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In recent years, library systems have evolved from simple electronic catalogues to extensive document sources. Progress in storage media, database and wide area networking technologies allow access to documents in their original form. Besides “modern” documents, which are often created and distributed in electronic exchange formats, huge amounts of ancient, paper based literature which are valuable...
First S-questionnaires are introduced as mechanical devices which permit the representation of recursively definable families of information structures by means of sets of sequences of non-negative integers. The subclass of L-questionnaires is then defined enabling: i) a bijection between such a family F and the set ℕ of non-negative integers ii) the construction of an operator admitting exactly the...
Let be associated to each element N of the set of the normal forms of the λ-κ-β calculus and to each integer r > 0 the semi but non - decidable domain D [N,r] $$ \subseteq $$ r onto which N, considered as partial map ping r→, is total (that is the computation starting from NX1 ... Xr where N ∈ and X1, ..., xr ∈ D [N,r] and evolging through a β -reduction algorithm terminates). The decidability...
Currently four complete setups have been assembled and used for soft- and firmware development in order to improve stability and functionality. Noise and performance measurements were made in order to characterize the hardware. A full article with detailed descriptions about the demonstrator hardware and measurements will be submitted to the Transaction on Nuclear Science (TNS).
The TileCal Demonstrator is a prototype for a future upgrade to the ATLAS hadron calorimeter when the Large Hadron Collider increases its luminosity in year 2023 (HL-LHC). It will be used for functionality and performance tests. The Demonstrator has 48 channels of upgraded readout and digitizing electronics and a new digital trigger capability, but stays backwards compatible with the present detector...
A potential upgrade for the front-end electronics, signal digitization, and data acquisition system of the ATLAS central hadron calorimeter for the High Luminosity Large Hadron Collider (HL-LHC) is described. A Demonstrator is being built to readout a slice of the TileCal detector with this system. The on-detector electronics includes up to 48 analog Front-end Boards for processing the PMT signals,...
During 2014, upgraded-demonstrator electronics will be installed in a Tile calorimeter drawer to obtain long term experience with the redundant electronics proposed for a full upgrade scheduled for 2022.
We have developed a slice prototype of the full TileCal readout chain based on prototype modules and off-the-shelf components. As different module prototypes are developed and become available they can replace earlier prototypes or emulators in the chain. Due to its modular and flexible structure, the prototype can adapt to changing requirements. This will allow most of the final functionality to...
The European XFEL project requires a high-speed and high-quality clock and trigger distribution system. The main clock frequency is 1.3 GHz and needs to be distributed over several kilometers of distance. At each destination several clock frequencies needs to be derived and triggers needs to be decoded. All clocks and triggers must be phase stable throughout the entire system. However, every component,...
Based on the assumption that the parameter can be measured in real time, we propose a model predictive control (MPC) method for linear-parameter varying (LPV) systems subject to possibly asymmetric constraints which adopts the analogous framework of terminal control law, terminal set and terminal penalty of nonlinear model predictive control. The optimization problem is formulated as a convex optimization...
The mechanical properties of polymer encapsulating materials change considerably when packages are exposed to elevated temperatures for longer times. Here we report a systematic study on the change in viscoelastic properties of a commercial molding compound which is stored at 175°C for periods of time ranging up to 4 weeks. It is shown that instead of the expected degradation, the modulus and the...
The European X-ray Free Electron Laser experiment (XFEL) [1][2] at DESY in Hamburg will start in a few years and make possible new, impressive experiments. The whole system will require a very precise clock and trigger distribution, synchronous to the 1.3 GHz system RF-frequency, over distances of more than 3.4 km. Stockholm University in collaboration with DESY has developed a prototype for the timing...
An electronic device cannot perform its designed functions until it is packaged such that it is interconnected with the rest of the system and protected. As an encapsulation material, thermosetting polymers are widely used. It is well known that properties of polymer-based composites like molding compounds are highly affected by the influence of temperature, relative humidity and degree of conversion...
Homogeneous-in-the-state bilinear systems, appended by an additive disturbance, appear both from the discretization of some partial differential equations and from the bilinearization of certain nonlinear systems. They often have large state vectors that can be cumbersome for simulation and control system design. Our aim is to define a method, invariant to time transformations, for finding a reduced-order...
Thermosetting polymers are widely used in electronic industry as encapsulants of electronic devices. It is well known that properties of polymers and polymer-based composites like molding compounds are highly dependent on conditions like: temperature, time, humidity, degree of cure etc. These effects are investigated extensively in the past. Surprisingly, the effect of postcure and thermal aging on...
The European XFEL project [1] requires a high-speed and high-quality clock and trigger distribution system. The main system frequency will be 1.3 GHz which will be distributed over a distance of more than 3.4 km, and all triggers will be related to it. All the clocks must have adjustable phases so that they can be kept in phase throughout the entire system. Distributing signals over such a long distance...
The European XFEL project requires a high-speed, very precise clock and timing distribution over large distances. A prototype system which fulfils current requirements that uses high-end components has just been completed and is being tested. However, the system is quite complicated and the boards are very complex, being designed using the small micro-TCA form factor. A way to simplify the system,...
A method extending the functionality of silicon photomultipliers (SiPMs) has been developed. It enables the use of SiPMs for quantifying high radiation fluxes in current mode as well as in pulse mode measurements for counting and characterizing individual gamma-ray or X-ray photons when coupled to scintillators. This opens new possibilities for multimodal medical imaging by providing the means for...
Embedded devices for control and monitoring are becoming more powerful as technology evolves. It is common that these embedded devices are communicating through a local area network with other, sometimes more powerful, nodes for receiving and distributing commands and data gathering. This distributed system can then be connected to other systems over the Internet for data exchange, remote control...
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