Information exchange between control centres in the West European high-voltage grid

Although each electric utility is autonomous concerning the supply of electricity within a certain area, the high-voltage grids of Western Europe are joined together into an international system. The Union for Coordination of Generation and Transport of Electrical Energy in Western Europe (UCPTE) is responsible for coordinating the operation of this interconnected system. The advantages of this system, which include an optimal energy exchange between all partners and increased effectiveness through common operation and coordinated planning, are discussed. Coordination and execution of the system depends on an active exchange of information on an international basis, but owing to the separate development of individual utilities, a homogeneous information exchange system does not exist, despite efforts by UCPTE. The UCPTE-recommended data-transfer protocol, based on the ISO standards for open systems interconnection, is discussed.     

Experimental investigation and numerical modeling of light nonaqueous phase liquid dissolution and transport in a saturated zone of the soil

The present research aims at studying the dissolution and transport process of benzene as a light nonaqueous phase liquid (LNAPL) in saturated porous media. This process is studied under unidirectional flow at different water velocities ranging from 0.90 to 3.60 cm/h in a three-dimensional saturated sand tank (100 cm × 40 cm × 35 cm). This tank represents a laboratory-scale aquifer. The dispersion parameters of the sand tank are based on an independent tracer experiments. The experimental aquifer is simulated by developing a three-dimensional finite element numerical model. This model assumes that the dissolved concentration along the LNAPL-water interface is equal to the solubility concentration. The numerical model results overpredict the experimental within factor 1.6 and 2.29 at depths of 1 cm and 3 cm, respectively, during eight days. The correlation coefficient is ranging from 0.8485 to 0.9986. The time invariant average mass transfer coefficient is determined at each interstitial velocity. The values are ranged from 0.016 to 0.061 cm/h (i.e. increased with velocity toward a limiting value). For a circular benzene pool, two linear relationships are found; the first between the overall Sherwood number (Sh(e)(*)) with average Peclet number in x-direction (Pe(x(e))(*)); and the second between the overall Sherwood number (Sh(e)(*)) with average Peclet number in y-direction (Pe(y(e))(*)).     

Effect of structural parameters of porous yarns and fabric on air permeability and moisture transfer of double-face woven fabrics

In this study, effect of fabric structural parameters of double-face woven fabrics including kind of porous yarn namely micro-porous yarn and hollow yarn, hole size of hollow yarn, percentage of these yarns in double-face woven fabric structure, and finally weft density on air permeability and moisture transfer of woven fabrics was evaluated. These yarns were produced by using water-soluble continuous polyvinyl alcohol filaments as core part for hollow yarns and as doubling yarn in micro-porous yarn. Results revealed the effect of kind of porous yarn, hole size of hollow yarn, and weft density on air permeability and moisture transfer of woven fabrics. The percentage of porous yarns as weft did not show obvious trend. Analysis of variance was used to study the effect of these variables on air permeability and moisture transfer of double-face woven fabrics statistically.     

The TMS34010: an embedded microprocessor

The authors discuss the TMS34010, a high-performance 32-bit microprocessor with special instructions and hardware for handling the bit-field data and address manipulations often associated with computer graphics. They give a history of embedded microprocessors and examine the wide range of processors and applications covered by that term. They provide an overview of the internal architecture of the TMS34010 and discuss the choice of feature set in its design. Although it is aimed at graphics systems, the processor's large address reach, bit-field processing, and DRAM (dynamic random-access memory) interface make it suitable for many other embedded processing applications.<>     

Photocatalytic generation of useful hydrocarbons and hydrogen from acetic acid in the presence of lanthanide modified TiO2

Pure and Ln³⁺ modified TiO₂ photocatalysts (Ln³⁺ = Eu³⁺ or Sm³⁺ ions) synthesized by a sol-gel method as well as commercially available P25 were applied for photocatalytic generation of useful hydrocarbons and hydrogen from acetic acid. Structure and surface properties of the photocatalysts were characterized by XRD, UV-vis/DR, FT-IR and N₂ adsorption-desorption measurements. The main gaseous products of CH₃COOH decomposition were CH₄ and CO₂. Trace amounts of C₂H₆ and H₂ were also detected in the reaction mixture. Moreover, it was observed that the quantities of all identified gases increased with elongation of irradiation time. The most active photocatalysts towards CH₄ and H₂ generation were Ln³⁺/TiO₂ containing 0.05 mol % of Sm and Eu, respectively. The results revealed that the Ln³⁺ modification can improve the effectiveness of the photocatalysts compared to pure and commercially available TiO₂ provided that a proper amount of modifying ions is used.     

Requirements for a VLSI Graphics Processor

This article will discuss issues that must be considered in the design of a VLSI (very large scale integration) 32-bit microprocessor specialized for graphics applications. With a properly chosen architecture, a single-chip graphics processor should provide a cost-effective means for achieving high performance in color bit-mapped graphics displays for PCs and workstations. The goal in selecting an architecture is to reduce the components required for a medium-to high-resolution display so they fit easily on a single, small, printed-circuit card. At the same time the processing speed must result in screen updates that occur without perceptible delay. These improvements should enable bit-mapped graphics displays to replace the text-only displays that have seen wide-spread use in cost-sensitive applications.     

Investigation of the hydrogen production of a laser FUSION driver thorium breeder using various coolants

In this present work, hydrogen production and neutronic calculations of a Laser Inertial Confinement Fusion Fission Energy (LIFE) driven thorium breeder using various coolants have been investigated. In the neutronic calculations for fusion driver power of 500 MW_th has been examined with MCNP code. The 95 vol% Flibe or natural lithium 5 vol% TRISO coated ThC fuels have used in the neutronic calculations. Tritium breeding ratio (TBR) has been calculated as 1.08 and 1.19, respectively, for Flibe and natural lithium coolants. The energy multiplication values have been computed as 3.17 and 1.62, respectively, for these coolants. The burnup values with flibe and natural lithium have been obtained as 6 GWd/tM and 22 GWd/tM over 11 and 23 years, respectively. Also, the hydrogen production of a laser fusion driver thorium breeder using steam methane reforming (SMR), high temperature electrolysis (HTE) and sulfur-iodine (S–I) thermochemical water splitting processes have been performed. The highest hydrogen production values with flibe coolant of SMR method have been obtained as ~200 kg/s over 11 years.