577 research outputs found

    Importance of Locating Strike in 2d Magnetotelluric Data Modeling

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    2D inversion is still believed as the fastest, cheapest, and most reliable method magnetotelluric data interpretation. Traditionally the magnetotelluric data are collected on 2D profile perpendicularly across an assumed geological strike. However there is no guarantee where the chosen strike is exactly or nearly same as true geoelectrical strike. For this purpose, 2D synthetic magnetotelluric impedance data of a simple 2D model were generated along a profile across the model. The data were inverted on various presumed strike in order to study how far the inverted model is deviated when the presumed strike is moved away to the true strike. By the aim, first the data were inverted as measured on 2D profile perpendicularly across true strike in order to see how the inversion works in the ideal case. Thedata were also inverted as measured on 2D profile perpendicularly across an assumed strike. The presumed strike deviated 60 degrees to the true strike was selected as an example of extreme case. The model inverted from the extreme presumed strike data is compared to the actual one. The inversions on determinant and combined TE and TM modes have been done as well for model resolution comparison

    The Different Magnetic Results of Anemi and PPM Measurements on the Buried Remains of a 13th Century Fortress

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    This study aimed to evaluate the different magnetic results of an electromagnetic induction with proton magnetometer measurements on an archaeological site. The electromagnetic induction allows measuring both the apparent magnetic susceptibility in part per thousand (ppt) and the apparent electrical conductivity in millisiemens (mS/m). A proton magnetometer measures the total magnetic intensity in nanotesla (nT), caused by the induced and remanent magnetisations. An archaeological site where historical documents indicated the presence of a 13th century fortress that built by Lamuri Sultanate was selected as a test area. The measurement were conducted by divided the study area into 10 profiles.Some standard data processing have been applied to the measured data. The result of the first survey with electromagnetic induction showed low magnetic anomalies in the buried remains of Lamuri fortress. The similar value are shown as well by low magnetic field intensity in magnetometer measurement

    Investigation of Shallow Paleochannel in Banda Aceh Based on Electrical Resistivity Tomography

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    Pembentukan daratan pesisir sangat dipengaruhi oleh proses sedimentasi dari material hasil rombakan. Proses sedimentasi pada masa lampau dapat dikaji dengan mempelajari sungai purba sebagai media transportasi material. Survey geofisika metode electrical resistivty tomography dilakukan untuk investigasi sungai purba di Ulee Kareng Banda Aceh. Untuk memetakan sedimen dan geometri sungai purba, pengukuran electrical resistivity dilakukan di sepanjang dua lintasan dengan panjang 240 meter dan spasi elektroda 2 meter. Proses inversi model resistivitas 2D telah dilakukan pada masing – masing lintasan data yang terukur. Hasil electrical resistivity tomography mampu membedakan batas – batas antara setiap lapisan sedimen yang terendapkan di lokasi paleochannel. Sedimen paleochannel secara jelas diidentifikasi dari distribusi nilai resistivitas yang lebih tinggi (15.2–31.6 Ω.m). Berdasarkan interpretasi dari metode electrical resistivity tomography area persawahan merupakan lokasi sungai purba pada masa lampau. The formation of coastal area is influenced by sedimentation process. The sedimentation process along the coastal line in the past one can be explained by studying existence of paleochannels located around the area. Deposition of the sediment along the coast is carried by river activities in the past. We have investigated paleochannel structure in Ulee Kareng, Banda Aceh using electrical resistivity tomography survey. The measurements were performed along two profiles with 240 meters and 2 meters spacing between electrodes crossing the paddy. The method measured apparent resistivity data along the profiles. The 2D resistivity models were inverted from the apparent resistivity data using Res2Div program. The inverted models clearly show indication of paleochannel structure based on distribution of resistivity values within the subsurface. The paleochannel area was characterize by high resistivity i.e. 15.2–31.6 Ω.m

    Kajian Awal Penentuan Daerah Prospek Panas Bumi di Gunung Bur Ni Telong Berdasarkan Analisis Data DEM SRTM dan Citra Landsat 8

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    Research for a preliminary study of Bur Ni Telong, geothermal area, Bener Meriah district using remote sensing techniques has been done. The aims of the research were to determine the morphological condition based on the fault and fracture (FFD) map from the interpreted digital elevation model (DEM) shuttle radar topography mission (SRTM) and to know the vegetation density and surface temperature distribution using Landsat 8 image. The DEM SRTM data were analyzed using the lineament pattern which related to faults and fractures. The vegetation density was calculated using normalized difference vegetation index (NDVI) transformation. The estimated surface temperature was used to locate temperature anomaly. Referring to the geographical map, the dense class area include Silih Nara-Ketol-Peulimbang to Peudada, Juli to Sawang, and Bandar area. The fault and fracture dominantly have directions in East-West and Northwest-Southeast. While based on NDVI map we conclude that the area is covered by dense vegetation, dominated by intermediate to dense of vegetation. The LST map shows the location of maximum surface temperature values are in agreement with residential areas and uncovered areas, as in the areas of Simpang Tiga Redelong and Takengon. Some geothermal manifestations are located in sparse to intermediate vegetation areas with high temperature

    Sandfly-Borne Viruses of Demonstrated/Relevant Medical Importance

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    Sandflies show distribution in a vast geographical area from Europe to Asia, Africa, Australia, and Central and South America where they can transmit a large number of viruses. Between these viruses, the most important are grouped into the Phlebovirus genus (family Phenuiviridae). Among them, several sandfly-borne phleboviruses cause self-limiting febrile disease (sandfly fever) or central and peripheral nervous system infections. Data concerning the geographic distribution of these phleboviruses has drastically increased during the last decade in both the new and the old worlds. The current situation depicts a high viral diversity with taxonomic groups containing human pathogenic and non-pathogenic viruses. This merits to provide insight to address the question of medical and veterinary public health impact of all these viruses, which are poorly studied. To do so, integrated and translational approaches must use ecological, epidemiological, serological and direct clinical evidence. Beside, other viruses transmitted by sandflies and belonging to Rhabdoviridae and Reoviridae families can also be of veterinary and public health importance. The chapter aims to provide a comprehensive view of the sandfly-borne viral pathogens of the public health impact on humans and other vertebrates in the old and new worlds

    Applying Agile Software Engineering On Medical Ubiquitous Computing (MUC)

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    Nowadays, people are involved in using computation capabilities to meet their daily life needs although most of the time they may be unaware as to how this actually happens. Ubiquities Computing is considered the future trend for providing unlimited computing capabilities that handle every service in human life. One of the most crucial implementation of Ubiquities Computing is in Medical and Hospital Service. This is due to their great importance in saving people's lives. The huge amount of data and information delivered by MUC systems draw the attention to the necessity of having a new and modern software engineering methodology; Agile Software engineering methodology is highly considered in the matter. In this paper, we present an implementation of applying agile SWE methodology on MUC System, research related issues are also discussed

    Seroprevalence of toscana Virus and sandfly fever sicilian virus in European bat colonies measured using a neutralization test

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    Toscana phlebovirus (TOSV) and Sicilian phlebovirus (SFSV) are endemic in the Mediterranean area where they are transmitted to humans by infected sandflies. Vertebrates of several species have been postulated to act as reservoirs of these viruses, but convincing evidence is still awaited. Among them, bats have been suggested, however documented evidence is lacking. Here we tested a total of 329 bats belonging to eight species collected from twelve localities in southern Spain for the presence of neutralizing antibodies specific to TOSV and SFSV. Positive sera were detected in Schreiber's long-fingered bat (Miniopterus schreibersii), mouse-eared Myotis (Myotis myotis), European free-tailed bat (Tadarida teniotis), and common serotine (Eptesicus serotinus) with the latter showing the highest prevalence rates for SFSV (22.6%) and TOSV (10%). There was no difference between females and males. Results suggest that bats are not likely to play a major role in the natural cycle of these two sandfly-borne phleboviruses. However, large breeding colonies of bats can be used as sentinels for surveillance of the presence of such viruses in a given locality. In addition, capture-recapture studies should be initiated in order to understand better the dynamics of TOSV and SFSV in bat populations
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