Monitoring of simulated clandestine graves of dismembered victims using UAVs, electrical tomography, and GPR over one year to aid investigations of human rights violations in Colombia, South America

In most Latin American countries there are significant numbers of missing people and forced disappearances, over 90,000 in Colombia alone. Successful detection of shallow buried human remains by forensic search teams is difficult in varying terrain and climates. Previous research has created controlled simulated clandestine graves of murder victims to optimize search techniques and methodologies. This paper reports on a study on controlled test site results over four simulated dismembered victims' clandestine graves as this is sadly a common scenario encountered in Latin America. Multispectral images were collected once post-burial, electrical resistivity surveys were collected 4 times and ground penetrating radar (GPR) surveys collected three times up to the end of the 371 day survey monitoring period. After data processing, results showed that the multispectral dataset could detect the simulated clandestine and control graves, with electrical resistivity imaging relative high resistances over some of the simulated graves but not over the empty control graves. GPR results showed good imaging on the Day 8 surveys, medium imaging on the Day 294 surveys and medium to good imaging on the Day 371 surveys. Study implications suggest that, whilst clandestine graves of dismembered homicide victims would likely result in smaller-sized graves when compared to graves containing intact bodies, these graves can still potentially be detected using remote sensing and geophysical methods

Geophysical and botanical monitoring of simulated graves in a tropical rainforest, Colombia, South America

In most Latin American countries there are significant numbers of missing people and forced disappearances, currently ~74,000 only in Colombia. Successful detection of shallow buried human remains by forensic search teams is currently difficult in varying terrain and climates. Within this research we built four simulated clandestine burial styles in tropical rainforests, as this is a common scenario and depositional environment encountered in Latin America, to gain knowledge of optimum forensic geophysics detection techniques. The results of geophysically monitoring these burials using ground penetrating radar, magnetic susceptibility, bulk ground conductivity and electrical resistivity are presented from one to forty three weeks post-burial. Radar survey results with both the 250 MHz and 500 MHz frequency antennae showed good detection of modern simulated burials on 2D profiles and horizontal time slices but poor detection on the other simulated graves. Magnetic susceptibility, bulk ground conductivity and electrical resistivity results were generally poor at detecting the simulated targets. Observations of botanical variations on the test site show rapid re-growth of Malvaceae and Petiveria alliacea vegetation over all burials that are common in these forests, which can make detection more difficult

Redes inalámbricas de sensores para sistemas de monitoreo de estructuras civiles

Magíster en Ingeniería de Sistemas y ComputaciónMaestrí

Simulación y evaluación de redes ad hoc bajo diferentes modelos de movilidad

En la evaluación del desempeño de un protocolo para una red ad hoc, el protocolo debería ser probado en condiciones realistas, incluidos movimientos realistas de los usuarios móviles (un modelo de movilidad). En este artículo se revisan varios modelos de movilidad usados en simulaciones de redes móviles, incluidos modelos de movilidad que representan nodos móviles cuyo movimiento es independiente de los otros nodos móviles y modelos de movilidad que representan nodos móviles cuyos movimientos son dependientes de los otros (modelos de movilidad de grupos). Se presentan algunos resultados de la simulación en NS-2 que ilustran la importancia de escoger un modelo de movilidad en la simulación de un protocolo sobre redes móviles. Especificamente, se ilustra cómo los resultados de desempeño en una red ad hoc cambian drásticamente al cambiar, bien sea el modelo de movilidad, o bien los parámetros del modelo seleccionado o ambos

Simulación y evaluación de redes ad hoc bajo diferentes modelos de movilidad

En la evaluación del desempeño de un protocolo para una red ad hoc, el protocolo debería ser probado en condiciones realistas, incluidos movimientos realistas de los usuarios móviles (un modelo de movilidad). En este artículo se revisan varios modelos de movilidad usados en simulaciones de redes móviles, incluidos modelos de movilidad que representan nodos móviles cuyo movimiento es independiente de los otros nodos móviles y modelos de movilidad que representan nodos móviles cuyos movimientos son dependientes de los otros (modelos de movilidad de grupos). Se presentan algunos resultados de la simulación en NS-2 que ilustran la importancia de escoger un modelo de movilidad en la simulación de un protocolo sobre redes móviles. Especificamente, se ilustra cómo los resultados de desempeño en una red ad hoc cambian drásticamente al cambiar, bien sea el modelo de movilidad, o bien los parámetros del modelo seleccionado o ambos.In the performance evaluation of a protocol for an ad hoc network, the protocol should be tested under realistic conditions including realistic movements of the mobile users (a mobility model). In this paper we revise several mobility models used in the simulations of mobile networks including mobility models that represent mobile nodes whose movements are independent of each other and mobility models that represent mobile nodes whose movements are dependent on each other (group mobility models). We present simulation results in NS-2 that illustrate the importance of chossing a mobility model in the simulation of a mobile network protocol. Specifically, we illustrate how the performance results of an ad hoc network protocol drastically change as a result of changing the mobility model simulated

Simulation and evaluation of ad hoc networks under different mobility models

In the performance evaluation of a protocol for an ad hoc network, the protocol should be tested under realistic conditions including realistic movements of the mobile users (a mobility model). In this paper we revise several mobility models used in the simulations of mobile networks including mobility models that represent mobile nodes whose movements are independent of each other and mobility models that represent mobile nodes whose movements are dependent on each other (group mobility models). We present simulation results in NS-2 that illustrate the importance of chossing a mobility model in the simulation of a mobile network protocol. Specifically, we illustrate how the performance results of an ad hoc network protocol drastically change as a result of changing the mobility model simulated.En la evaluación del desempeño de un protocolo para una red ad hoc, el protocolo debería ser probado en condiciones realistas, incluidos movimientos realistas de los usuarios móviles (un modelo de movilidad). En este artículo se revisan varios modelos de movilidad usados en simulaciones de redes móviles, incluidos modelos de movilidad que representan nodos móviles cuyo movimiento es independiente de los otros nodos móviles y modelos de movilidad que representan nodos móviles cuyos movimientos son dependientes de los otros (modelos de movilidad de grupos). Se presentan algunos resultados de la simulación en NS-2 que ilustran la importancia de escoger un modelo de movilidad en la simulación de un protocolo sobre redes móviles. Especificamente, se ilustra cómo los resultados de desempeño en una red ad hoc cambian drásticamente al cambiar, bien sea el modelo de movilidad, o bien los parámetros del modelo seleccionado o ambos

Monitoring of simulated clandestine graves of victims using UAVs, GPR, electrical tomography and conductivity over 4-8 years post-burial to aid forensic search investigators in Colombia, South America

In Colombia there are estimated to be over 121,000 missing people and victims of forced disappearances. Forensic investigators therefore need assistance in determining optimal detection techniques for buried victims, to give victims’ families closure and for the wider community to see that justice is being served. Previous research has created 12 controlled simulated clandestine graves of typical Colombian murder victim scenarios at 0.5m – 1.2m depths in savannah and rainforest sites in Colombia. The 0-3 years of geophysical monitoring results of were published, with this paper reporting on 4-8 years monitoring of both UAV drone results and geophysical data. The UAV results from the year 8 survey, published for first time from Colombia, showed that the simulated graves could still be located using NDVI and NIR multi-spectral data, but not using optical or other multi-spectral data. The 0-3 years of geophysical data found the simulated clandestine graves could be detected with electrical resistivity and GPR methods, with the 4-8 year surveys evidencing that they could still be detected using bulk ground conductivity surveys, GPR horizontal time slice datasets and 2D ERT profiles. Research implications suggest initial use of UAV remote sensing technology to pinpoint likely search areas, before subsequent ground reconnaissance, geophysical surveys and their interpretation, before intrusive investigation methods are employed for detecting missing and disappeared persons in Colombia