Increased renewable energy integration and international power trades have led to the construction development of new HVDC transmission systems. cables, in particular, play an important role undersea offshore having lower losses higher reliability. In this paper, current commercial feasibility cables different types accessories are reviewed. The non-uniform electric field distribution caused by applied voltage, temperature dependent conductivity, space charge accumulation is briefly...

Space charge formation in polymeric materials can cause some serious concern for design engineers as the electric field may severely be distorted, leading to part of material being overstressed. At worst, this result degradation and possibly premature failure. It is therefore important understand generation, trapping, detrapping processes material. In present paper, characteristics trapping low density polyethylene under dc have been investigated using pulsed electroacoustic technique. has...

Space charge formation in polymeric materials can cause some serious concern for design engineers as the electric field may severely be distorted, leading to part of material being overstressed. This result degradation and possibly premature failure at worst. It is therefore important understand generation, trapping, detrapping processes material. Trap depths density trapping states are they potentially related microstructure Changes these parameters reflect aging taken place In present...

The impact of nano-SiO₂ on the early hydration properties alite-sulphoaluminate (AC$A) cement was investigated with a fixed water to solid ratio (w/s) one. Nano-SiO₂ used in partial substitution AC$A at zero, one and three wt %. Calorimetry, X-ray diffraction (XRD), thermogravimetric/derivative thermogravimetric (TG/DTG), mercury intrusion porosimetry (MIP) scanning electron microscopy (SEM) analyses were characterize hydrates blended cement. significantly promoted, resulting an increase...

This paper describes a study on the surface potential decay of corona charged low density polyethylene (LDPE) films. A conventional charging process is used to deposit charge film and measured by compact JCI 140 static monitor. The results from multilayer sample reveal that bulk dominates decay. In addition, pulsed-electro-acoustic (PEA) technique has been employed monitor profiles in LDPE By using PEA technique, we are able migration through bulk. Charge consistent with results. Of further...

In this paper, the pulsed electroacoustic (PEA) technique that allows determination of space charge in a dielectric material has been used to monitor electrical potential decay corona-charged polyethylene films different thicknesses. To prevent possible disturbance surface during PEA measurements, two thin were placed on both sides sample. Charge profiles measured at times calculate across The obtained was compared with using conventional method. Good agreement obtained. More importantly,...

During the indoor visible light communication (VLC) channel modeling procedure, transmitter constituted by an array of light-emitting diodes (LED's) is frequently modeled as a single point source for convenience. However, how accurate this simplified treatment remains unanswered. This paper compares characteristics both point-source model and six practical cases having various numbers LEDs. Our numerical results show that deviations in terms channel's optical path loss (OPL), well its...

This paper focuses on the space charge behavior in oil-paper insulation systems used power transformers. It begins with importance of understanding systems, followed by introduction pulsed electrostatic technique (PEA). After that, research progress during recent twenty years is critically reviewed. Some important aspects such as environmental conditions and acoustic wave recovery need to be addressed acquire more accurate measurement results. breakthroughs materials team at University...

A feasible guidance scheme with impact time constraint is proposed for attacking a stationary target by missiles time-varying velocity. The main idea to replace the constant velocity future mean velocity; therefore, existing time-to-go estimation algorithm of proportional navigation law can be improved adapt varying conditions. In order obtain prediction profile, differential equation downrange derived, which numerically integrated between current and position on-board computer. Then,...

Space charge in polyethylene-based insulation materials and its effect on the local electric field under a dc environment have been extensively examined over last few decades while behavior of space ac stress has received less attention. phenomenon fields becomes an important issue with increased operating strength many applications, such as next generation high voltage cables. In this paper, bipolar transport model developed to simulate polymers fields. Obtained simulation results show that...

An ultra-wideband (UWB) transmitted reference (TR) system transmits an un-modulated pulse and a delayed modulated pair. Then, correlation receiver uses the former to demodulate latter. Because of long spread typical UWB channel, time delay between two pulses is preferable be larger than channel for reduced noise at receiver. However, bandwidth efficiency, that should made small, resulting in inter-pulse interference In this paper, digital receivers are constructed TR-UWB systems including...

High-voltage DC (HVDC) cables show more efficiency than high-voltage AC over the long distance power transmission and have attracted significant attention recently due to rapid developments in off-shore wind farm. Polypropylene laminated paper (PPLP) insulation based HVDC provided a reliable operation for many years are highest voltage level at moment. In this study, authors intend understand electrical performance of PPLP system by examining space charge detail, especially interfaces. It...