Vibration signal analysis for condition monitoring of puffer‐type high‐voltage circuit breakers using wavelet transform

Nowadays, the goals of electrical supply utilities are to reduce equipment failures, extend service life, increase equipment reliability, and reduce their related operating and maintenance costs. The high‐voltage circuit breaker is an important element in the electrical network. In order to determine or to detect abnormal conditions inside a circuit breaker, powerful vibration analytical techniques have been proposed. In this paper, a vibrational analysis is carried out by analyzing the signal in the time–frequency domain under no‐load switching operations with a commercially available high‐voltage puffer‐type circuit breaker without opening its major parts. Vibration of the circuit breaker poles, operating mechanism, and various monitored parameters were recorded under normal and variable operating conditions. Moreover, a synthetic mechanical damage introduced deliberately is also investigated. The experimental result indicates that mechanical defects can be detected by analyzing the vibration signal. © 2011 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

Predicting Shear Adhesion of Water-Based Pressure-Sensitive Adhesives via Transient Rheological Measurements

The relation between shear holding power and pressure-sensitive adhesive (PSA) rheological properties is investigated. Two constitutive models of PSA rheology, i.e., Newtonian and Power Law, are considered and experimentally tested for their ability to predict shear holding power. A Power Law model is found to be suitable for this purpose and is used to predict shear holding power with dynamic viscosity and steady shear viscosity measured by means of a transient creep experiment. Dynamic viscosity is shown to fail in predicting shear adhesion of high-viscosity PSA, whereas steady shear produces good agreement. It is demonstrated that the Cox-Merz rule does not hold for high-viscosity PSAs, explaining the need for steady shear viscosity data in modeling shear holding power.     

Star-shaped hexaaryltriindoles small molecules: Tuning molecular properties towards solution processed organic light emitting devices

We present a series of differently substituted star-shaped hexaaryltriindoles with tunable light-emitting properties. The deep blue emission is unchanged by donor peripheral substituents while an increasing acceptor character produces a reduction of the optical gap, an increased Stokes shift and eventually leads to the appearance of a new electronic level and to the simultaneous deep blue (413 nm) and green (552 nm) emission in solution. Quenching by concentration increases with the acceptor character but is lower as the tendency of these compounds to aggregate is stronger. Solution processed thin films present optical and morphological qualities adequate for device fabrication and similar electronic structure compared to solutions with an emission range from 423 nm up to 657 nm (red), demonstrating the possibility of tuning the energy levels by chemical functionalization. We have fabricated and characterized single-layer solution processed organic light emitting diodes (OLED) to investigate the influence on transport and emission properties of the substituting species. We analyzed the I–V response using a single-carrier numerical model that includes injection barriers and non-uniform electric-field across the layer. As a result, we obtained the electric field dependence of the mobility for each device. Best results are obtained on the most electron rich derivative functionalized with six donor methoxy groups. This material shows the highest emission efficiency in solid state, due to aggregation-induced enhancement, and better transport properties with the highest mobility and a very low turn-on voltage of 2.8 V. The solution processed OLED devices produce stable deep blue (CIE coordinates (0.16, 0.16)) to white (CIE coordinates (0.33, 0.3)) emission with similar luminous efficiencies.     

The human necdin gene, NDN, is maternally imprinted and located in the Prader-Willi syndrome chromosomal region

We introduce a case of an 18 years old man suspected of murder attempt of his colleague. We made a diagnosis of immature personality with schizoid features; we also want to remind Edward Brzezicki's thoughts on paragnomen.     

Rotibot: Use of Rotifers as Self‐Propelling Biohybrid Microcleaners

Self‐propelled biohybrid microrobots, employing marine rotifers as their engine, named “rotibot,” are presented and their practical utility and advantages for environmental remediation are demonstrated. Functionalized microbeads are attached electrostatically within the rotifer mouth and aggregated inside their inner lip. The high fluid flow toward the mouth, generated by the strokes of rotifer cilia bands, forces an extremely efficient transport of the contaminated sample over the active surfaces of the functionalized microbeads. The reactive particles confined around the rotifer's lip are thus exposed to a high flow rate of the pollutant solution, resulting in dramatically accelerated decontamination processes, without external mixing or harmful fuels. Theoretical simulations, modeling the greatly enhanced fluid dynamic associated with such built‐in mixing effect, correlate well with the experimental observations. The rotibot thus proves to be an effective, versatile, and robust dynamic microcleaning platform for removing diverse environmental pollutants. Microbeads functionalized with lysozyme and organophosphorus hydrolase enzymes are shown to be extremely useful for enzymatic biodegradation of Escherichia coli and the nerve agent methyl paraoxon, respectively, while ligand (meso‐2,3‐dimercaptosuccinic acid) modified beads are used for removing heavy metal contaminants. Rotifer‐based biohybrid microrobots hold considerable promise as self‐propelling dynamic pumps for diverse large‐scale environmental remediation applications.     

Development of atomic beam probe for tokamaks

The concept and development of a new detection method for light alkali ions stemming from diagnostic beams installed on medium size tokamak is described. The method allows us the simultaneous measurement of plasma density fluctuations and fast variations in poloidal magnetic field, therefore one can infer the fast changes in edge plasma current. The concept has been worked out and the whole design process has been done at Wigner RCP. The test detector with appropriate mechanics and electronics is already installed on COMPASS tokamak. General ion trajectory calculation code (ABPIons) has also been developed. Detailed calculations show the possibility of reconstruction of edge plasma current density profile changes with high temporal resolution, and the possibility of density profile reconstruction with better spatial resolution compared to standard Li-BES measurement, this is important for pedestal studies.