Penalty interference of nonlinear intra-channel effects and PMD inultra high-speed TDM systems

Penalty interference of nonlinear propagation impairments and polarisation mode dispersion (PMD) caused signal distortions is experimentally investigated     

13 Gb/s Si-bipolar AGC amplifier IC with high gain and wide dynamicrange for optical-fiber receivers

A complete linear automatic-gain-control (AGC) amplifier for a 10 Gb/s optical-fiber link was integrated on a single chip, using a Si-bipolar production technology with f_T≈22 GHz. It is characterized by a high gain of 37 dB, linear operation over a wide input dynamic range of 47 dB, a maximum data rate of 13 Gb/s, and a gain-independent 3-dB cut off frequency of 10 GHz. The circuit consumes 850 mW at a single supply voltage of -6.5 V. It can be operated in both a single-ended and differential mode. A novel 50-Ω input matching circuit with only small return loss is used. Two separate output buffers with a constant output voltage swing of 500 mV_p-p allow splitting up the output signal without use of external components     

Formal program construction by transformations-computer-aided,intuition-guided programming

Formal program construction by transformations is a method of software development in which a program is derived from a formal problem specification by manageable, controlled transformation steps which guarantee that the final product meets the initial specification. This methodology has been investigated in the Munich project CIP (computer-aided intuition-guided programming). The research includes the design of a wide-spectrum language specifically tailored to the needs of transformational programming, the construction of a transformation system to support the methodology, and the study of transformation rules and other methodological issues. Particular emphasis has been laid on developing a sound theoretical basis for the overall approach     

Experiences with Electronic Health Records

The healthcare system in Denmark is well known for its high level of IT support and interoperability. The Danish healthcare system integrates several central technological solutions across hospital information and electronic medical record systems throughout Denmark. Important business drivers for this high level of interoperability include unique citizen ID numbers and a publicly funded healthcare system in which hospital reimbursements are based on electronic submissions of diagnosis and procedure codes to a central register.     

Assessing channel rolling on a 450 mill

A method of assessing roller grooving for channel rolling is proposed, in which the channel shape is taken into account by means of matrix characteristics. The influence of the channel shape on the rolling force and energy is considered. The relations derived allow the load on the rolling cells to be judged on the basis of the matrix characteristics.     

Melanocortin receptor 1 (MC1R) mutations and coat color in pigs

The melanocortin receptor 1 (MC1R) plays a central role in regulation of eumelanin (black/brown) and phaeomelanin (red/yellow) synthesis within the mammalian melanocyte and is encoded by the classical Extension (E) coat color locus. Sequence analysis of MC1R from seven porcine breeds revealed a total of four allelic variants corresponding to five different E alleles. The European wild boar possessed a unique MC1R allele that we believe is required for the expression of a wild-type coat color. Two different MC1R alleles were associated with the dominant black color in pigs. MC1R*2 was found in European Large Black and Chinese Meishan pigs and exhibited two missense mutations compared with the wild-type sequence. Comparative data strongly suggest that one of these, L99P, may form a constitutively active receptor. MC1R*3 was associated with the black color in the Hampshire breed and involved a single missense mutation D121N. This same MC1R variant was also associated with EP, which results in black spots on a white or red background. Two different missense mutations were identified in recessive red (e/e) animals. One of these, A240T, occurs at a highly conserved position, making it a strong candidate for disruption of receptor function.     

Calculation of magnetic shielding of a substation at powerfrequency using FEM

The finite element method (FEM) is used for analyzing the shielding effectiveness of an eddy current shield applied to a 10/0.4 kV substation. The influence of the shield extension is studied, and a calculated magnetic field attenuation of 30 dB is obtained for a 5 mm aluminum shield applied on the ceiling and the walls. With a 3D model, the eddy current distribution in the shield is studied, giving guidance for door positioning. Here, the insertion of a door in the shielded wall off the paths of the main eddy currents is found to create only a locally elevated magnetic field. With a simplified 2D model, the influence of shield conductivity is also analyzed. An increase of the conductivity over that of aluminum here gives a limited shielding improvement     

Hybrid modelling of inhomogeneous transformer winding for very fasttransient overvoltage studies

This paper presents a novel approach for the modelling of transformer windings, which is valid in the frequency range of 10 kHz to a few MHz. It is a hybrid model; coil-by-coil detailed plus inter-coil black box model. The parameter estimation of the detailed model and the synthesis of the black box model is based on frequency domain measurements. The technique is applied to a high-voltage transformer winding. The comparison of the measurements and the frequency domain simulation of the model with EMTP confirms the validity and accuracy of the model for the intended frequency range. Experiments in the frequency range of several MHz reveal that remarkable overvoltages appear at the connecting point of the inverted and interleaved part of this winding. It is shown that the reason of the VFTO (very fast transient overvoltage) in the MHz range is the inhomogeneity of the winding parts     

Easy mass spectrometry for metabolomics and quality control of vegetable and animal fats

Easy ambient sonic spray ionization (EASI), a novel desorption/ionization technique for ambient mass spectrometry analysis, is shown to permit the characterization of different types of vegetable and animal fats. The taxonomic markers of the oils, mainly fatty acids and phenols, are extracted with methanol/water (1:1) solution and made alkaline with NH₄OH, then placed and dried on the surface of a glass tip and directly analyzed by EASI‐MS in the negative‐ion mode. EASI provides a supersonic cloud of charged droplets that causes efficient desorption and ionization of the oil markers directly from the surface of the glass tip. As proof‐of‐principle cases, EASI(?)‐MS was applied to genuine samples of olive oil, hazelnut oil, soybean oil, grape seed oil, canola oil, butter, and lard. Characteristic metabolomics EASI(?)‐MS profiles of fatty acids and eventually phenols were obtained.