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This paper presents the design and implementation of three System-on-Chip (SoC) cores, which implement the Digital Signal Processing (DSP) functions: Finite Impulse Response (FIR) filter, Infinite Impulse Response (IIR) filter and Fast Fourier Transform (FFT). The FIR-filter core is based on the symmetrical realization form, the IIRfilter core is based on the Second Order Sections (SOS) architecture and the FFT core is based on the Radix 22 Single Delay Feedback (R22SDF) architecture. The three cores are compatible with the Wishbone SoC bus, and they were described using generic and structural VHDL. In-system hardware verification was performed by using an OpenRisc-based SoC synthesized on an Altera FPGA. Tests showed that the designed DSP cores are suitable for building SoC based on the OpenRisc processor and the Wishbone bus.

A formal set of design decisions can aid in using oscillation-based test (OBT) for analog subsystems in SoCs. The goal is to offer designers testing options that do not have significant area overhead, performance degradation, or test time. This work shows that OBT is a potential candidate for IP providers to use in combination with functional test techniques. We have shown how to modify the basic concept of OBT to come up with a practical method. Using our approach, designers can use OBT to pave the way for future developments in SoC testing, and it is simple to extend this idea to BIST. ; European Union 26354

Earth's climate varies continuously across space and time, but humankind has witnessed only a small snapshot of its entire history, and instrumentally documented it for a mere 200 years. Our knowledge of past climate changes is therefore almost exclusively based on indirect proxy data, i.e. on indicators which are sensitive to changes in climatic variables and stored in environmental archives. Extracting the data from these archives allows retrieval of the information from earlier times. Obtaining accurate proxy information is a key means to test model predictions of the past climate, and only after such validation can the models be used to reliably forecast future changes in our warming world. The polar ice sheets of Greenland and Antarctica are one major climate archive, which record information about local air temperatures by means of the isotopic composition of the water molecules embedded in the ice. However, this temperature proxy is, as any indirect climate data, not a perfect recorder of past climatic variations. Apart from…

Earth's climate varies continuously across space and time, but humankind has witnessed only a small snapshot of its entire history, and instrumentally documented it for a mere 200 years. Our knowledge of past climate changes is therefore almost exclusively based on indirect proxy data, i.e. on indicators which are sensitive to changes in climatic variables and stored in environmental archives. Extracting the data from these archives allows retrieval of the information from earlier times. Obtaining accurate proxy information is a key means to test model predictions of the past climate, and only after such validation can the models be used to reliably forecast future changes in our warming world. The polar ice sheets of Greenland and Antarctica are one major climate archive, which record information about local air temperatures by means of the isotopic composition of the water molecules embedded in the ice. However, this temperature proxy is, as any indirect climate data, not a perfect recorder of past climatic variations. Apart from…

Very few white-collar criminals are detected. They are able to commit and conceal their fraud to benefit their organization or themselves, and continue in their privileged professional positions as members of the elite in society. When rumors of misconduct and crime occur, white-collar offenders are often so powerful that nothing happens to them. Some are too powerful to detect, investigate, prosecute, and jail.Whistleblowers play an important role in detection. They detect crime signals and send messages to people who can do something about the situation. They may report internally to executives or auditors, or they may send messages externally to journalists or public authorities.After discussion of white-collar fraud in the perspective of convenience theory, this book moves into its core of fraud signal detection, detailing the key terms signal strength, signal alertness, pattern recognition, and personal experience. The book then presents four case studies where whistleblowers reported fraud suspicions. After whistleblowing, fraud examiners were hired to reconstruct past events in private internal investigations.

Einige Steuerungen von Werkzeugmaschinen gestatten es, durch NC (Numerical Control)-Kernerweiterungen auf Signale und Daten in Echtzeit zuzugreifen und diese zu manipulieren. Die Entwicklung der NC-Kernerweiterung ist jedoch geprägt von einer fehleranfälligen Phase der Programmierung. Es wird eine Methode vorgestellt, die einen Ansatz der modellgetriebenen Softwareentwicklung beschreibt, um schnell und zuverlässig NC-Kernerweiterungen am Beispiel der Regelung von Vorschubachsen zu entwickeln.
 
Some control systems of machine tools provide the opportunity to access signals and data by NC-core extensions in real time. Typical for the development of NC-core extensions is an error-prone phase of programming. This article presents a method which uses an approach of model-based software development to quickly generate reliable NC-core extensions. The method is exemplified by position control on feed drives.

Recent paleomagnetic studies of two Main Group pallasites, the Imilac and Esquel, have found evidence for a strong, late-stage magnetic field on the parent body. It has been hypothesized that this magnetic field was generated by a core dynamo, driven by compositional convection during core solidification. Cooling models suggest that the onset of core solidification occurred ∼200 Ma after planetary accretion. Prior to core solidification, a core dynamo may have been generated by thermal convection; however a thermal dynamo is predicted to be short-lived, with a duration of ∼10 Ma to ∼40 Ma after planetary accretion. These models predict, therefore, a period of quiescence between the thermally driven dynamo and the compositionally driven dynamo, when no core dynamo should be active. To test this hypothesis, we have measured the magnetic remanence recorded by the Marjalahti and Brenham pallasites, which based on cooling-rate data locked in any magnetic field signals present ∼95 Ma to ∼135 Ma after planetary accretion, before core solidification began. The cloudy zone, a region of nanoscale tetrataenite islands within a Fe-rich matrix was imaged using X-ray photoemission electron microscopy. The recovered distribution of magnetisation within the cloudy zone suggests that the Marjalahti and Brenham experienced a very weak magnetic field, which may have been induced by a crustal remanence, consistent with the predicted lack of an active core dynamo at this time. We show that the transition from a quiescent period to an active, compositionally driven dynamo has a distinctive paleomagnetic signature, which may be a crucial tool for constraining the time of core solidification on differentiated bodies, including Earth. ; We acknowledge the Helmholtz-Zentrum Berlin for the use of the synchrotron radiation beam time at beamline UE49 of BESSY II. The research leading to these results has received funding from the European Research Council under the European Union's Seventh Framework Programme (FP/2007-2013)/ERC grant agreement numbers 320750 and 312284, and the Natural Environment Research Council. We thank the Natural History Museum, London for samples. ; This is the final version of the article. It first appeared from Elsevier via https://doi.org/10.1016/j.epsl.2016.02.037