Dielectric features of two grades of bi‐oriented isotactic polypropylene

The dielectric properties of two grades of bi‐oriented isotactic polypropylene were studied with a variety of techniques: breakdown field measurements, dielectric spectroscopy, thermally stimulated depolarization currents (Is), and direct‐current (dc) conduction I values. Standard polypropylene (STPP) and high‐crystallinity polypropylene (HCPP) films were investigated. Measurements were carried out over a wide temperature range (?150°C/+125°C). The breakdown fields in both materials showed a very small difference. On the other hand, the dielectric losses and dc conduction I values were significantly lower in HCPP. Both materials showed a decrease in the dielectric loss versus temperature in the range 20–90°C; this is favorable for application in alternating‐current power capacitors. The analysis of the dc I value allowed us to find evidence of two main conduction mechanisms: (1) below 80°C in both materials, a hopping mechanism due to the motion of electrons occurred in the amorphous phase, and (2) above 80°C, ionic conduction occurred in HCPP, and hopping conduction occurred in STPP. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42224.     

Comparison of entropy and complexity measures for the assessment of depth of sedation

Entropy and complexity of the electroencephalogram (EEG) have recently been proposed as measures of depth of anesthesia and sedation. Using surrogate data of predefined spectrum and probability distribution we show that the various algorithms used for the calculation of entropy and complexity actually measure different properties of the signal. The tested methods, Shannon entropy (ShEn), spectral entropy, approximate entropy (ApEn), Lempel-Ziv complexity (LZC), and Higuchi fractal dimension (HFD) are then applied to the EEG signal recorded during sedation in the intensive care unit (ICU). It is shown that the applied measures behave in a different manner when compared to clinical depth of sedation score--the Ramsay score. ShEn tends to increase while the other tested measures decrease with deepening sedation. ApEn, LZC, and HFD are highly sensitive to the presence of high-frequency components in the EEG signal.     

Study and characterization of PD in impregnated polypropylenecapacitors

Measurements of partial discharge (PD) in models of impregnated polypropylene capacitors with and without specific defects have been conducted. Two different regimes of discharges (in the liquid and in gas bubbles) are illustrated. The effect of temperature on the decrease of the insulation property is underlined. Four specific defects have been artificially introduced in the test cell (poor impregnation, bad contact, fold in the polypropylene (PP) film, cavity). The relevance of parameters such as skewness and kurtosis to characterize PD distributions is discussed. New parameters based upon the mean position of the PD in the voltage phase are proposed for a better recognition of the defects inducing PD     

Effects of smoking bans on passive smoking exposure at work and at home. The European Community respiratory health survey

This longitudinal study investigated whether smoking bans influence passive smoking at work and/or at home in the same subjects. Passive smoking at work and/or at home was investigated in random population samples (European Community Respiratory Health Survey) in 1990‐1995, with follow‐up interviews in 1998‐2003 and 2010‐2014. National smoking bans were classified as partial (restricted to public workplaces) or global (extended to private workplaces). Multivariable analysis was accomplished by three‐level logistic regression models, where level‐1, level‐2, and level‐3 units were, respectively, questionnaire responses, subjects, and centers. Passive smoking at work was reported by 31.9% in 1990‐1995, 17.5% in 1998‐2003, and 2.5% in 2010‐2014. Concurrently, passive smoking at home decreased from 28.9% to 18.2% and 8.8%. When controlling for sex, age, education, smoking status, and ECHRS wave, the odds of passive smoking at work was markedly reduced after global smoking bans (OR = 0.45, 95% CI 0.25‐0.81), particularly among non‐smokers, while the protective effect of global smoking bans on passive smoking at home was only detected in non‐smokers. Smoking bans both in public and private workplaces were effective in reducing passive smoking at work in Europe. However, given the inefficacy of smoking bans in current smokers’ dwellings, better strategies are needed to avoid smoking indoors.     

Effects of iconicity and semantic relatedness on lexical access in american sign language.

Iconicity is a property that pervades the lexicon of many sign languages, including American Sign Language (ASL). Iconic signs exhibit a motivated, nonarbitrary mapping between the form of the sign and its meaning. We investigated whether iconicity enhances semantic priming effects for ASL and whether iconic signs are recognized more quickly than noniconic signs are (controlling for strength of iconicity, semantic relatedness, familiarity, and imageability). Twenty deaf signers made lexical decisions to the 2nd item of a prime–target pair. Iconic target signs were preceded by prime signs that were (a) iconic and semantically related, (b) noniconic and semantically related, or (c) semantically unrelated. In addition, a set of noniconic target signs was preceded by semantically unrelated primes. Significant facilitation was observed for target signs when they were preceded by semantically related primes. However, iconicity did not increase the priming effect (e.g., the target sign PIANO was primed equally by the iconic sign GUITAR and the noniconic sign MUSIC). In addition, iconic signs were not recognized faster or more accurately than were noniconic signs. These results confirm the existence of semantic priming for sign language and suggest that iconicity does not play a robust role in online lexical processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Charge breeding simulations for radioactive ion beam production

The charge breeding technique is used for radioactive ion beam (RIB) production in order of optimizing the re-acceleration of the radioactive element ions produced by a primary beam in a thick target. Charge breeding is achieved by means of a device capable of increasing the ion charge state from 1+ to a desired value n+. In order to get high intensity RIB, experiments with charge breeding of very high efficiency could be required. To reach this goal, the charge breeding simulation could help to optimize the high charge state production efficiency by finding more proper parameters for the radioactive 1+ ions. In this paper a device based on an electron beam ion source (EBIS) is considered. In order to study that problem, a code already developed for studying the ion selective containment in an EBIS with RF quadrupoles, BRICTEST, has been modified to simulate the ion charge state breeding rate for different 1+ ion injection conditions. Particularly, the charge breeding simulations for an EBIS with a hollow electron beam have been studied.     

Avoiding trickle-down recompilation in the Mary2 implementation

Programming languages which support separate but not independent compilation are prone to a problem called trickle-down recompilation. These languages, which include Ada, Modula and others as well as Mary2,¹ permit a compilation unit to refer at compile time to objects declared in another, imported, compilation unit. When the exporting compilation unit is recompiled for any reason, its exported interface may change, and so the importing compilation units which are the clients of that interface must be recompiled. These recompilations in turn force others, and so on Many recompilations are in fact innocuous, in that they may change the run-time behaviour of the recompiled unit but do not alter the exported interface. This paper describes the implementation of that portion of the Mary2 language system which performs just those recompilations actually necessary and avoids redundant recompilations. The methods described are applicable to the implementation of any other language which enforces version control across compilations.     

Particle-initiated breakdown in a quasi-uniform field intransformer oil

The breakdown voltage induced by single metallic cylinders of millimeter lengths in a quasi-uniform AC field are reported. A particular electrode arrangement, including forced oil circulation, has been designed in order to avoid particle ejection out of the gap. Breakdown occurred in the range 25 to 80 kV/cm depending on the particle dimensions, and always when the particle was in contact with the positive electrode. These breakdown levels are clearly lower than those measured with a fixed particle subjected to a positive step voltage. All these measurements were sensitive to the influence of carbon contaminants, especially under step impulse voltage. As concerns free particles, the breakdown is thought to be controlled in our experimental conditions by the initiation of positive streamers. Calculations showed that the initiation field at the particle tip is not constant but mainly depends on the particle diameter