Damage visualization and deformation measurement in glass laminates during projectile penetration

Transparent armor consists of glass-polymer laminates in most cases. The formation and propagation of damage in the different glass layers has a strong influence on the ballistic resistance of such laminates. In order to clarify the course of events during projectile penetration, an experimental technique was developed, which allows visualizing the onset and propagation of damage in each single layer of the laminate. A telecentric objective lens was used together with a microsecond video camera that allows recording 100 frames at a maximum rate of I MHz in a backlit photography set-up. With this technique, the damage evolution could be visualized in glass laminates consisting of four glass layers with lateral dimensions 500 mm x 500 mm. Damage evolution was recorded during penetration of 7.62 mm AP projectiles with tungsten carbide core and a total mass of 11.1 g in the impact velocity range from 800 to 880 rn/s. In order to measure the deformation of single glass plates within the laminates, a piece of reflecting tape was attached to the corresponding glass plate, and photonic Doppler velocimetry （PDV） was applied. With the photonic Doppler velocimeter, an infrared laser is used to illuminate an object to be measured and the Doppler-shifted light is superimposed to a reference light beam at the detector. The simultaneous visualization and PDV measurement of the glass deformation allow determining the deformation at the time of the onset of fracture. The analysis of the experimental data was supported by numerical simulations, using the AUTODYN commercial hydro-code.     

Automatic pronunciation scoring of words and sentences independent from the non-native’s first language

This paper describes an approach for automatic scoring of pronunciation quality for non-native speech. It is applicable regardless of the foreign language student’s mother tongue. Sentences and words are considered as scoring units. Additionally, mispronunciation and phoneme confusion statistics for the target language phoneme set are derived from human annotations and word level scoring results using a Markov chain model of mispronunciation detection. The proposed methods can be employed for building a part of the scoring module of a system for computer assisted pronunciation training (CAPT). Methods from pattern and speech recognition are applied to develop appropriate feature sets for sentence and word level scoring. Besides features well-known from and approved in previous research, e.g. phoneme accuracy, posterior score, duration score and recognition accuracy, new features such as high-level phoneme confidence measures are identified. The proposed method is evaluated with native English speech, non-native English speech from German, French, Japanese, Indonesian and Chinese adults and non-native speech from German school children. The speech data are annotated with tags for mispronounced words and sentence level ratings by native English teachers. Experimental results show, that the reliability of automatic sentence level scoring by the system is almost as high as the average human evaluator. Furthermore, a good performance for detecting mispronounced words is achieved. In a validation experiment, it could also be verified, that the system gives the highest pronunciation quality scores to 90% of native speakers’ utterances. Automatic error diagnosis based on a automatically derived phoneme mispronunciation statistic showed reasonable results for five non-native speaker groups. The statistics can be exploited in order to provide the non-native feedback on mispronounced phonemes.     

A Survey on Gradient‐Domain Rendering

Monte Carlo methods for physically‐based light transport simulation are broadly adopted in the feature film production, animation and visual effects industries. These methods, however, often result in noisy images and have slow convergence. As such, improving the convergence of Monte Carlo rendering remains an important open problem. Gradient‐domain light transport is a recent family of techniques that can accelerate Monte Carlo rendering by up to an order of magnitude, leveraging a gradient‐based estimation and a reformulation of the rendering problem as an image reconstruction. This state of the art report comprehensively frames the fundamentals of gradient‐domain rendering, as well as the pragmatic details behind practical gradient‐domain uniand bidirectional path tracing and photon density estimation algorithms. Moreover, we discuss the various image reconstruction schemes that are crucial to accurate and stable gradient‐domain rendering. Finally, we benchmark various gradient‐domain techniques against the state‐of‐the‐art in denoising methods before discussing open problems.     

Combined biological–chemical (Ozone) treatment of wastewaters containing chloroguaiacols

Biological degradation of chloroguaiacols contained in sulphite pulp chlorine bleaching wastewater was studied in four parallel biological fluidised bed reactor systems—one single aerobic, one single anaerobic and two combined anaerobic–aerobic reactors. At low loading rates, trichloroguaiacols were removed nearly quantitatively. 4,5-Dichloroguaiacol was only partly removed. At high loading rates the anaerobic–aerobic recycle reactor removed individual guaiacols more than the other reactors. Only 4,5,6-trichloroguaiacol was removed best by the anaerobic–aerobic reactors in series. Even mixed culture biofilms adapted during several years of continuous operation did not satisfactorily remove these compounds. Synthetic wastewater, containing chlorinated guaiacols, treated with ozone produced formate and oxalate and quantitatively inorganic chloride. Combined ozonation–biotreatment in two reactors in series as well as in a recycle system allowed complete removal of all individual chlorinated guaiacols (< 1 μmol m^?3 remained). The efficiency of non-purgable organic carbon removal could be increased from ≤0.55 to about 4 mol carbon mol^?1 ozone by combination of ozonation with biotreatment. Simultaneously, the efficiency of removal of chlorinated guaiacols was increased by a factor of 10, which is essential for industrial application.     

Fractionation of potato juice proteins into acid-soluble and acid-coagulable fractions

Potato juice proteins were fractionated by acidification to pH 3 into acid-coagulable and acid-soluble fractions. Both fractions are heterogeneous. They differ in molecular weight, conformation in solution and composition of amino acids. The acid-coagulable fraction consists of units of molecular weight between 32,000 and 87,000, while the acid-soluble fraction consists of units of molecular weight between 17,000 and 27,000. Circular dichroism measurements show that the acid-coagulable fraction is in helical and beta conformations whilst, for the acid-soluble fraction, a substantial contribution of the random conformation is observed. The acid-coagulable fraction has a higher content of methionine than the acid-soluble fraction. It is shown that this type of fractionation is more meaningful than fractionation in terms of albumins and globulins by solubility in water or dilute salt solutions.     

Engineering yeast alcohol dehydrogenase. Replacing Trp54 by Leu broadens substrate specificity

Analysis of a crystal structure of alcohol dehydrogenase (Adh)from horse liver suggests that Trp54 in the homologous yeastalcohol dehydrogenase prevents the yeast enzyme from efficientlycatalysing the oxidation of long-chain primary alcohols withbranching at the 4 position (e.g. 4-methyl-1-pentanol, cinnamylalcohol). This residue has been altered to Leu by site-directedmutagenesis. The alteration yields an enzyme that serves asan effective catalyst for both longer straight-chain primaryalcohols and branched chain alcohols.     

Atmospheric spouted bed combustion: The role of hydrodynamics in emissions generation and control

Recent studies have reaffirmed the utility of spouted beds as potential combustion devices for a variety of fuels: solid, liquid and gaseous fuels (Arbib and Levy, 1982; Weinberg et al., 1988; Zhao et al., 1987; Altwicker et al., 1989; Altwicker and Lin, 1991; Altwicker et al., 1993; Konduri et al., 1994). In this study, the role of annulus residence time on the performance of such a spouted bed combustor is investigated. The experiments presented here show that fluid hydrodynamics in the annulus of a spouted bed combustor can significantly influence the overall performance; changing the residence time in the annulus significantly affects the concentrations of products due to incomplete combustion at the exit of the combustor. The annular residence time is varied by changing the shape of the bottom of the reactor, by introducing a draft tube and by changing the bed heighn. Propane is used as the fuel and sand as the bed medium. Inferences from the combustion results are supported by pressure and temperature profiles. A streamtube model (Lim and Mathur, 1976) was used to obtain an estimate of the residence time in the annulus. It is concluded that the flame processes taking place at the top of the annulus play a critical role in the emission generation and that more information is needed to understand the annulus-flame.     

Impact of partial alcohol reduction in Syrah wine on perceived complexity and temporality of sensations and link with preference

Complexity is often stated as a mark of wine quality but there are no quantitative data supporting this assumption. The effect of partial alcohol reduction on the perceived complexity, temporality of sensations and liking of a Syrah wine was investigated.An Australian Syrah wine was partially dealcoholized using the reverse osmosis technique to obtain five wines with different alcohol content (13.5–8%). 71 French wine consumers evaluated their liking for these wines as well as the perceived intensity of overall complexity and eight items reported to be linked to perceived complexity in wine (familiarity, persistence, etc.) using continuous scales, anchored with pictures (Medel, Viala, Meillon, Urbano, & Schlich, 2009). In addition, eight trained panelists described temporality of sensations in the same wines with the Temporal Dominance of Sensations (TDS) method. The overall complexity scale was well understood by consumers with a significant discrimination of wines according to their alcohol content. Wines with higher alcohol content were perceived as more complex, persistent, strong and with many aromas. They were associated to more complex temporal sensory profiles, with many sensations that blend in-mouth along time.