Non-Destructive Determination of the Structure and Composition of Glazes by Raman Spectroscopy

The utility of Raman spectroscopy as a non-destructive technique for the characterization of glassy (alumino)silicates (modern or ancient glazes and glasses) is demonstrated. The addition of fluxing ions breaks the Si–O linkages and the degree of (de)polymerization determines the relative intensity of the Si–O bending and stretching modes and hence the degree of polymerization could be classified. The analysis can be used to predict the processing temperature of glasses. Bending ( Q ^{' n} ) and stretching ( Qⁿ ) spectral components assigned to isolated ( Q ⁰ or SiO₄), and more or less connected SiO₄ vibrational units with one, two three/four bridging oxygen allow more precise analysis. The method is applied to reference modern porcelain glazes and selected ancient ceramic glazes and glasses, representative of the different production technologies used in the Asian, Islamic, and European worlds from Roman Empire to 19th century.     

Simulation of sea surface wave influence on small target detection with airborne laser depth sounding.

A theoretical model for simulation of airborne depth-sounding lidar is presented with the purpose of analyzing the influence from water surface waves on the ability to detect 1-m(3) targets placed on the sea bottom. Although water clarity is the main limitation, sea surface waves can significantly affect the detectability. The detection probability for a target at a 9-m depth can be above 90% at 1-m/s wind and below 80% at 6-m/s wind for the same water clarity. The simulation model contains both numerical and analytical components. Simulated data are compared with measured data and give realistic results for bottom depths between 3 and 10 m.     

High-end opto ASICs for DVD, data communication receivers and optical distance measurement

The designs with integrated photodiodes and low-noise amplifiers, presented in this paper, reach from DVD pickup units via high-speed glass and plastic fibre receivers to optical distance measurement. Furthermore, new developments in the fields of highly-parallel high-speed receivers for free-space optical interconnect and optical distance measurements are shown.     

A survey of multiple contractions

The AGM theory of belief contraction is extended tomultiple contraction, i.e. to contraction by a set of sentences rather than by a single sentence. There are two major variants: Inpackage contraction all the sentences must be removed from the belief set, whereas inchoice contraction it is sufficient that at least one of them is removed. Constructions of both types of multiple contraction are offered and axiomatically characterized. Neither package nor choice contraction can in general be reduced to contractions by single sentences; in the finite case choice contraction allows for reduction.     

Plastic displacement distributions of the Gaussian white noise excited elasto-plastic oscillator

Slepian model process approximate reasoning is used to obtain representative net and absolute yield displacement processes for the symmetric elasto-plastic oscillator of one degree of freedom excited by stationary Gaussian white noise. Yieldings occur in clumps with yield increments of alternating sign. Distributions are obtained in closed analytical form for the first yielding in a clump, the subsequent yieldings, and the accumulated net and absolute yielding from the entire clump. Moreover distributions of clump durations as well as interclump durations are obtained. All distribution parameters are theoretically calculated, that is, no parameters are obtained from estimation using simulated data. Extensive comparisons with simulated histograms show excellent fits. Also comparisons with published predictions from diffusion theory (Fokker-Planck equation based on the stochastic averaging method) show interesting features and good agreement. Finally an approximate general formula is given for the distribution of the time to the first passage of any given level of net or absolute yielding. This formula is a generalization of a corresponding formula valid for any compound Poisson process of finite second moments.     

Cognitive predictors of incident Alzheimer's disease: A prospective longitudinal study.

The present study examined whether cognitive variables measured at baseline could predict incident cases of Alzheimer's disease (AD) after a 3-year follow-up period. Twenty-six incident AD adults and 179 very old (M?=?83.5 years) adults without dementia participated in a population-based study. Cognitive performance was indexed by the Mini-Mental State Examination (MMSE) and multiple indices of memory and visuospatial and verbal performance. A logistic regression analysis that controlled for age, gender, and education indicated that MMSE scores were reliable indicators of who would develop AD. In addition, recall of organizable words, recognition of faces, and letter fluency were reliable predictors of subsequent dementia status after differences in MMSE performance were partialed out. Thus, although the MMSE is useful in predicting dementia, there is an additional advantage of assessing specific indices of cognitive functioning. Further, supportive episodic memory tasks may be more salient predictors of incident AD than tasks that offer less supportive encoding or retrieval conditions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Changes of disjunctively closed bases

An operator of contraction for a belief set (a theory) can be obtained by assigning to it a belief base and an operator of partial meet contraction for that base. It is argued that closure of the base under disjunction is an intuitively reasonable condition. Axiomatic characterizations are given of the contractions of belief sets that can be generated by (various types of) partial meet contraction on disjunctively closed bases. The corresponding revision operators are also characterized. Finally, some results are reported on operations on bases that are closed under material implication.I would like to thank Hans Rott and two anonymous referees for valuable comments and the Swedish Council for Research in the Humanities and Social Sciences for financial support.     

Physical datarepresentation in a multiprocessor database machine

By using a multiprocessor to implement the lowest level of a relational database we want to achieve fast execution of database operations such as join, find, and update. But the potential speed improvements provided by a multiprocessor can only be achieved if one can construct algorithms and corresponding physical data representations that can utilize the potential. By choosing a particular representation, the grid file, and analyzing its behaviour, we want to point out the difficulties encountered in trying to achieve speed improvements from a multiprocessor.     

Calculation of Decomposition Products from Components of Gunpowder by using ReaxFF Reactive Force Field Molecular Dynamics and Thermodynamic Calculations of Equilibrium Composition

The major combustion products from munitions containing nitro‐based propellants are water, carbon monoxide, carbon dioxide, hydrogen, and nitrogen. In addition, compounds including hydrogen cyanide, ammonia, methane, nitrogen oxides, benzene, acrylonitrile, toluene, furan, aromatic amines, benzopyrene, and various polycyclic aromatic hydrocarbons are detected in minor concentrations. The literature shows that the thermodynamic prediction of the major decomposition products agrees fairly well with the measurements. However, poor agreement is found for the minor species. We have studied the thermal decomposition products of the main gunpowder ingredients. Each of the components nitrocellulose, nitroglycerine, and the nitrate ester stabilizers diphenylamine and ethyl centralite were thermally decomposed with ReaxFF reactive force field molecular dynamics and equilibrium thermodynamics. The molecular dynamics results for the major decomposition products from nitrocellulose were partly consistent with measurements. Compared to the thermodynamic calculations, the molecular dynamics simulations agreed considerably better with experimental results for minor species like hydrogen cyanide. The nitrate ester stabilizers are the main sources for ammonia and aromatic combustion products, whereas hydrogen cyanide is produced from nitrocellulose as well as from the stabilizers when gunpowder is combusted.     

A simple method for weight estimation of whole herring (Clupea harengus) using planar X-ray imaging

Fish weight is one of the key parameters used in commercial sorting of fresh fish. The capability of on-line and accurate estimation of the weight of each individual fish has a direct impact on profitability for the fish processors. Planar X-ray images of whole herring (n=16) were taken using a commercial medical X-ray apparatus. The integral intensity of all pixels in each image was calculated and correlated with the weight of the respective fish producing a linear relationship with a high correlation factor (R2=0.992) and a calculated mean prediction error of 2.5%. Planar X-ray imaging combined with simple image processing was successfully used to predict weight of whole herring. The technique has a potential to be used industrially for on-line weight estimation in sorting/grading systems.