ROLE OF WEAK ZONE GEOMETRY AND RHEOLOGY IN THE GENERATION OF INTRAPLATE SEISMICITY

In intraplate seismic zones (e.g. the New Madrid Seismic Zone, NMSZ, in the southcentral United States), the source of stress that drives earthquake is very complex. Data from the NMSZ indicate 3 earthquake of magnitude M~7, occurring at an approximate interval of 500 years during the last 2000 years. One hypothesis that satisfies these conditions proposes that short-lived bursts of earthquakes may result from perturbations in the local or regional stress field. This causes relaxation of a lower crustal weak zone which drive repeated earthquakes. The number of earthquakes is dependent on the geometry and rheology of the weak zone. Using finite element techniques which employ contact surfaces to model discrete faulting events and a maximum shear stress criteria evaluated at each node. We investigate the relevant parameter space, as it affects the concentration of stress at the base of the seismogenic fault and the number of earthquakes generated over a given time interval. Parameters that can be varied include earthquake stress drop, background tectonic stress, and maximum shear stress at failure. Results show that solutions are non-unique. With the addition of existing observational evidence, however, we can place bounds on the range of parameters which satisfy above observations

Role of neurosonography in neonates with clinically suspected intracranial pathology

Background: Preterm neonates have a higher mortality and morbidity because of their greater risk for intracranial hemorrhage (ICH), hypoxic ischemic encephalopathy(HIE) which can lead to poor neurodevelopmental outcomes. The present study was conducted to evaluate neonates with clinically suspected intracranial pathology by neurosonography.Methods: Included neonates were those with clinically suspected intracranial pathology admitted to neonatal intensive care unit of the Bharati Vidyapeeth Medical College and Hospital (Deemed to be University), Sangli from October 2018 till December 2018. First cranial neurosonography was done between first and third day, second between 7th and 10th day of birth. HIE also known as Periventricular leukomalacia (PVL) grading was done using the De Varies et al, grading. Severity of ICH was graded according to Papile and Burstein classification(1978).Results: Of the total 60 neonates, 61.7% were preterm and rest at term. Mean APGAR score at 1 minute was 8.6 (range 5 to 10) and at 5 minutes was 9.58 (range 8 to 10). Mean ventricular index at the first assessment was 26.78% and 26.89% at the second assessment. Grade 1 HIE was found in 17 neonates on first assessment, and two had grade 2 HIE. Second assessment revealed grade 1 HIE in 20 neonates and grade 2 in two. First assessment revealed two neonates with grade 1 and grade 2 ICH, out of which one grade 2 ICH worsened to grade 3. Two neonates were found to have corpus callosal agenesis.Conclusions: Transcranial neurosonography stands as an excellent and reliable investigation of choice for neonates to detect HIE,ICH and intracranial congenital anomalies

New Approach for Protection of Distributed Generation using Islanding Technique

Power system's traditional view is characterized by the unidirectional flow of power from a centralized generation to consumers. But for modern view by introducing DGs (Distributed Generations) into distribution system, it results to bidirectional flow of power. Rapid progress in modern technology like wind turbine, fuel cell, photovoltaic and power electronics new innovation, also the demand of customers for better reliability and quality of power are forcing power industry to shift for DGs. Hence DG (distributed generation)has gained momentum in power industry because of de-regulation of market and environmental concerns. When DG continues its power supply even when portion of distributed system becomes isolated electrically from power system remainder, Islanding occurs. DG should have capacity to detect islanding detection for interconnecting DG to power distributed system. Recently industry practices to disconnect all DGs after islands occurrence. In order to achieve this goal, all DGs must equip with detection device for islanding. This is also called as anti-islanding device such as ROCOF relay and vector-surge relay. DOI: 10.17762/ijritcc2321-8169.150711