickel, da hier eine im Volumen stattfindende katalytische Reaktion einsetzt. In weiteren Schritten fiel die Wahl auf Kupfer, da hier die Reaktion an der Oberfläche stattfindet und daher ein stabilerer Prozess realisiert werden konnte. Die Qualitätsprüfung der erzeugten Schichten erfolgte mittels Ramanspektrometrie

Effects of ceftiofur treatment on the susceptibility of commensal porcine E.coli – comparison between treated and untreated animals housed in the same stable

Background Healthy farm animals have been found to act as a reservoir of extended-spectrum β-lactamase (ESBL)-producing Escherichia coli (E. coli). Therefore, the objective of the study was to determine the input of antimicrobial active ceftiofur metabolites in the stable via faeces and urine after intramuscular administration of the drug to pigs and the elucidation of the Escherichia coli ESBL resistance pattern of treated and untreated pigs housed in the same barn during therapy. Methods For determination of the minimal inhibitory concentration (MIC) the method of microdilutionaccording to the recommended procedure of the Clinical and Laboratory Standards Institute was used. Inaddition to that, a qualitative determination was performed by agar dilution. Unsusceptible E. coli speciesselected via agar dilution with cefotaxime were confirmed by MALDI-TOF and ESBL encoding genes wereidentified by PCR. The amounts of ceftiofur measured as desfuroylceftiofur (DFC) in the different probes (plasma, urine, faeces and dust) were analysed by UPLC-MS/MS. Results In a first experiment two groups of pigs (6 animals per group) were housed in the same barn in two separated boxes. One group (group B) were treated with ceftiofur according to the licence (3 mg/kg administered intramuscularly (i.m.) on three consecutive days, day 1–3). During a second treatment period (day 29–31) an increased rate of ESBL resistant E. coli was detectable in these treated pigs and in the air of the stable. Moreover, the second group of animals (group A) formerly untreated but housed for the whole period in the same stable as the treated animals revealed increased resistance rates during their first treatment (day 45–47) with ceftiofur. In order to investigate the environmental input of ceftiofur during therapy and to simulate oral uptake of ceftiofur residues from the air of the stable a second set of experiments were performed. Pigs (6 animals) were treated with an interval of 2 weeks for 3 days with different doses of ceftiofur (3 mg/kg, 1 mg/kg and 0.3 mg/kg i.m.) as well as with 3 mg/kg per os) and the renal and biliary excretion of ceftiofur as its active metabolite were measured in comparison to the plasma levels. In addition to that, probes of the sedimentation dust and the air of the stable were analysed for drug residues. Conclusion The present study shows that treatment of several animals in a stable with ceftiofur influences the resistance pattern of intestinal Escherichia coli of the treated as well as untreated animals housed in the same stable. During therapy with the drug which was administered by injection according to the licence we detected nameable amounts of ceftiofur and its active metabolites in the dust and air of the stable