Ant Colony Optimization Inversion Using the L1 Norm in Advanced Tunnel Detection

During the construction of the tunnel, there may be water-bearing anomalous structures such as fault fracture zone. In order to ensure the safety of the tunnel, it is necessary to carry out advanced tunnel detection. The traditional linear inversion method is highly dependent on the initial model in the tunnel resistivity inversion, which makes the inversion results falling into the local optimal optimum rather than the global one. Therefore, an inversion method for tunnel resistivity advanced detection based on ant colony algorithm is proposed in this paper. In order to improve the accuracy of tunnel advanced detection of deep anomalous bodies, an ant colony optimization (ACO) inversion is used by integrating depth weighting into the inversion function. At the same time, in view of the high efficiency and low cost of one-dimension inversion and the advantages of L1 norm in boundary characterization, a one-dimensional ant colony algorithm is adopted in this paper. In order to evaluate the performance of the algorithm, two sets of numerical simulations were carried out. Finally, the application of the actual tunnel water-bearing anomalous structure was carried out in a real example to evaluate the application effect, and it was verified by excavation exposure.

QUALITATIVE AND QUANTITATIVE INTERPRETATION OF HAND-DIGITIZED AEROMAGNETIC DATA FROM IDAH

Qualitative and Quantitative interpretation of hand-digitized aeromagnetic data from Idah has been carried out by applying forward and inverse modeling technique. Qualitatively, wavelength and amplitudes of source bodies reveal lithologic contrast, basement structure and sedimentary magnetization contrast. The maximum depth to top of the magnetic source body obtained is 16.8m and minimum depth is 0.5m. The anomalous bodies’ total magnetic intensity ranges from a minimum negative peak value of -153.5nT to maximum value of 162.7nT. Susceptibility values obtained reveals the presence of rocks such as granite, diabase, olivine-diabase, basalt/gabbro, quartzite and diorite. Results obtained shows that hand-digitized data competes favorably with computer digitized data

A More Efficient Observation Way With Electric Dipole Sources

The Ex and Hz amplitude are monotonic functions of the resistivity, and numerical algorithm can be utilized to obtain the high-precision apparent resistivity for all frequencies. On this basis, we focus on the comparative analysis of the resolution for Ex field, Hz field, and Cagniard apparent resistivity to conductive and resistance targets, which proves that the Ex field may have a better resolution for the resistance bodies, and the Hz field can better identify the conductive target. Besides, the electromagnetic data is often distorted by the static effect, which seriously affects the application effect of the electromagnetic method. The influence of the static effect on the Ex field, Hz field, is also analyzed. The apparent resistivity based on the Ex field and Cagniard apparent resistivity are severely affected by the static effect which can cover deep anomalous bodies, but the apparent resistivity based on the Hz field is almost unaffected by the static effect. At last, a more efficient observation way is provided for the resistance and conductive targets, respectively.

Ground-wire Source TEM 3D Full Time Multinary Inversion Using Adaptive Regulation

Ground-wire source transient electromagnetic method (GTEM) provides better investigation ability than loop source TEM at a given noise level and decay time. However, at the present time, the method still stays in the one-dimensional inversion interpretation stage. Since actual geological structures are three-dimensionally distributed, the three-dimensional electromagnetic forward and inversion are crucial for understanding the electromagnetic responses of complex geological structures. Moreover, the traditional 3D smooth inversions of geophysical data have been found to inaccurately reflect small-scale and isolated anomalies. In this study, a multinary inversion method was introduced and applied to GTEM inversions. It was found that the proposed method had the ability to enable GTEM to more accurately delineate anomalous bodies when applied to detect high-resistivity target. Then, for the purpose of avoiding the need for multiple inversion tests to determine the regularization factors, a self-adaptive scheme was proposed based on the differences between the data fitting functional and the model functional during each iteration step. It was observed that by introducing the multinary inversion with adaptive regulation, more stable and accurate inversion results were obtained. In the current study, the numerical simulation results had successfully verified that the proposed multinary inversion method had provided better resolution than the traditional inversion methods.

Niñez, transformación y consumo de maíz entre los nahuas de la Sierra Negra de Puebla / Childhood, transformation and corn consumption betweeen the nahuas de la Sierra Negra de Puebla

Para los nahuas de la Sierra Negra de Puebla, el consumo de maíz es considerado uno de los elementos que establecen la distinción entre los humanos y los no humanos, pues mediante este se crean cuerpos que se diferenciarán, entre otras cosas, por su estabilidad o la falta de ella. La fabricación del cuerpo requiere de una serie de acciones realizadas a lo largo de toda la vida. En este texto se dará cuenta, principalmente, de la importancia que tiene la alimentación mediante productos locales (por ejemplo, maíz y frijol) –frente a aquella que conforma cuerpos anómalos como el de los migrantes–, así como el consumo de sal y el bautizo, para dar paso a la descripción del papel que juega el trabajo en la milpa en la conformación de cuerpos adecuados para lo nahua, es decir, lo humano por excelencia. Se pondrá especial énfasis a la niñez como una etapa donde el control de la inestabilidad requiere de un esfuerzo mayor. Los niños nahuas son asociados a los antepasados, a lo acuoso y a lo mítico. Su humanidad está constantemente en riesgo, pues su cuerpo no ha llegado a los niveles necesarios de madurez.Abstract: For the Nahuas of the Sierra Negra de Puebla, the consumption of corn is considered one of the elements that establish the distinction between humans and non-humans, because through it bodies are created that will be differentiated, among other things, by their stability or the lack of it. The manufacture of the body requires a series of actions carried out throughout life. In this text, it will be realize, mainly, the importance of food through local products (corn and beans, for example) compared to that which forms anomalous bodies such as migrants, as well as the consumption of salt and baptism, for give way to the description of the role that work in the cornfield plays in shaping bodies suitable for “the Nahua”, that is, the human par excellence. Special emphasis will be given to children as a stage where the control of instability requires a greater effort. Nahua children are associated with the ancestors, the aqueous and the mythical. His humanity is constantly at risk, because his body has not reached the necessary levels of maturity.Keywords: childhood; transformation; food; Nahuas; Sierra Negra.Résumé : Pour les Nahuas de la Sierra Negra de Puebla, la consommation de maïs est considérée comme l’un des éléments permettant d’établir la distinction entre humains et non-humains, car grâce à elle, des corps sont créés qui se différencieront, entre autres, par leur stabilité ou le manque de ça. La fabrication du corps nécessite une série d’actions menées tout au long de la vie. Dans ce texte, il se rendra compte principalement l’importance de l’alimentation par le biais de produits locaux (par exemple, maïs et haricots) par rapport à celle qui forme des corps anormaux tels que les migrants, ainsi que la consommation de sel et le baptême, par exemple. Cédez le pas à la description du rôle que joue le travail dans le champ de maïs dans la formation d’organes propres au « Nahua », c’est-à-dire à l’humain par excellence. L’attention sera mise sur les enfants en tant qu’étape où la maîtrise de l’instabilité exige des efforts accrus. Les enfants nahuas sont associés aux ancêtres, aux aqueux et aux mythiques. Son humanité est constamment en danger, car son corps n’a pas atteint les niveaux de maturité nécessaires. Mots-clés : enfance ; transformation ; nutrition ; Nahuas ; Sierra Negra.

High resolution GPR investigations employing single and multichannel systems in the Necropolis of Monte Abatone, Cerveteri (Roma, Italy).

<p>The Monte Abatone Necorpolis is one of the main important necropolis of Cerveteri, located 60 km north of Rome (Latium, Italy). In this area, several tombs have been discovered and excavated from the 1800, though still many remain hidden underneath the subsurface.</p><p>In the last two years, geophysical surveys have been carried out to investigate the unexplored portions of the ancient Etruscan Necropolis, to provide a complete mapping of the position of the tombs. Ground Penetrating Radar and the Magnetometric methods have been used during 2018 to investigate few parts of the Necropolis. During 2019 (July and September) GPR system SIR 3000 (GSSI), equipped with a 400 MHz antenna with constant offset, SIR4000 (GSSI) equipped with a dual frequency antenna with 300/800 MHz and the 3D Radar Geoscope multichannel stepped frequency system were employed to survey 5 hectares where the presence of tombs was hypothesized from previous archaeological studies.</p><p>All the GPR profiles were processed with GPR-SLICE v7.0 Ground Penetrating Radar Imaging Software (Goodman 2017). The basic radargram signal processing steps included: post processing pulse regaining; DC drift removal; data resampling; band pass filtering; background filter and migration. With the aim of obtaining a planimetric vision of all possible anomalous bodies, the time-slice representation technique was applied using all processed profiles showing anomalous sources up to a depth of about 2.5 m.</p><p>The preliminary obtained results clearly show the presence of a network of strong circular features, linked with the buried structural elements of the searched tombs.</p><p>Together with archaeologists, these anomalies, have been interpreted to have a better understanding of the archaeological definition of these features and to enhance the knowledge of the necropolis layout and mapping; after the geophysical surveys, excavations have been conducted, which brought to light few of the investigated structures.</p><p> </p><p><strong>References</strong></p><p>Campana S., Piro S., 2009. Seeing the Unseen. Geophysics and Landscape Archaeology. Campana & Piro Editors. CRC Press, Taylor & Francis Group. Oxon UK, ISBN 978-0-415-44721-8.</p><p>Goodman, D., Piro, S., 2013. GPR Remote sensing in Archaeology, Springer: Berlin.</p><p>Piro S., Papale E., Zamuner D., Kuculdemirci M., 2018. Multimethodological approach to investigate urban and suburban archaeological sites. In “Innovation in Near Surface Geophysics. Instrumentation, application and data processing methods.”, Persico R., Piro S., Linford N., Ed.s. pp. 461 – 504, ISBN: 978-0-12-812429-1, pp.1-505, Elsevier.</p>

A Weighting Function-Based Method for Resistivity Inversion in Subsurface Investigations

There is a high demand for high detection accuracy and resolution with respect to anomalous bodies due to the increased development of underground spaces. This study focused on the weighted inversion of observed data from individual array type electrical resistivity tomography (ERT), and developed an improved method of applying a data weighing function to the geoelectrical inversion procedure. In this method, the weighting factor as an observed data weighting term was introduced into the objective function. For individual arrays, the sensitivity decreases with increasing electrode interval. Therefore, the Jacobian matrices were computed for the observed data of individual arrays to determine the value of the weighting factor, and the weighting factor was calculated automatically during inversion. In this work, 2D combined inversion of ERT data from four-electrode Alfa-type arrays is examined. The effectiveness of the weighted inversion method was demonstrated using various synthetic and real data examples. The results indicated that the inversion method based on observed data weighted function could improve the contribution of observed data with depth information to the objective function. It has been proven that the combined weighted inversion method could be a feasible tool for improving the accuracies of positioning and resolution while imaging deep anomalous bodies in the subsurface.

‘Blood in the Queer Eye’: Anomalous Bodies and Monsters in Lina Meruane’s Fictions

This essay focuses on the peculiar intersection which seems to explain unstable living forms – precarious ‘bodies in progress’ – that inhabit Lina Meruane’s ‘degenerated’ poetics, one where queer discourse mixes with fantastic and gothic features. Indeed, if, on the one hand, the Chilean author’s political agenda clings to the refusal of a disciplinating mould and objections to any request of identity accountability, on the other, she constantly counterbalances her revolutionary theoretical drive always flirting with narrative codes of the ominous, as illustrated by estranging, almost a ‘horror’ staging she intends for every one of her ambiguous, amorphous creatures.

An Array Source TEM Apparent Resistivity Conversion and Differential Conductivity Imaging Method and its Potential Applications

In this study, for the purpose of accurately detecting fissured disaster sources and diversion channels during tunnel construction, an array source transient electromagnetic device is proposed. Then, an apparent resistance conversion method and an approximate inversion algorithm for the proposed transient electromagnetic device are presented. First, a finite-difference time-domain (FDTD) method is used for the forward modeling of the proposed array source transient electromagnetic device, and the electromagnetic responses of the cracks and water-conducting channels are obtained. When compared with the transient electromagnetic square responses of the traditional loop sources, it is found that the data confirmed that the responses to the anomalies of the proposed array source transient electromagnetic device are more apparent. Then, the transformation from the array source transient electromagnetic field to the apparent resistivity is realized according to the principle of inverse function. In order to clearly identify the boundaries of the targeted anomalous bodies, a multi-source S-inversion algorithm is used to realize the array source transient electromagnetic differential imaging. The method is validated using a theoretical model. It was determined that the results of the differential imaging had effectively identified the boundaries of the anomalous bodies, and the apparent resistivity imaging had successfully determined the resistivity distributions of the anomalous bodies. Furthermore, a combination of the aforementioned methods is used to effectively identify the faults and water-flowing fractures in the model. This study's proposed algorithm was applied to the actually measured data, and the interpretation results were found to be consistent with the excavation results, which fully demonstrated the feasibility of the proposed method.