Application of very-high-frequency (VHF) method to ceramic insulators

A VHF method (30-300 MHz) is applied to identify faults and defects in ceramic insulators. Insulators which exhibit internal cracks and fractures are used as test samples. Different artificial conditions are introduced to the test samples according to the IEC 507 standard under wet and dry conditions. Using a cascading signal processing technique and analysis methods such as FFT and fractal analysis, VHF signals acquired by digital scope are processed and analyzed. This study indicates that the fractal dimension can be used as an effective tool to isolate the common faulty conditions found on the ceramic insulators. The results from this study strongly support the prospect of using a VHF method to monitor the physical condition of ceramic insulators.

The Fiftieth Gate : an Australian case study in twentieth-century 'popular' publishing

On Sunday 6 April 1997, historian Mark Baker's first non-academic book was launched at Melbourne's iconic migrant portal, Station Pier. The guest list of over 500 invitees included representatives of many print media organisations, most of whom interviewed the author. His photograph was reproduced a week later in the 'Agenda' section of The Age newspaper. In this portrait, Baker leans on the railings beside the massive structure of Station Pier. Framed by sea and sky, he is caught glancing pensively over his shoulder past the camera and into the middle distance. He is alone. The day is bleak. Here, the reader is invited to surmise, is a man with much on his mind. In a flash of inspiration the sub-editor has prefaced the accompanying caption, 'Back to the future', linking the story with the mass media of film and television.

Study of acoustic emission (AE) caused by high voltage insulators

Acoustic emission (AE) study based on the acoustic signal ranges from 30MHz to 300MHz has been performed to diagnose the deterioration of insulation level in outdoor ceramic insulator. Different weather conditions combining with artificially created pollution were produced in laboratory and measurements were recorded over a fixed period of time. Pollution due to fine dust particles has been created according to IEC standard under wet and dry conditions. Samples that exhibit internal cracks and fracture were used in this study. The collected AE signals were sampled and analysed using fractal theory. The results of this study have clearly demonstrated the prospect of using AE technique to monitor the working condition of outdoor insulator.

Bi-cultural consultant is your key to the red gate

Chinese market is a uniquely challenging market to Western businesses. The difference is its uniqueness which majority of the organisations have been struggling with. Research has proven that cultural difference is the main barrier to success in China. Where companies are caught by surprise is the large gap between the two cultures. Standard training simply does not cut it.

Design of a high sensitive double-gate field-effect transistor biosensor for DNA detection

The study of interactions between organic biomolecules and semiconducting surfaces is an important consideration for the design and fabrication of field-effect-transistor (FET) biosensor. This paper demonstrates DNA detection by employing a double-gate field effect transistor (DGFET). In addition, an investigation of sensitivity and signal to noise ratio (SNR) is carried out for different values of analyte concentration, buffer ion concentration, pH, reaction constant, etc. Sensitivity, which is indicated by the change of drain current, increases non-linearly after a specific value (∼1nM) of analyte concentration and decreases non-linearly with buffer ion concentration. However, sensitivity is linearly related to the fluidic gate voltage. The drain current has a significant effect on the positive surface group (-NH2) compared to the negative counterpart (-OH). Furthermore, the sensor has the same response at a particular value of pH (5.76) irrespective of the density of surface group, although it decreases with pH value. The signal to noise ratio is improved with higher analyte concentrations and receptor densities.