Impact in Scotland of UK and EC Sewage Legislation

The EC Directive (91/271/EEC) concerning urban waste water treatment has far-reaching financial and technological implications for local authorities in Scotland which are responsible for sewerage. Increased capital consent limits and additional financial assistance from central government are essential if the requirements of the legislation are to be met.
Although the Directive is welcomed in general terms, the sections of the legislation dealing with the identification of sensitive waters and the provision of primary treatment for coastal discharges to less sensitive waters are of limited environmental significance in Scotland.
The elimination of sewage sludge disposal at sea will create severe difficulties for Scottish authorities as a high percentage of sewage sludge is currently disposed of at sea. Each of the main alternative disposal options presents environmental, financial and technical problems and, in the case of incineration, the certainty of widespread unpopularity with the public.     

An evaluation of imaging spectrometry for estimating forest canopy chemistry

Abstract

High spectral resolution Airborne Imaging Spectrometer (AIS) data were acquired over 20 well-studied Wisconsin forest sites to evaluate the potential of remote sensing for estimating forest canopy chemistry. Intensive nutrient cycling research in these forests demonstrates that canopy lignin content is strongly related to measured annual nitrogen mineralization at the undisturbed sites and may serve as an accurate index for nitrogen cycling rates. Ground measurements were made of foliar biomass and canopy nitrogen and lignin content, the latter within two weeks of the AIS overflight. The spectral data were transformed using derivative techniques modified from laboratory spectroscopy. Stepwise regression assisted in determining combinations of wavelengths most highly correlated with canopy chemistry and biomass. Strong correlations between AIS data and total canopy lignin content in deciduous forests and canopy lignin concentration (total lignin/biomass) in both deciduous and coniferous stands indicate that imaging spectrometry can be used to estimate canopy lignin content and, from that, the spatial distribution of annual nitrogen mineralization rates.     

A laboratory investigation of a physical rnechanisim for the extended infrared absorption (‘red shift‘) in wheat

Laboratory spectral measurements, on the components of both greenhouse and field grown winter wheat, were performed to identify the component and its appropriate response which gave rise to the extended infrared absorption or ‘red shift’ reported by Collins. Results of this study indicated that inherent intraplant adaxial (upper) leaf reflectances were of sufficient variability to suggest that an admixture of mechanisms may have utility on identifying the booting and head emergence stages in the life cycle of wheat. The physical mechanism for the shift was found to be relatively independent of the inherent variability in leaf spectra, and to be dependent upon the difference in the mode of deposition of cuticle upon the abaxial (lower) surface relative to that of the adaxial (upper) surface, ihe position of the flag leaf, and thus the surface exposed to the incident light during heading and after emergence of the head.     

TOWARD AN ARRAY OF PHENOMENOLOGICAL IDEAL-TYPES FOR THE SOCIAL SCIENCES

Beginning with the isolation of four essentially unique mathematical intervals on a continuum, we show the process by which an array of four phenomenological ideal-types can be generated which carry rather specific analytical and administrative implications. The basic vehicle of the paper is deductive inference, employed to generate successively more specific taxonomies of system types, eventuating in the four felt to be a specific interest as real-world references for the social scientist, with empirical point included wherever they can defend the deductions.     

An assessment of OH airglow interference on the remote sensing of stratospheric HC1 via limb sounding in the near-I.R.

Chemiluminescent emission from the formation of vibrationally excited OH at an altitude of approximately 85 km presents a barrier to Earth limb measurements of near-infrared emissions originating in the stratosphere. High resolution measured spectra of OH airglow in the region of interest have not been reported, and thus it is difficult to assess its impact on moderately high resolution Earth limb spectroscopy capable of looking between strong OH lines. Low resolution rocket-borne spectrometer Earth limb measurements of OH airglow arc mathematically inverted to recover vibrational state populations that are used to simulate a higher resolution spectrum in the neighbourhood of 2843cm^-1, Implications for remote sensing HCI are presented.     

Optimal location of process measurements

The problem of optimally locating a given number of Bensors for observing a general linear distributed parameter system is considered. Measurements at the sensors are assumed to be available continuously in time, and the design criterion is minimization of a scalar measure of the covariance of the estimate error in the optimal linear filter. Necessary conditions for optimality are derived based on the formulation of a distributed parameter matrix minimum principle. A computational algorithm is developed for determining the optimum set of measurement locations. The algorithm is applied to the problem of optimally locating temperature sensors in a solid undergoing transient heat conduction.     

AUTOMATIC GENERATION OF TECHNICAL DOCUMENTATION

Natural-language generation (NLG) techniques can be used to automatically produce technical documentation from a domain knowledge base and linguistic and contextual models. We discuss this application of NLG technology from both a technical and a usefulness (costs and benefits) perspective. This discussion is based largely on our experiences with the Intelligent Documentation Advisory System (IDAS) documentation-generation project, and the reactions that various interested people from industry have had to IDAS. We hope that this summary of our experiences with IDAS and the lessons we have learned from it will be beneficial for other researchers who wish to build technical documentation-generation systems.     

Robust stability of polynomials with multilinear parameter dependence

The problem is studied of testing for stability a class of real polynomials in which the coefficients depend on a number of variable parameters in a multilinear way. We show that the testing for real unstable roots can be achieved by examining the stability of a finite number of corner polynomials (obtained by setting parameters at their extreme values), while checking for unstable complex roots normally involves examining the real solutions of up to m + 1 simultaneous polynomial equations, where m is the number of parameters. When m = 2, this is an especially simple task.     

Robust recursive identification of multidimensional linear regression models

Stochastic adaptive estimation and control algorithms involving recursive prediction estimates have guaranteed convergence rates when the noise is not ‘too’ coloured, as when a positive-real condition on the noise mode is satisfied. Moreover, the whiter the noise environment the more robust are the algorithms. This paper shows that for linear regression signal models, the suitable introduction of while noise into the estimation algorithm can make it more robust without compromising on convergence rates. Indeed, there are guaranteed attractive convergence rates independent of the process noise colour. No positive-real condition is imposed on the noise model.     

YTTRIUM ALUMINATE CERAMIC FIBERS VIA PRE-CERAMIC POLYMER AND SOL-GEL ROUTES

ABSTRACT

Yttrium aluminum garnet (YAG - Y₃Al₅O₁₂) fibers have been prepared by dry spinning solutions of yttrium and aluminum carboxylate polymers (precursor route) and by dry spinning aqueous oxide sols (sol-gel route). Fibers from aqueous diphasic gels are prepared by mixing a colloidal alumina sol containing 50-nm hydrous alumina with a colloidal yttria sol containing 10-nm yttrium oxide, using polyvinylpyrrolidone as a spinning aid. Fibers by the precursor route are made from spinnable THF solutions of yttrium isobutyrate and aluminum isobutyrate or from aqueous solutions of polymeric aluminum formate and yttrium acetate.

The isobutyrate materials decompose between 200-400^°C to an amorphous residue. Crystallization occurs abruptly between 875°C and 900^°C, forming the YAG phase directly. The formate-acetate also decomposes to amorphous residues, which form YAG at 900^°C. In the diphasic gel, YAG forms gradually between 1000 and 1200^°C, with intermediate products YAP (YalO₃ perovskite) and/or YAM (Y₄Al₂O₉ monoclinic). At 1500^°C, single phase YAG is obtained as pore-free fibers with 500 nm grains.