Šiaurės Lietuvos karstinis regionas – vienas iš labiausiai komplikuotų ir probleminių regionų. Dėl gamtinių ypatybių jame ypač sunkiai suderinami ekologiniai, ekonominiai ir socialiniai teritoriniai interesai. Tai lemia gilėjančius kraštotvarkinius konfliktus šioje teritorijoje. Problematiškiausia yra ta karstinio regiono dalis, kurioje tankiausias paviršinių karstinių darinių tinklas (Biržų, Pasvalio rajonai). Tai aktyvaus karsto zona, skirstoma pagal paviršinių karstinių darinių tankį bei jų atsiradimo intensyvumą. Tokį teritorijos suskirstymą lėmė ne proceso intensyvumas, bet problematiškas ūkinis panaudojimas. Šiaurės Lietuvos karstiniame regione per trumpą laiką atsiranda vis naujų reljefo formų, būna sunku ūkininkauti, tenka imtis specialių gamtosaugos priemonių, kurios skatina geriau pažinti karstinio reljefo raidos ypatumus. Šio darbo tikslas – išryškinti žemės naudojimo tendencijas Šiaurės Lietuvos karstiniame regione bei numatyti žemės ūkio plėtros, žemės naudojimo perspektyvas, atsižvelgiant į gamtinius ypatumus. Darbe analizuojami žemės ūkio paskirties žemės naudotojai, jų žemėnaudos dydis, siekiant numatyti žemės ūkio plėtros, žemės naudojimo perspektyvas. Išryškinti dirvožemio dangos savitumai, dirvų sukultūrinimas ir derlingumas (pagal ekonominius balus) skirtingo sukarstėjimo teritorijose. Analizei pasirinkta: Biržų rajono Širvėnos, Parovėjos, Pabiržės seniūnijos ir Pasvalio rajono Krinčino, Pasvalio apylinkių, Pušaloto seniūnijos. Ūkininkų ūkių veiklai... [toliau žr. visą tekstą] / The sinkhole region of Northern Lithuania is one of the most complicated and problematical regions. It is difficult to co-ordinate ecological, economical and social interests in the region because of the peculiarities of land and nature in it. This causes many conflicts connected to organization of land exploitation in this region. The most problematic district of the sinkhole region is the one where the sinkhole derivatives are very dense (regions of Birzai and Pasvalys). It is the zone of an active sinkhole, which is allocated according to sinkholes density along the surface and the intensity of appearance of them. Such an allocation was not determined by the intensively of the process itself. It was determined by a problematic employment of the land in an agricultural way. An active perfunctonary sinkhole zones is called to be the most complicated territories for employment of nature and ecology. One needs to have an exceptional knowledge about the territories mentioned in a case to employ them for agricultural purposes. New forms of relief are to appear in a very short period of time in the sinkhole region of Northern Lithuania. This makes farming difficult, special safety measures need to be taken into consideration. This stimulates to find out more about the peculiarities of the evolution of sinkhole relief. In this paper there are the users of agricultural land and their land-tenure analyzed in case to preview the expansion of agriculture and the perspectives of... [to full text]

Sinkholes are hazardous to buildings and their occupants, so a sensing device that can monitor underground changes is vital. Void Technology, developed in the Research and Development Center at Western Kentucky University, is creating a device that can improve monitoring for any movement underground. This device, created by Void Technology, is equipped with ESP8266, which is a Wi-Fi module that can send its information to the router in a wireless network. The focus of this thesis is on designing and developing an IOS framework application to show the signal strength capabilities in different buildings to find the optimum placement of the Void Technology devices. Each building, based on various construction materials, had different attenuations that could cause signal loss from the application to the ESP82266. The optimum place was found with this designed application. From this test experiment, it can be concluded that the application can show the signal strength based dBm. Thus, this new application is cost-effective as well as user friendly and which can help both the installer and homeowner to find the best position for installing The Void Technology with optimum signal strength.

In thesis thesis, studies associated with the rehabilitation of the Malatya-Narli No: 7 Railroad Tunnel are presented. The rehabilitation work includes cleaning of two collapses and stopping of deformations occurring in the tunnel as well as characterizing the rock-mass by evaluating the cores obtained from 67 drill holes. Due to two collapses ocurred in the tunnel a large sinkhole (15x10x20 meters) was developed at the surface and the tunnel closed to train traffic for 10 months (September, 2002-July, 2003) covering the initiation of Iraq War. Originally, the tunnel had been opened into the paleo-landslide material in 1930. The rock-mass surrounding the tunnel consists of limestones, metavolcanics, and schists. Although the main problem in the tunnel is the reduced tunnel span caused by displacements triggerred by underground water, poor rock mass and time dependent deformations, from engineering point of view the other problems can be sited as collapses occurred in the tunnel, sinkhole devoloped at the surface and unstable sections existing in the tunnel. During the field studies, 15 deformation monitoring stations were installed aimed at determining the deviation from tunnel alignment. In order to provide stability of the tunnel Self Drilling Anchors (Mai bolts) were installed systematically around the tunnel. The details of the rock reinforcement design was presented in this thesis.

Using low energy devices to communicate over the air presents many challenges to reach security as resources in the world of Internet Of Things (IoT) are limited. Any extra overhead of computing or radio transmissions that extra security might add affects cost of both increased computing time and energy consumption which are all scarce resources in IoT. This thesis details the current state of security mechanisms built into the commercially available protocol stacks Zigbee, Z-wave, and Bluetooth Low Energy, and collects implemented and proposed solutions to common ways of attacking systems built on these protocol stacks. Attacks evaluated are denial of service/sleep, man-in-the-middle, replay, eavesdropping, and in mesh networks, sinkhole, black hole, selective forwarding, sybil, wormhole, and hello flood. An intrusion detection system is proposed to detect sinkhole, selective forwarding, and sybil attacks in the routing protocol present in the communication stack Rime implemented in the operating system Contiki. The Sinkhole and Selective forwarding mitigation works close to perfection in larger lossless networks but suffers an increase in false positives in lossy environments. The Sybil Detection is based on Received Signal Strength and strengthens the blacklist used in the sinkhole and selective forwarding detection, as a node changing its ID to avoid the blacklist will be detected as in the same geographical position as the blacklisted node.

A new palaeopalynological investigation was conducted on 15 samples from four test-pits at the Gray Fossil Site (Bear Pit, Elephant Pit, Test Pit 2-2010, and Rhino Pit). In total, 50 morpho-species of miospores (including five species of spores, eight species of gymnosperm pollen, and 37 species of angiosperm pollen) and 18 morpho-species of freshwater algal micro-remains were identified. One new morphological species, related to zygospores of the Zygnemataceae, Stigmozygodites grayensis sp. nov., is proposed. The assemblage of fossil algae recovered provides insights into the palaeoenvironmental conditions of the uppermost (125 cm) part of the Gray Fossil Site sedimentary cover, deposited after the formation of a number of sinkholes, and the fill of the palaeosinkholes. Most of the algae identified prefer meso-to eutrophic conditions and are characteristic of stagnant to slowly flowing shallow fresh water. Therefore, the lacustrine fossiliferous sediments at the Gray Fossil Site represent pond deposits. The palaeopalynological analysis revealed differences in the composition of the miospore and algal assemblages of the pits studied, suggesting that the Test Pit 2-2010, Bear, and Elephant pits are similar and may have been formed in the same pond, while the presence of a higher percentage of algae in the Rhino Pit may indicate sedimentation in a separate water body.

A new palaeopalynological investigation was conducted on 15 samples from four test-pits at the Gray Fossil Site (Bear Pit, Elephant Pit, Test Pit 2-2010, and Rhino Pit). In total, 50 morpho-species of miospores (including five species of spores, eight species of gymnosperm pollen, and 37 species of angiosperm pollen) and 18 morpho-species of freshwater algal micro-remains were identified. One new morphological species, related to zygospores of the Zygnemataceae, Stigmozygodites grayensis sp. nov., is proposed. The assemblage of fossil algae recovered provides insights into the palaeoenvironmental conditions of the uppermost (125 cm) part of the Gray Fossil Site sedimentary cover, deposited after the formation of a number of sinkholes, and the fill of the palaeosinkholes. Most of the algae identified prefer meso-to eutrophic conditions and are characteristic of stagnant to slowly flowing shallow fresh water. Therefore, the lacustrine fossiliferous sediments at the Gray Fossil Site represent pond deposits. The palaeopalynological analysis revealed differences in the composition of the miospore and algal assemblages of the pits studied, suggesting that the Test Pit 2-2010, Bear, and Elephant pits are similar and may have been formed in the same pond, while the presence of a higher percentage of algae in the Rhino Pit may indicate sedimentation in a separate water body.

Tropical latitudes play an important role in global climate as they export moisture and energy pole-ward. Recent tests of predictive climate models against Holocene paleoclimate data show discrepancies between predicted and observed values in Tropical regions. Terrestrial paleoclimate records could help resolve these discrepancies by all allowing for better understand of the sensitive ocean-atmosphere climate dynamics in the tropics and by providing additional information from a diverse source of proxies. The Caribbean is an ideal location for study as its climate is influenced by both the Atlantic and Pacific Oceans. However, there are relatively few sources of paleoclimate proxies in this region due to its archipelagic nature. If Caribbean climate is to be thoroughly investigated, additional environments and climate proxies need to be investigated. As coastal systems are ubiquitous throughout the Caribbean, they are ideal for investigation of Holocene paleoclimate in this region. However, they can be ephemeral on millennial timescales making them challenging to use in paleoclimate analysis. This dissertation discusses new methods and basins that facilitate the study of these systems. Several important contributions have been made by this thesis. (1) Core scanning XRF data, when examined with additional proxies such as foraminifera, can be used to infer shifts in regional precipitation patterns in a coastal setting. Though these methods have been used before in deep basins, this represents the first use of core scanning XRF in a littoral setting. (2) The evolution of sinkhole sedimentation is reliant on both the morphology of the sinkhole and water level within the feature. This thesis shows that coastal systems are a viable source of paleoclimate information and which can hold valuable information for reconstructing climate. / Thesis / Master of Science (MSc)

Le sous-sol français est traversé par un nombre considérable de cavités souterraines naturelles ou anthropiques : après mine, carrières, karsts, tunnels et ouvrages civils abandonnés, etc. Ces cavités sont à l’origine de différents risques de mouvements de terrains tels que les effondrements localisés (fontis) et les affaissements qui peuvent être graves de conséquence pour les biens et les personnes. Pour réduire ce risque, un renforcement par géosynthétique des remblais sur cavités potentielles peut être mis en œuvre. C’est dans ce cadre que s’inscrit cette thèse menée au sein de l’INERIS (projet de recherche EREVAN - Evaluation et Réduction de la Vulnérabilité des biens exposés aux Aléas Naturels et miniers), en partenariat avec le laboratoire 3SR. L’un des objectifs de ces travaux est notamment de mieux appréhender, suite à l’ouverture d’une cavité sous-jacente, le comportement et les mécanismes d’effondrement des remblais renforcés par géosynthétique, en particulier cohésifs, afin d’en optimiser le dimensionnement.Dans le cadre de cette thèse, différentes expérimentations sur des modèles physiques de laboratoire et en vraie grandeur ont été réalisées. Les résultats obtenus en laboratoire ont permis de préciser le rôle mécanique des renforcements géosynthétiques dans le cas d’effondrement localisé sous un remblai granulaire ou/et cohésif, une importante base de données expérimentales a ainsi été constituée. Une expérimentation en vraie grandeur a permis de valider l’intérêt au plan technique, économique et environnemental de la technique de renforcement par géosynthétique des zones sujettes à des risques fontis.La contribution particulière de ce travail réside dans l’utilisation de modèles physiques et de techniques de mesures originales développés pour simuler l’apparition d’une cavité et suivre de manière quantitative les mécanismes induits notamment dans le cas des remblais cohésifs. En particulier, une évaluation précise des mécanismes de transferts de charge et de l’interaction sol – renforcement géosynthétique due à un effondrement localisé a été rendue possible par le développement et la validation d’une technique de traitements des résultats par photogrammétrie. L’intensité de la charge transmise par le sol sur le renforcement géosynthétique, la géométrie de sa répartition, ainsi que son évolution sous l’effet d’une surcharge éventuelle en surface ont ainsi été plus spécifiquement étudiées.Les résultats expérimentaux ont été comparés avec des formulations analytiques issues de méthodes de dimensionnement existant dans la littérature. Cette comparaison nous a permis de mieux cerner les domaines de validité des méthodes de dimensionnement analytiques actuelles du renforcement géosynthétique que ce soit pour le cas d’un remblai granulaire ou cohésif et dans certains cas de formuler certaines recommandations. / The French underground is occupied by a considerable number of natural or anthropogenic underground cavities: former mining areas, quarries, karsts, tunnels and abandoned civil structures, etc. These cavities are the source of various risks of ground movements such as sinkholes and subsidence which can have a large impact on the safety people and structures or infrastructures. In order to reduce this risk, a reinforcement of the embankments by geosynthetic in the zones of potential cavities can be implemented. In this context, the thesis has been funded and managed by INERIS (research project EREVAN - Evaluation and Reduction of the Vulnerability of the properties exposed to the natural and mining Hazards), in partnership with 3SR laboratory. One of the objectives of this research is in particular to better understand, further to the opening of an underlying cavity, the behavior and the mechanisms of collapse of reinforced embankment, especially in the case of cohesive soil, in order to optimize its design.As a part of this work, various experiments on physical models in laboratory and on site have been realized. The results obtained in laboratory allowed to determine the behavior of the geosynthetic reinforcement following the collapse of a granular or/and cohesive embankment over a cavity, an important experimental database has thus been established. Full scale experiment allowed to validate the technical, economic and environmental benefits of geosynthetic reinforcement of zones subject to sinkhole.The particular contribution of this work is in the use of original physical models and measurement techniques used to simulate the occurrence of a sinkhole and follow in an accurate quantitative way the involved mechanisms, notably in the case of a cohesive backfill. In particular, a specific evaluation of load transfer mechanisms and soil - geosynthetic reinforcement interaction due to sinkhole has been enabled by the development and the validation of an image processing technique. The intensity of the load transmitted by the ground onto the geosynthetic reinforcement, the geometry of its distribution, as well as its evolution due to possible overburden load have been specifically investigated.Experimental results have been compared with analytical formulations resulting from existing design methods in the literature. This comparison allowed us to better define the domains of validity of the current analytical methods for design of geosynthetic reinforcement whether for granular or cohesive backfill, and in certain cases to formulate some recommendations.

An understanding of what influences sinkhole formation and the ability to accurately predict sinkhole hazards is critical to environmental management efforts in the karst lands of southeastern Minnesota. Based on the distribution of distances to the nearest sinkhole, sinkhole density, bedrock geology and depth to bedrock in southeastern Minnesota and northwestern Iowa, a decision tree model has been developed to construct maps of sinkhole probability in Minnesota. The decision tree model was converted as cartographic models and implemented in ArcGIS to create a preliminary sinkhole probability map in Goodhue, Wabasha, Olmsted, Fillmore, and Mower Counties. This model quantifies bedrock geology, depth to bedrock, sinkhole density, and neighborhood effects in southeastern Minnesota but excludes potential controlling factors such as structural control, topographic settings, human activities and land-use. The sinkhole probability map needs to be verified and updated as more sinkholes are mapped and more information about sinkhole formation is obtained.

In der vorliegenden Arbeit wurde die Eintretenswahrscheinlichkeit von Tagesbrüchen und das Risikomanagement am Beispiel von Rohrleitungen in tagesbruchgefährdeten Gebieten des Mitteldeutschen Braunkohlenreviers umfassend beleuchtet. Im ersten Schritt wurden die Möglichkeiten und Grenzen der verschiedenen Überwachungs- und Sicherungsmaßnahmen analysiert. Es wird gezeigt, dass kein Überwachungsverfahren in der Lage ist, das unmittelbare Bevorstehen eines Tagesbruchs hinreichend genau zu prognostizieren. Die Verfahren können in der Regel nur Hinweise geben, die dann durch einen Spezialisten zu interpretieren sind. Die vorgestellten Sicherungsverfahren sind zwar teilweise in der Lage, den Tagesbruch oder seine Auswirkungen auf Rohrleitungen auf ein ungefährliches Maß zu senken. Jedoch sind diese Verfahren meist in der flächendeckenden Anwendung viel zu teuer. Um solche Verfahren nur noch punktuell an den größten Gefährdungsschwerpunkten einsetzen zu müssen, ist eine zuverlässige Bewertung der Eintrittswahrscheinlichkeit eines Tagesbruchs notwendig. Mit der Methodik der Spezifischen Bruchwahrscheinlichkeit kann erstmals die Eintrittswahrscheinlichkeit von Tagesbrüchen in einem Grubenfeld quantifiziert werden, worin auch die wesentliche wissenschaftliche Bedeutung der Arbeit liegt. Die Entwicklung von praktischen Zahlenwerten ermöglicht es, das Tagesbruchrisiko objektiv zu quantifizieren und somit die sicherheitstechnische Zulässigkeit der geplanten Oberflächennutzung zu bewerten.