Verification of ANSI C37.90.1 SWC test generator outputs

Awareness of fast transient events in the electrical power environment has increased with the release of related test standards (ANSI C37.90.1 and IEC 801-4) and with increased usage of solid state circuits in utility equipment. Reliable measurement of the fast transient test waveforms and repeatable performance of test setups are persistent problems for equipment manufacturers and users. The construction, characterization, and usage of two high voltage test dividers for measurement of fast transient test waveforms are described. Measurements on a C37.90.1 (SWC) test generator are presented along with tutorial background. Proposals for changes to the ANSI C37.90.1 specification are included     

Comparison of smoothness evaluation devices for power cablecompounds

A variety of data from different devices has been generated on the smoothness of shield products, but no direct comparison of compound smoothness for the devices themselves has been made. The purpose of this study was to compare four different methods for evaluating the smoothness of power cable compounds. The methods compared include: image analysis, laser scanning, mechanical profilometry and photomicroscopy with visual rating. Extruded tape samples of conductor shields, filled insulations and strippable shields were evaluated     

A bidding decision index for construction contractors

Results from applying the model on a sample of contractors, the majority of whom were international and operating in Egypt, reinforces the credibility of the developed methodology, claim the authors.     

Detection of interphase instability from luminescence of reaction products

The reaction between chlorine and an alkaline solution of hydrogen peroxide is suggested for the investigation of chemothermocapillary convection [1].Vitebsk Branch of the Institute of Solid State and Semiconductors Physics, Academy of Sciences of Belarus, Vitebsk, Belarus. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 66, No. 1, pp. 30–33, January, 1994.     

ACT3: a high-speed, high-precision electrical impedance tomograph

Presents the design, implementation, and performance of Rensselaer's third-generation adaptive current tomograph, ACT3. This system uses 32 current sources and 32 phase-sensitive voltmeters to make a 32-electrode system that is capable of applying arbitrary spatial patterns of current. The instrumentation provides 16 b precision on both the current values and the real and reactive voltage readings and can collect the data for a single image in 133 ms. Additionally, the instrument is able to automatically calibrate its voltmeters and current sources and adjust the current source output impedance under computer control. The major system components are discussed in detail and performance results are given. Images obtained using stationary agar targets and a moving pendulum in a phantom as well as in vivo resistivity profiles showing human respiration are shown     

Endocytosis during postnatal differentiation in superficial cells of the mouse urinary bladder epithelium

This electron microscopical study was performed in order to follow the endocytic pathway of horseradish peroxidase and colloidal gold tracers and to determine the involvement of endocytosis in postnatal differentiation in superficial cells of the mouse urinary bladder epithelium. Morphometric analyses of late endosomes/multivesicular bodies from day of birth to day 25 were performed. The internalisation and intracellular transport of luminal plasmalemma to multivesicular bodies via endocytic vesicles, early endosomes and pleomorphic compartments was established. Dynamic changes in endocytic activity took place within the first few days of postnatal differentiation. During this period the number of multivesicular bodies changed in an inverse ratio to their size. After the third day endocytic activity gradually approached the low rate of adult urothelium.     

Radiation resistance of polymer materials

Affiliate of the L. Ya. Karpov Scientific-Research Institute of Physical Chemistry. Translated from Atomnaya énergiya, Vol. 76, No. 5, pp. 422–428, May, 1994.