Swamp rabbits (Sylvilagus aquaticus) are a bottomland hardwood forest specialist undergoing contraction at the northern extent of their range. This decline is often attributed to the loss of bottomland hardwood forest and frequent, intense flooding. To mitigate this decline and inform decisions regarding the swamp rabbit’s conservation status, there is a pressing need for long-term monitoring efforts. Although currently listed as imperiled (S2) in Missouri, shifts in occupancy trends may warrant a reassessment of the swamp rabbit’s state rank. The Missouri Department of Conservation has conducted decadal surveys for swamp rabbits since 1991, and the work presented here describes the fourth iteration of this study – 2022-2023. Repeated latrine surveys at 176 previously surveyed sites were conducted from November 2022 – April 2023 across 16 counties in southeast Missouri. Dynamic occupancy models were then used to estimate occupancy, colonization, extinction, and detection probabilities and identify environmental factors driving distribution changes since 2012. Additionally, I examined the impact of including ground latrines in swamp rabbit detection histories for the 2022-2023 survey season in a comparative single-season occupancy analysis. This analysis aimed to evaluate how the incorporation of ground latrines, as opposed to restricting detections to latrines on elevated surfaces, influenced estimates of occupancy and detection probabilities. Swamp rabbits were detected at 148 sites in 15 counties in 2022-2023, with a noted increase in occupancy probability from 0.66 (SE = 0.01) in 2010-2012 to 0.79 (SE = 0.01) in 2022-2023. As expected, site isolation negatively impacted occupancy probability, but predictors for patch richness density, site area, flood frequency, and flood severity had varying levels of support. For example, occupancy probability was negatively influenced by patch richness density but positively influenced by site area, while colonization probabilities were high and positively influenced by both flood frequency and severity. Extinction probability was low but was negatively influenced by flood frequency. Models with occupancy, colonization, and extinction as a function of the proportion of bottomland hardwood forest at a site were not supported. Detection probability decreased from 0.90 (SE = 0.19) in 2010-2012 to 0.78 (SE = 0.13) in 2022-2023. The inclusion of ground latrines in analyses did increase detection (0.68 to 0.84) and estimates of occupancy probabilities (0.95 to 1.00) but the change in estimates of occurrence was not biologically meaningful. Despite concerns about decline at the northern edge of their range, swamp rabbit populations in southeast Missouri appear to be expanding, evidenced by the increased occupancy and promising colonization and extinction rates. While long-term monitoring efforts should continue, managers should consider changing the swamp rabbit’s state rank from imperiled (S2) to vulnerable (S3).

Tesis por compendio / [EN] Vehicular Ad-hoc Networks (VANET) are a special type of networks where the nodes involved in the communication are vehicles. VANETs are created when several vehicles connect among themselves without the use of any infrastructure. In certain situations the absence of infrastructure is an advantage, but it also creates several challenges that should be overcome. One of the main problems related with the absence of infrastructure is the lack of a coordinator that can ensure a certain level of quality in order to enable the correct transmission of video and audio. Video transmission can be extremely useful in this type of networks as it can be used for videoconferencing of by traffic authorities to monitor the scene of an accident. In this thesis we focused on real time video transmission, providing solutions for both unicast and multicast environments. Specifically, we built a real-world testbed scenario and made a comparison with simulation results to validate the behavior of the simulation models. Using that testbed we implemented and improved DACME, an admission control module able to provide Quality of Service (QoS) to unicast video transmissions. DACME proved to be a valid solution to obtain a certain level of QoS in multi-hop environments. Concerning multicast video transmission, we developed and simulated several flooding schemes, focusing specifically on VANET environments. In this scope, the main contribution of this thesis is the Automatic Copies Distance Based (ACDB) flooding scheme. Thanks to the use of the perceived vehicular density, ACDB is a zeroconf scheme able to achieve good video quality in both urban and highway environments, being specially effective in highway environments. / [ES] Las redes vehiculares ad-hoc (VANET) son un tipo especial de redes en las que los nodos que participan de la comunicación son vehículos. Las VANETs se crean cuando diversos vehículos se conectan entre ellos sin el uso de ninguna infraestructura. En determinadas situaciones, la ausencia de infraestructura es una ventaja, pero también crea una gran cantidad de desafíos que se deben superar. Uno de los principales problemas relacionados con la ausencia de infraestructura, es la ausencia de un coordinador que pueda asegurar un determinado nivel de calidad, para poder asegurar la correcta transmisión de audio y vídeo. La transmisión de vídeo puede ser de extrema utilidad en este tipo de redes ya que puede ser empleada para videoconferencias o por las autoridades de tráfico para monitorizar el estado de un accidente. En esta tesis nos centramos en la transmisión de vídeo en tiempo real, proveyendo soluciones tanto para entornos unicast como multicast. En particular construimos un banco de pruebas real y comparamos los resultados obtenidos con resultados obtenidos en un entorno simulado para comprobar la fiabilidad de estos modelos. Usando el mismo banco de pruebas, implementamos y mejoramos DACME, un módulo de control de admisión capaz de proveer de calidad de servicio a transmisiones de vídeo unicast. DACME probó ser una solución válida para obtener ciertos niveles de calidad de servicio en entornos multisalto. En lo referente a la transmisión de vídeo multicast, desarrollamos y simulamos diversos esquemas de difusión diseñados específicamente para entornos VANET. En este campo, la principal contribución de esta tesis es el esquema de difusión "Automatic Copies Distance Based" (ACDB). Gracias al uso de la densidad vehicular percibida, ACDB es un esquema, que sin necesidad de configuración, permite alcanzar una buena calidad de vídeo tanto en entornos urbanos como en autopistas, siendo especialmente efectivo en este último entorno. / [CA] Les xarxes vehiculars ad-hoc (VANET) son un tipus de xarxes especials a les que els diferents nodes que formen part d'una comunicació son vehicles. Les VANETs es formen quan diversos vehicles es connecten sense fer ús de cap infraestructura. A certes situacions l'absència d'una infraestructura suposa un avantatge, encara que també genera una gran quantitat de desafiaments que s'han de superar. U dels principals problemes relacionats amb l'absència d'infraestructura, és la manca d'un coordinador que puga garantir una correcta transmissió tant de video com d'àudio. La transmissió de video pot ser d'extrema utilitat a aquest tipus de xarxes, ja que es por emprar tant per a videoconferències com per part de les autoritats de trànsit per monitoritzar l'estat d'un accident. A aquesta tesi ens centrem en transmissió de video en temps real, proporcionant solucions tant a entorns unicast como a entorns multicast. Particularment, vam construir un banc de proves i obtinguérem resultats que comparàrem amb resultats obtinguts mitjançant simulació. D'aquesta manera validarem la fiabilitat dels resultats simulats. Fent ús del mateix banc de proves, vàrem implementar i millorar DACME, un mòdul de control d'admissió, capaç de proveir de qualitat de servici a transmissions de video unicast. DACME va provar ser una bona solució per obtindré un bon nivell de qualitat de servici en entorns de xarxes ad-hoc amb diversos salts. Si ens centrem a la transmissió de video multicast, vàrem implementar i simular diferents esquemes de difusió, específicament dissenyats per al seu ús a entorns VANET. La principal contribució d'aquesta tesi es l'esquema de difusió ACDB (Automatic Copies Distance Based). Fent ús de la densitat vehicular, ACDB es capaç d'obtindre una bona qualitat de video tant a ciutats com a vies interurbanes, sent a especialment efectiu a aquestes últimes. A més a més no es necessària cap configuració per part de l'usuari. / Torres Cortés, Á. (2016). Efficient real-time video delivery in vehicular networks [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/62685 / Compendio

Flooding is of particular concern in low-lying coastal zones that are prone to impacts from multiple flooding drivers, such as coastal (storm surge and waves), fluvial (excessive river discharge), and pluvial (excessive surface runoff). Failure to account for dependence (and its changes over time) between flood drivers, when dependence exists between them, may lead to underestimation of flood risk and under-design of flood defense measures. Characterizing the dependence between compound flooding drivers in space and across seasons (tropical and extra-tropical), and how this dependence changed over time is essential in this context. In this dissertation, compound flooding potential from all relevant flooding drivers is assessed at 35 locations along the contiguous United States (CONUS) coastline. Different dependence measures are derived and analyzed using observations and state-of-the-art re-analysis data sets. In addition, temporal changes in the extremal dependence are assessed, using a sliding time window approach and possible associations with large-scale climate indices are explored. The effects of changes in dependence and marginal distributions over time between coastal and fluvial flooding drivers are investigated in more detail for a selected case study location. To overcome the computational expense of numerical modeling for flood mapping of large sets of events, a framework is introduced based on hybrid statistical modeling and one-dimensional hydraulic modeling combined with a flood inundation tool capable of propagating spatially variable along-river water surface elevations inland. The framework to delineate the flood transition zone is implemented for the Potomac River and different flood scenarios are analyzed to assess how different combinations of coastal water levels and river discharge modulate the flood hazard (specifically flood depth and extent). Overall, the findings provide new insights into characterizing compound flooding potential, its changes in space and time and how incorporating flood driver dependencies affects flood hazard.

Floodplain lakes are strongly regulated by river connectivity because floodwaters exert strong influence on the water balance, the physical, chemical and biological limnological conditions, and the influx of contaminants. The Peace-Athabasca Delta (PAD) in northern Alberta (Canada) is a hydrologically complex landscape and is an important node in the upper Mackenzie River Drainage Basin. The ecological integrity of the PAD is potentially threatened by multiple environmental stressors, yet our understanding of the hydroecology of this large floodplain remains underdeveloped. Indeed, ever since the planning and construction of the WAC Bennett Dam (1960s), concerns have grown over the effects of upstream human activities on the lakes of the PAD. More recently, concerns over the health of the PAD have intensified and come to the fore of national and international dialogue due to water abstraction and mining and processing activities by the rapidly expanding oil sands industry centred in Fort McMurray Alberta. Currently, widespread perception is that upstream human activities have reduced water levels and frequency of flooding at the PAD, which have lowered nutrient availability and productivity of perched basin lakes, and have increased supply of pollutants from oil sands. However, these perceptions remain based on insufficient knowledge of pre-impact conditions and natural variability. Current and past relations between hydrology and limnology of PAD lakes are mostly undocumented, particularly during the important spring freshet period when the effects of river flood waters are strongest. Similarly, knowledge of the deposition of oil-sands- related contaminants in the PAD remains insufficient to determine whether anthropogenic activities have increased the deposition of important oil-sands-related contaminants such as polycyclic aromatic compounds (PACs) relative to natural processes. Such knowledge gaps must be filled to achieve effective monitoring, policy and governance concerning impacts of industrial development and the protection of human and environmental health within the PAD and Mackenzie drainage basin. This thesis examines the effects of river flooding (and the lack of) on water clarity, nutrients, chemistry, phytoplankton abundance, epiphyton community composition and the deposition of polycyclic aromatic compounds (PACs) in lakes of the Peace-Athabasca Delta. To determine the role of flooding on contemporary epiphytic diatom communities (an abundant and diverse guild of primary producers in PAD lakes), a field experiment was conducted examining the community composition and abundance of epiphytic diatoms in four PAD lakes. Two of these four lakes had received floodwaters that spring and two had not. Epiphytic diatom communities in each lake were sampled during the peak macrophyte biomass period (summer) from two macrophyte taxa (Potamogeton zosteriformis, P. perfoliatus var. richardsonii) and from polypropylene artificial substrates previously deployed that spring. A two-way analysis of similarity (ANOSIM) test identified that epiphytic diatom community composition differed between lakes that flooded and those that did not flood. From the use of similarity percentage (SIMPER) analysis, diatom taxa were identified that discriminate between flooded and non-flooded lakes. The relative abundance of ‘strong flood indicator taxa’ was used to construct an event-scale flood record spanning the past ~180 years using analyses of sedimentary diatom assemblages from a closed-drainage lake (PAD 5). Results were verified by close agreement with an independent paleo-flood record from a nearby flood-prone oxbow lake (PAD 54) and historical records. Comparison of epiphytic diatoms in flooded and non-flooded lakes in this study provides a promising approach to detect changes in flood frequency, and may have applications for reconstructing other pulse-type disturbances such as hurricanes and pollutant spills. Additionally, this study demonstrates that artificial substrates can provide an effective bio-monitoring tool for lakes of the PAD and elsewhere. To improve our understanding of the hydrolimnological responses of lake in the PAD to flooding, repeated measurements over three years (2003-05) were made on a series of lakes along a hydrological gradient. This allowed the role of river flooding to be characterized on limnological conditions of lakes and to identify the patterns and timescales of limnological change after flooding. River floodwaters elevate lake water concentrations of suspended sediment, total phosphorus (TP), SO4 and dissolved Si (DSi), and reduce concentrations of total Kjeldahl nitrogen (TKN), DOC and most ions. River flooding increases limnological homogeneity among lakes, because post-flood conditions are strongly affected by the river water properties. After floodwaters recede, limnological conditions become more heterogeneous among lakes in response to diversity of local basin influences (geology, slope, vegetation, depth, fetch, and biological communities and processes), and limnological changes occur at two distinct timescales. In the weeks to months after flooding, water clarity increases as suspended sediments and TP settle out of the water column. In the absence of flooding for many years to decades, evaporative concentration leads to an increase in most nutrients (TKN, inorganic N, and dissolved P), DOC and ions. Contrary to a prevailing paradigm, these results suggest that regular flooding is not required to maintain high nutrient concentrations. In light of anticipated declines in river discharge, limnological conditions in the southern Athabasca sector will become increasingly less dominated by the short-term effects of flooding, and resemble nutrient- and solute-rich lakes in the northern Peace sector that are infrequently flooded. To determine the roles of the Athabasca River and atmospheric transport as vectors for the deposition of PACs in the PAD, sediment cores spanning the last ~200 years were collected from three lakes within the delta. A closed-drainage basin elevated well above the floodplain (PAD 18) was selected to determine temporal patterns of change in PAC concentration due to atmospheric deposition and within-basin production of PACs. Known patterns of paleohydrological changes at the other two lakes (PAD 23 and 31) were used to assess the role of the Athabasca River in delivering PACs to the Athabasca Delta during the ~200 year. Well- dated sediment core samples were analysed for 52 alkylated and non-alkylated PACs (method EPA 3540/8270-GC/MS). Sediments deposited in the non-flood prone lake (PAD 18) contained lower concentrations of total PACs compared to sediments deposited during flood-prone periods in the other study lakes, and were dominated by PACs of a pyrogenic rather than bitumen origin. Multivariate analysis of similarity tests identified that the composition of PACs differs between sediments deposited during not flood-prone and flood-prone periods. Subsequent Similarities Percentage (SIMPER) analysis was used and identified seven PACs that are preferentially deposited during flood-prone periods. These seven PACs are bitumen-associated, river-transported and account for 51% of the total PACs found in oil-sands sediment. At PAD 31, which has been flood-prone both before and since onset of Athabasca oil sands development, identified no measureable differences in both the proportion and concentration of the river-transported indicator PACs in sediments deposited pre-1940s versus post-1982. Our findings suggest that natural erosion of exposed bitumen along the banks of the Athabasca River and its tributaries is the main process delivering PACs to the Athabasca Delta, and that the spring freshet is a key period for contaminant mobilization and transport. Such key baseline environmental information is essential for informed management of natural resources and human-health concerns by provincial and federal regulatory agencies and industry, and for designing effective long-term monitoring and surveillance programs for the lower Athabasca River watershed in the face of future oil sands development. Further monitoring activities and additional paleolimnological studies of the depositional history of PACs and other oil-sands- and non-oil-sands-related contaminants is strongly recommended. Overall, results of this research identify that river flooding exerts strong control on physical, chemical and biological conditions of lakes within the PAD. However, contrary to prevailing paradigms, the PAD is not a landscape that has been adversely and permanently affected by regulation of the Peace River and industrial development of the oil sands along the Athabasca River. Instead, data from contemporary and paleolimnological studies identify that natural processes continue to dominate the delivery of water and contaminants to the delta. Regular and frequent flooding is not essential to maintain the supply of nutrients and productivity of delta lakes, which has been a widespread paradigm that developed in the absence of objective scientific data. Instead, nutrient concentrations rise over years to decades after flooding and lake productivity increases. During the thesis research, novel approaches were developed and demonstrated to be effective. Namely, new artificial substrate samplers were designed for aquatic biomonitoring that accrue periphyton and can identify the occurrence of flood events. Also, paleolimnological methods were employed to characterize the composition and concentration of PACs supplied by natural processes prior to oil sands industrial activity, which serves as an important benchmark for assessing industrial impacts. These are effective methods that can be employed to improve monitoring programs and scientific understanding of the factors affecting this world-renowned landscape, as well as floodplains elsewhere.

Översvämningar till följd av skyfall har blivit allt vanligare och förväntas att öka i takt med klimatförändringarna. Översvämningar kan ställa till stora skador för ett samhälle, framförallt när de samhällsviktiga verksamheterna blir drabbade. För att undvika att detta sker bör samhället vara byggt för att tåla stora volymer vatten som faller vid ett skyfall. Ett steg för att nå dit är att göra en skyfallskartering där flödesvägar, vattenvolymer och översvämningens utbredning tas fram genom hydraulisk modellering. Utifrån skyfallskarteringen kan sårbara områden upptäckas och förebyggande åtgärder kan utföras för att minska översvämningens negativa påverkan. Akademiska sjukhuset i Uppsala är en samhällsviktig verksamhet och har tidigare haft problem med översvämningar. I den här studien har en skyfallskartering utförts på Akademiska sjukhusets område för att ta reda på översvämningens utbredning vid ett skyfall och vilka åtgärder som lämpar sig för att förhindra översvämningar. Skyfallskarteringen utfördes i det tvådimensionella (2D) hydrauliska modelleringsprogrammet MIKE 21 Flow Model. Eftersom en skyfallskartering baseras på många generaliseringar finns det vissa osäkerheter kring valet av parametrar. Därför har även en känslighetsanalys utförts kring valet av regntyp (Chicago Design Storm (CDS) jämfört med ett blockregn), regnets varaktighet, grönytornas avrinningskoefficient och markens infiltrationshastighet. Indata till modellen baserades på olika kartdata som bearbetades i GIS-programmet ArcMap. Flera olika regn med varierande återkomsttid simulerades. Resultaten visade att det blir översvämning inne på sjukhusområdet vid ett 100-årsregn som förvärras när återkomsttiden ökar. Åtgärdsanalysen utfördes genom att lägga in förändringar i höjdmodellen för att se hur det påverkar översvämningens utbredning. Analysen visade att åtgärder som jordvallar och höjdsättning av marken kan tillämpas på området för att minska översvämningsrisken. Resultatet från känslighetsanalysen visade att ett CDS-regn ger större översvämningskonsekvenser i modelleringen än om ett blockregn av samma återkomsttid och varaktighet används. Känslighetsanalysen av varaktigheterna visade att en lång varaktighet kan leda till låga flödestoppar som inte representerar ett skyfall väl. En avrinningskoefficient på 0,4 beskriver infiltrationen i området väl och när en större avrinningskoefficient används tenderar översvämningen att bli större på grönytorna. Till sist visade resultatet att infiltrationshastigheten är en känslig parameter som bör väljas efter mer noggrann analys av marken i modelleringsområdet. / Flooding as a cause of cloudbursts have become more common and is expected to increase with climate change. Floods can cause substantial damage to a society, especially when the critical societal functions are affected. To avoid this the city should be built to tolerate large volumes of water from cloudbursts. As a step on the way to accomplish this, a cloudburst mapping could be made where flow paths, water volumes and the extent of the flooding are studied through hydraulic modelling. Through the cloudburst mapping, vulnerable areas can be spotted, and flood prevention measures can be taken to lessen the extent of the floods negative impact. Uppsala University Hospital serves a critical societal function and has previously had problems with flooding. In this project a cloudburst mapping has been made in the two dimensinoal (2D) hydraulic modelling program, MIKE 21. This was done to find out the extent of a flood caused by a cloudburst event and what measures that can be taken to prevent floods. A cloudburst mapping is based off many generalized assumptions and there are some uncertainties when selecting the parameters. Because of this, a sensitivity analysis was performed on the selection of rain-type (Chicago Design Storm (CDS) vs. block-rain), rain duration, the runoff coefficient and the soil's infiltration capacity. The inputs of the model were based off different geographic data and then constructed in the GIS-program ArcMap. Several different rain events with varying duration and return periods were simulated. The results showed that there is considerable flooding in the area after a rain with a 100-year return period and it gets worse when the return period increases. The flood prevention analysis was made by editing the terrain to mimic flood prevention measures and study how the extent of the flood responds to the edits. The analysis showed that measures like soil barriers and changes in elevation were effective in lessening the risk of flooding. The results from the sensitivity analysis showed that a CDS-rain causes a more significant flooding compared to a block-rain of the same return period and duration. The sensitivity analysis of the rain duration proved that a long duration can lead to flat flow curves that doesn't resemble a flow curve from a cloudburst event. A runoff coefficient of 0.4 describes the infiltration in the area well and with a larger coefficient the flooding on greenery tend to grow. Lastly, the infiltration capacity proved to be a sensitive parameter that needs to be selected carefully, preferably after a thorough soil analysis.

L'un des défis majeurs du monde de ces dernières décennies a été l'augmentation continue de la population des personnes âgées dans les pays développés. D’où la nécessité de fournir des soins de qualité à une population en croissance rapide, tout en réduisant les coûts des soins de santé. Dans ce contexte, de nombreux travaux de recherche portent sur l’utilisation des réseaux de capteurs sans fil dans les systèmes WBAN (Wireless Body Area Network), pour faciliter et améliorer la qualité du soin et de surveillance médicale à distance. Ces réseaux WBAN soulèvent de nouveaux défis technologiques en termes de sécurité et de protection contre les anomalies et les attaques. Le mode de communication sans fil utilisé entre ces capteurs et l’unité de traitement accentue ces vulnérabilités. En effet les vulnérabilités dans un système WBAN se décomposent en deux parties principales. La première partie se compose des attaques possibles sur le réseau des capteurs médicaux et sur le médium de communications sans fils entre ces capteurs et l’unité de traitement. La deuxième partie se compose des attaques possibles sur les communications à haut débit entre le système WBAN et le serveur médical. L’objectif de cette thèse est de répondre en partie aux problèmes de détection des attaques dans un système WBAN de surveillance médicale à distance. Pour atteindre cet objectif, nous avons proposé un algorithme pour détecter les attaques de brouillage radio (jamming attack) qui visent le médium de communications sans fils entre les capteurs et l’unité de traitement. Ainsi nous avons proposé une méthode de mesure de divergence pour détecter les attaques de type flooding qui visent les communications à haut débit entre le système WBAN et le serveur médical. / One of the major challenges of the world in recent decades is the continued increase in the elderly population in developed countries. Hence the need to provide quality care to a rapidly growing population while reducing the costs of health care is becoming a strategic challenge. In this context, many researches focus on the use of wireless sensor networks in WBAN (Wireless Body Area Network) systems to facilitate and improve the quality of medical care and remote monitoring. These WBAN systems pose new technological challenges in terms of security and protection against faults and attacks. The wireless communication mode used between the sensors and the collection node accentuates these vulnerabilities. Indeed vulnerabilities in a WBAN system are divided into two main parts. The first part consists of the possible attacks on the network of medical sensors and on the wireless communications medium between the sensors and the processing unit. The second part consists of possible attacks on high-speed communications between the WBAN system and the medical server. The objective of this thesis is to meet some of the problems of detecting attacks in a WBAN system for remote medical monitoring. To achieve this goal, we propose an algorithm to detect the jamming attacks targeting the wireless communications medium between the sensors and the processing unit. In addition we propose a method of measuring divergence to detect the flooding attacks targeting the high-speed communications between the WBAN system and the medical server.

Industrial control system or ICS is a critical part of the infrastructure in society. An example of ICS is the rail networks or energy plants like the nuclear plant. SCADA is an ICS system following a hierarchical structure. Due to the fact that a control system can be very large, monitoring remote through networks is an effective way to do so. But because of digitalization ICS or SCADA systems are vulnerable to cyber attacks that can hijack or intercept network traffic or deny legitimate user services. SCADA protocols (e.g. Modbus, DNP3) that are prone to get attacks due to not being a secure protocol make a SCADA system even more vulnerable to attacks. The paper focuses on how to best protect the network traffic between an HMI as the client and a different controller as the server from attacks. The proposed solution, the prototype, is based on the reverse proxy server setup to protect controllers from the external network traffic. Only the reverse proxy server, or gateway server, can forward a client request to the intended controller. The gateway server, a web-based solution, will be the additional security layer that encrypts the payload in the application layer using TLS version 1.2 by using HTTPS protocol, thereby protect from usual security threats. The prototype went through a penetration testing of MITM (Based on ARP-poisoning), SYN flooding, slow HTTP POST attacks. And the result indicated that the prototype was vulnerable to SYN flooding and the network traffic was intercepted by the MITM. But from the Confidentiality-Integrity-Availability (C.I.A) criteria, the prototype did uphold the integrity and confidentiality due to the TLS security and successful mitigation of certain attacks. The results and suggestions on how to improve the gateway server security were discussed, including that the testing was not comprehensive but that the result is still valuable. In conclusion, more testing in the future would most likely showcase different results, but that will only mean to better the security of the gateway server, the network that the client and gateway server runs in and the physical security of the location where the client and gateway server is located. / Industrial Control System (ICS, sve. Industriella Kontrollsystem) är en kritisk del av infrastrukturen i samhället. Ett exempel på ICS är järnvägsnät eller energianläggningar som kärnkraftverket. SCADA är ett ICS-system som följer en hierarkisk struktur. Eftersom ett kontrollsystem kan täcka stora ytor är fjärrövervakning och fjärrstyrning via nätverk ett effektivt sätt att göra det på. Men på grund av digitalisering är ICS- eller SCADA-system sårbara för cyberattacker som kan kapa nätverkstrafik eller förneka legitima användare från att nå vissa tjänster. SCADA-protokoll (t.ex. Modbus, DNP3) som är benägna att få attacker på grund av att de inte är ett säkert protokoll gör SCADA-system ännu mer sårbart för attacker. Uppsatsen fokuserar huvudsakligen på hur man bäst skyddar nätverkstrafiken mellan en HMI som klient och en annan controller som servern från attacker. Den föreslagna lösningen, prototypen, är baserad på hur en reverse proxy server är uppsatt för att skydda styrenheter från den externa nätverkstrafiken. Endast reverse proxy servern eller gateway-servern kan vidarebefordra en begäran från en klient till den avsedda styrenheten. Gateway-servern, en webbaserad lösning, kommer att vara det extra säkerhetslagret som krypterar nyttolasten (eng. payload) i applikationslagret med TLS version 1.2 med hjä lp av protokollet HTTPS, och därmed skyddar mot de mest förekommande säkerhetshot som vill se och påverka skyddad information. Prototypen genomgick en penetrationstestning av MITM (Baserat på ARP-poisoning), SYN-flooding, slow HTTP POST-attacker. Och resultatet indikerade att prototypen var sårbar för SYN-flooding och nätverkstrafiken avlyssnades genom MITM. Men baserad på kriterierna för C.I.A (sve. Konfidentialitet, Integritet och Tillgänglighet) upprätthöllprototypen integriteten och konfidentialiteten på grund av säkerhetsprotokollen TLSv1.2 och framgångsrika minskningar av vissa attacker. Resultaten och förslag på hur man kan förbättra prototypen diskuterades, inklusive att testningen inte var omfattande men att resultatet fortfarande är värdefullt. Sammanfattningsvis skulle fler tester i framtiden sannolikt visa ett helt annat resultat, men det kommer bara att innebära att förbättra säkerheten för gateway-servern, nätverket som klienten och gateway-servern kör i och den fysiska säkerheten för platsen där klienten och gateway-servern befinner sig inom.

Master of Science / Department of Geology / Saugata Datta / With the ever-rising atmospheric concentrations of CO₂ there arises a need to either reduce emissions or develop technology to store or utilize the gas. Geologic carbon storage is a potential solution to this global problem. This work is a part of the U.S. Department of Energy small-scale pilot studies investigating different areas for carbon storage within North America, with Kansas being one of them. This project is investigating the feasibility for CO₂ storage within the hyper-saline Arbuckle aquifer in Kansas. The study incorporates the investigation of three wells that have been drilled to basement; one well used as a western calibration study (Cutter), and the other two as injection and monitoring wells (Wellington 1-28 and 1-32). Future injection will occur at the Wellington field within the Arbuckle aquifer at a depth of 4,900-5,050 ft. This current research transects the need to understand the lateral connectivity of the aquifers, with Cutter being the focus of this study. Three zones are of interest: the Mississippian pay zone, a potential baffle zone, and the Arbuckle injection zone. Cored rock analyses and analyzed formation water chemistry determined that at Wellington there exists a zone that separated the vertical hydrologic flow units within the Arbuckle. This potential low porosity baffle zone within the Arbuckle could help impede the vertical migration of the buoyant CO₂ gas after injection. Geochemical analysis from formation water within Cutter indicates no vertical separation of the hydrologic units and instead shows a well-mixed zone. The lateral distance between Cutter and Wellington is approximately 217 miles. A well-mixed zone would allow the CO₂ plume to migrate vertically and potentially into potable water sources. Formation brine from Cutter was co-injected with supercritical CO₂ into a cored rock from within the Arbuckle (7,098 ft.). Results show that the injected CO₂ preferentially preferred a flow pathway between the chert nodules and dolomite. Post reaction formation chemistry of the brine showed the greatest reactivity occurring with redox sensitive species. Reactivity of these species could indicate that they will only be reactive on the CO₂ plumes front, and show little to no reactivity within the plume.

Flooding has the potential to have significant impact on the value of properties depending on the level of inherent vulnerability. Experts argue that it is not the actual risk but the perception of risk among property holders that influences vulnerability of value. The hypothesis that changing perception of flood risk could make property value vulnerable in the market is the main focus of the research. This dimension of research has received very low attention in commercial property literature. The existing knowledge base of flooding and property value reveals that focus has been largely associated with residential properties. Conceptual understanding of the extent and scale of the effect of flooding on the vulnerability of property value of commercial properties would be worthwhile for relevant stakeholders. The research methodology follows a quantitative approach with sequential application: of literature review, conceptual model generation, data collection from primary and secondary sources with remote questionnaire survey of selected study areas in the UK. The conceptual model was operationalised using analysis and interpretation of the collected data and finally cross validated with secondary data gained from commercial real estate experts . The strength of this research lies in the conceptualisation of the subject matter of property value in the context of flood vulnerability. This work provides innovative conceptual insight towards business vulnerability and vulnerability of value. The variables contributing towards vulnerability were hierarchically ranked using both collected data and deductive methods. The patterns of impact and recovery analysis emphasized that within the commercial sector indirect effects of flooding should be given equal importance with direct damages. The implication of perception on the vulnerability of property value showed a slightly different picture from business vulnerability in the chosen study areas when differentiated based on flood experience. In a nutshell the study reflected that the commercial property sector does not take flooding as one of their priorities. This is in part due to differential attitude towards risk of the population within the flood plain based on their knowledge and experience of flooding. The perception of stakeholders towards vulnerability of value can change with increasing magnitude and severity of floods and it is possible that the implications on market value of commercial properties will be visible in the future. Practitioners and researchers will find this study useful in developing an understanding of the vulnerability of commercial property value in the context of changing flood risk.

As easy target reservoirs are depleted around the world, the need for intelligent enhanced oil recovery (EOR) methods increases. The first part of this work is focused on modeling aspects of novel chemical EOR methods for naturally fractured reservoirs (NFR) involving wettability modification towards more water wet conditions. The wettability of preferentially oil wet carbonates can be modified to more water wet conditions using alkali and/or surfactant solutions. This helps the oil production by increasing the rate of spontaneous imbibition of water from fractures into the matrix. This novel method cannot be successfully implemented in the field unless all of the mechanisms involved in this process are fully understood. A wettability alteration model is developed and implemented in the chemical flooding simulator, UTCHEM. A combination of laboratory experimental results and modeling is then used to understand the mechanisms involved in this process and their relative importance. The second part of this work is focused on modeling surfactant/polymer floods using a fully implicit scheme. A fully implicit chemical flooding module with comprehensive oil/brine/surfactant phase behavior is developed and implemented in general purpose adaptive simulator, GPAS. GPAS is a fully implicit, parallel EOS compositional reservoir simulator developed at The University of Texas at Austin. The developed chemical flooding module is then validated against UTCHEM. / text