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By considering the tiling of an N-board (a linear array of N square cells of unit width) with new types of tile that we refer to as combs, we give a combinatorial interpretation of the product of two consecutive generalized Fibonacci numbers $ s_n $ s n (where $ s_{n}=\sum _{i=1}^q v_i s_{n-m_i} $ s n = ∑ i = 1 q v i s n − m i , $ s_0=1 $ s 0 = 1 , $ s_{n \lt 0}=0 $ s n < 0 = 0 , where $ v_i $ v i and $ m_i $ m i are positive integers and $ m_1 \lt \cdots \lt m_q $ m 1 < ⋯ < m q ) each raised to an arbitrary non-negative integer power. A $ (w,g;m) $ (w , g ; m) -comb is a tile composed of m rectangular sub-tiles of dimensions $ w\times 1 $ w × 1 separated by gaps of width g. The interpretation is used to give combinatorial proof of new convolution-type identities relating $ s_n^2 $ s n 2 for the cases q = 2, $ v_i=1 $ v i = 1 , $ m_1=M $ m 1 = M , $ m_2=m+1 $ m 2 = m + 1 for M = 0, m to the permanent of a (0,1) Toeplitz matrix with 3 nonzero diagonals which are $ -2 $ − 2 , M−1, and m above the leading diagonal. When m = 1, these identities reduce to ones connecting the Padovan and Narayana's cows numbers. [ABSTRACT FROM AUTHOR]

Summarizes the conference proceedings, asserting that two fundamental questions were addressed: "How can international cohesion be achieved without also reducing diversity?" and "How can collateral damage to local higher education systems be avoided?" (EV)

Noting that the least responsive fields of higher education to virtual provision seem to be the humanities, asserts that as humanists come to see that education has been overly teacher-oriented, they may become increasingly receptive to virtual teaching and learning. (EV)

All dielectric self-supporting (ADSS) fiber optic cable is known to have a limited service lifetime in some environments when installed near high voltage transmission lines. Dry band arcing can cause deterioration of the cable jacket and thus has been identified as a contributing factor to this short lifetime for some cables. It has been shown that wet contamination on the jacket of the ADSS cable increases the likelihood of dry band arcing, and hence, is a predictor of short service life. In this work, a portable transducer for measuring wet contamination levels (e.g., electrical resistance per meter) on the jacket of an ADSS cable has been designed, constructed, and calibrated in a high voltage environment. It is simple to operate and can be used while the transmission line is energized. More specifically, it has been shown effective when used on an ADSS cable in electric fields comparable to those near 500-kV transmission lines. Index Terms--Optical fiber cables, optical fiber protective covering, test equipment.

The amount of power flowing through a high-voltage transmission line is proportional to its voltage and the current flowing through it. To increase power flow without modifying the line to support increased voltage, the current must be increased. There is a limit to this, however, since increasing the current causes the conductor temperature to increase and, hence, the conductors to elongate and sag. In this paper, a method to simply and inexpensively measure the amount of conductor sag and, through simple calculation, the average conductor core temperature is described, and the results of a field test are summarized. The method involves attaching two ends of a grounded wire of high electrical resistance to an appropriate location on each of two transmission-line towers and measuring the current induced on the wire by the nearby transmission-line conductors. Information from this measurement is a critical input to any method for dynamically rating transmission lines. Index Terms--Distributed parameter circuits, electromagnetic coupling, power generation dispatch, power system monitoring, power transmission lines, transmission-line measurements.

Soil vapor extraction (SVE) to remove volatile contaminants from contaminated soil in the unsaturated zone has been successful in sand and gravel formations. In less permeable glacial till, the usefulness of SVE is unclear. Field experiments in the loam till of central Iowa were performed to determine air permeabilities. A radial and vertical, anisotropic, heterogeneous compressible-flow model coupled with an optimization routine solved the inverse problem by using vacuum pressure and flow-rate data to estimate air permeabilities. Air-permeability anisotropy was determined to be less important than depth variations. Using a four-layer description of the deposit to account for varying moisture content with depth, the average predicted air permeability varied from 4 X 10 to the -8 cm squared in the deepest layer to 1 X 10 to the -5 cm squared in the layer nearest the ground surface.

Field venting tests were conducted in alluvial sands residing between the water table and a clay layer. Flow rate, barometric pressure, and well-pressure data were recorded using pressure transmitters and a personal computer. Data was logged as frequently as every second during periods of rapid change in pressure. Tests were conducted at various extraction rates. The data from several tests were analyzed concurrently by normalizing the well pressures with respect to extraction rate. The normalized pressures vary logarithmically with time and fall on one line allowing a single match of the Jacob approximation to all tests. Though the Jacob approximation was originally developed for hydraulic pump test analysis, it is now commonly used for venting test analysis. Only recently, however, has it been used to analyze several transient tests simultaneously. For the field venting tests conducted in the alluvial sands, the air permeability and effective porosity determined from the concurrent analysis are 8.2 x [10.sup.-7] [cm.sup.2] and 20%, respectively.

Compiler molds microcode to any architecture When using conventional compiler technology, moving an algorithm from one microarchitecture to another takes many weeks or even months. The Hilevel-C compiler, however, jointly […]