Application of electrical resistivity

Application of electrical resistivity Introduction Electrical resistivity imaging is a widely used tool in near surface geophysical surveys for investigation of various geological, environmental and engineering problems including landslide. In addition, a 2-D synthetic resistivity modelling study was carried out to understand the response of the resistivity method to a landslide problem before the field surveys (Drahor,MahmutG et al, 2006). The relevance of electrical surveys is to identify the subsurface resistivity distribution by making measurements on the ground surface. The true resistivity of the subsurface can be quantified from these measurements (Singh et al 2006). The ground resistivity is related to various geological parameters such as the mineral and fluid content, porosity and degree of water saturation in the rock. Electrical resistivity surveys have been used for many decades in hydrogeological, mining and geotechnical investigations. More recently, it has been used for environmental surveys. The resisti vity measurements are normally made by injecting current into the ground through two current electrodes (C1 and C2), and measuring the resulting voltage difference at two potential electrodes (P1 and P2). From the current (I) and voltage (V) values, an apparent resistivity (pa) value is calculated. pa = k V / I where k is the geometric factor which depends on the arrangement of the four electrodes. Resistivity meters normally give a resistance value, R = V/I, so in practice the apparent resistivity value is calculated by pa = k R The calculated resistivity value is not the true resistivity of the subsurface, but an â€Å"apparent† value which is the resistivity of a homogeneous ground which will give the same resistance value for the same electrode arrangement. The relationship between the â€Å"apparent† resistivity and the â€Å"true† resistivity is a complex relationship. An according to Singh et al (2006), an inversion of the measured apparent resistivity va lues using a computer program must be carried out to determine the true subsurface resistivity. Problem statement Landslide – Jalan Baru Gap ,Fraser Hill A recent problem faced in Malaysia is landslides on hill slopes. This harmful situation always occurred in highland area during wet season. One landslide occurred in km 90,FT055,Kuala Lumpur/Kuala Lipis (Gap Road/Tranum),Fraser Hill starting December 16 2007 until almost recently. This road is the only one that is connecting Kuala Kubu Baru or Fraser Hill to Raub. In recent tragedy on April 5 2008 at 9 pm,sliding of some boulders onto one old bridge in km 38.4,FT055,Kuala Kubu Road-Raub ,Fraser Hill ,Raub district, Pahang had occurred. The landslides are often triggered by water accumulation within part of the slope which leads to weakening of a section of the slope. Thus, it is important to accurately map the zone of ground water accumulation. Landslide is one of natural hazards that are often occur all over the world. In t ropical climate such as Malaysia, the phenomenon is common especially in hilly areas during monsoon season. According to the report by Jamaludin et al, 2006, serious natural landslides in this country normally occur in monsoon seasons where intense precipitation is the main triggering factor. Early indication of the slope stability prone area such as the landslide hazard maps may help planners and developers to choose favorable locations for locating development schemes. Careful engineering and geologic study could then follow before such specific project could be implemented.

Medusa Research Paper Example | Topics and Well Written Essays - 750 words

Medusa - Research Paper Example But for the date with Medusa he chose a place that was absolutely unacceptable – the temple of Athena. The virgin warrior got angry and not only turned the beauty into a winged monster, but also presented it with the terrifying force – to turn living creatures into stone. Poor Medusa, whose name is translated as "the patroness, the keeper" had to hide her ugly shape, and moved to the world’s end, to the forgotten island. Many years passed, but Athena couldnt calm down, until the hero Perseus came. The son of Zeus and Danai promised to bring Medusas head. Athena warned him not to look at Meduza, but only at her reflection, and presented his with the polished shield. Perseus also got help from Hermes, who gave him a sickle, with which it was possible to cut off Meduzas head. Then Perseus got winged sandals, a black cap of darkness and a magic bag for storage of the cut-off head of the victim. Having equipped, Perseus went to the country of hyperborean where among t he petrified sculptures of people and animals he saw the sleeping gorgon. Looking in a mirror shield at Medusas reflection, Perseus, directed by Athen, cut off the head of the unfortunate maiden with one stroke of a hand. He put the head into the bag. According to ancient myths, when Perseus was flying over the sea, red corals called gorgonaria grew on a place where the drops of gorgon’s blood fell in the water. According to myths, red corals were used as amulets protecting from "evil eye", from poisonings and even from gout. The earth in its turn made snakes out of drops of Medusa’s blood. The head of Medusa even after death kept the ability to turn living creatures into stone. Perseus landed near the palace of the titan Atlanta, which didnt show hospitality to the hero, He turned him into a mountain, having shown the gorgon’s head to him. Soon the cut-off head of Medusa was given to Athena, and she put in on her legendary shield – aegis, which received an epithet "gorgoneion",

Public Attitudes to Youth Crime Case Study Example | Topics and Well Written Essays - 1250 words

Public Attitudes to Youth Crime - Case Study Example The report involved applying a qualitative approach to research in which 125 participants were engaged; of which 68 were female while 57 were male. All the participants were between 18 and 76 years of age. A focus group methodology was then applied to analyzing the diversity and range of community attitudes towards youth perpetrated crime, and the reasons underlying the presented views. The article identified youth delinquency and antisocial behavior as a major source of concern and contributor to local crime statistics. Youth groups that often hang around neighborhoods and public spaces are described as intimidating presences that start out being moderately petty annoyances and disruptive in behavior, before moving on to behavior that could be intentionally intimidating and offensive, before graduating to committing outright violence. Antisocial behavior was also presented when the youth engaged in vandalism, damaged cars, smashed windows and place graffiti on public spaces. The art icle further argues that the local community had failed on curtailing youth delinquency and antisocial behavior, by failing to discipline the youth they condoned the behavior and allowed the youth to graduate into worse forms of delinquency. The local community and parents were not the only groups’ assigned blame for youth delinquency and antisocial behavior, the weak and ineffectual criminal justice system was also assigned blame. Poor parenting and the diminished sense of community were specifically identified as the major factors that allowed the youth to grow up without the understanding that their actions had consequences or respect for authority.