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Development of an Integrity Evaluation System for Wells in Carbon Sequestration FieldsLi, Ben 03 February 2016 (has links)
<p> Carbon sequestration is a promising solution to mitigate the accumulation of greenhouse gases. Depleted oil and gas reservoirs are desirable vessels for carbon sequestration. It is crucial to maintain the sealing ability of carbon sequestration fields with high concentrations of CO<sub>2</sub>.</p><p> A systematic well integrity evaluation system has been developed and validated for carbon sequestration fields. The system constitutes 1) a newly developed analytical model for assessing cement sheath integrity under various operating conditions, 2) quantifications of well parameters contributing to the probability of well leakage, and 3) genetic-neural network algorithm for data analysis and well-leakage probability assessment.</p><p> A wellbore system consists of well casing, cement sheath, and formation rock. A new analytical stress model was developed. The new analytical model solves for the stresses in the casing-cement sheath formation system loaded by the isotropic and anisotropic horizontal in-situ stresses. Further analyses with the analytical model reveal that Young’s modulus of cement sheath is a major factor that contributes to the sealing ability of the cement sheath, while Poisson’s ratio and cohesion play less important roles in the cement sheath sealing ability. The cement sheath in the shale formation exhibits higher sealing ability than that in the sandstone formation. The sealing ability of weak cement is higher than that of strong cement.</p><p> Descriptive quantifications of well parameters were made in this study for analyzing their effect on the probability of well leakage. These parameters include well cement placement relative to aquifers and fluid reservoir zones, cement type, cement sheath integrity in operating conditions, well aging, and well plugging conditions. It is the combination of these parameters that controls the probability of well leakage. A significant proportion of wells were identified as risky wells in these two fields. It is concluded that the well trained neural network model can be used to predict the well leakage risk over the CO<sub>2</sub> sequestration lifespan, which can promote prevention activities and mitigations to the CO<sub>2</sub> leakage risky wells.</p>
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Self-organization and Sense-making in Architect-Engineer Design Teams| Leveraging Health Care's Approach to "Managing" Complex Adaptive SystemsSprauer, William A. 04 August 2016 (has links)
<p>Traditional, corporate-level risk mitigation procedures and management-led performance improvement efforts tend to ignore the relationship dynamics of Architect-Engineer design teams, and instead focus on the credentials and abilities of the individual designers, the contractual framework surrounding the individual projects, and the process for inspecting and controlling the quality of the team’s output, the design. Management may tacitly acknowledge the complex nature of the design process, but the notion of design teams as complex systems, or more precisely, Complex Adaptive Systems (CAS), with their inherently unpredictable behaviors, is not typically considered. </p><p> The research herein analyzed the team dynamics of 113 Architect-Engineer design projects to determine if teams that leveraged or embraced (deliberately or unknowingly) the <i>self-organizing</i> and <i>sense-making </i> properties of CAS, to include improvisation, an emphasis on intra- and cross-boundary communication, broad participation in decision-making, autonomy in managing resources, and deliberate use of conflict and uncertainty to alter standard behavior patterns, delivered more successful projects than teams whose leadership attempted (again, deliberately or unknowingly) to <i> overcome</i> those same CAS properties with detailed design or quality control (QC) procedures, a strong organizational identity that informed behavior, concentrated decision-making authority with a focus on efficiency of effort, and swift resolution of conflict. The parameters for measuring project success included adherence to schedule, project profitability, design errors, contractual disputes or litigation, and customer satisfaction. </p><p> An analysis of the data utilizing non-parametric analytical tools, to include Mann-Whitney Rank Sum analysis, calculation of Kendall’s tau-b, and ordinal logistic regression, reveals that while encouraging a design team to improvise can improve project outcomes, fostering or allowing self-organization in general is not associated with improved project performance. On the other hand, an environment that promotes team members’ sense-making abilities (although the use of conflict or noise as tools to promote adaptive thinking remains problematic) leads to improvements in project success factors. Finally, the results suggest that Architect-Engineer design team management is not a linear enterprise, and that in determining project success, the relationships between design team members may be as important as the technical competency of the designers and the design or quality control procedures they follow. </p>
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Balancing belligerents or feeding the beast| Transforming conflict trapsHayden, Nancy K. 30 June 2016 (has links)
<p> Since the end of the Cold War, recurring civil conflicts have been the dominant form of violent armed conflict in the world, accounting for 70% of conflicts active between 2000-2013. Duration and intensity of episodes within recurring conflicts in Africa exhibit four behaviors characteristic of archetypal dynamic system structures. The overarching questions asked in this study are whether these patterns are robustly correlated with fundamental concepts of resiliency in dynamic systems that scale from micro-to macro levels; are they consistent with theoretical risk factors and causal mechanisms; and what are the policy implications. </p><p> Econometric analysis and dynamic systems modeling of 36 conflicts in Africa between 1989 -2014 are combined with process tracing in a case study of Somalia to evaluate correlations between state characteristics, peace operations and foreign aid on the likelihood of observed conflict patterns, test hypothesized causal mechanisms across scales, and develop policy recommendations for increasing human security while decreasing resiliency of belligerents. Findings are that observed conflict patterns scale from micro to macro levels; are strongly correlated with state characteristics that proxy a mix of cooperative (e.g., gender equality) and coercive (e.g., security forces) conflict-balancing mechanisms; and are weakly correlated with UN and regional peace operations and humanitarian aid. Interactions between peace operations and aid interventions that effect conflict persistence at micro levels are not seen in macro level analysis, due to interdependent, micro-level feedback mechanisms, sequencing, and lagged effects. </p><p> This study finds that the dynamic system structures associated with observed conflict patterns contain tipping points between balancing mechanisms at the interface of micro-macro level interactions that are determined as much by factors related to how intervention policies are designed and implemented, as what they are. Policy implications are that reducing risk of conflict persistence requires that peace operations and aid interventions (1) simultaneously increase transparency, promote inclusivity (with emphasis on gender equality), and empower local civilian involvement in accountability measures at the local levels; (2) build bridges to horizontally and vertically integrate across levels; and (3) pave pathways towards conflict transformation mechanisms and justice that scale from the individual, to community, regional, and national levels.</p>
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Onlinespel : Vilka faktorer påverkar onlinespelandet och vad har spelandet för konsekvenser?Cheng, Taiwai, Wallberg, Eric January 2007 (has links)
<p>Spel via Internet har växt otroligt mycket de senaste åren. Tack vare det stora utbudet av olika sorters spel finns det spel som passar nästan alla.</p><p>Uppsatsen behandlar vilka faktorer som påverkar att olika sorters onlinespel blivit populära, hur användargränssnittet påverkar spelandet och vad spelandet har för konsekvenser.</p><p>Undersökningen genomfördes med hjälp av litteraturstudie, undersökning av spelklienter och enkätundersökning bland spelare.</p><p>Våra slutsatser är att det finns flera faktorer som påverkar spelandet, men det finns vissa faktorer som utmärker sig t.ex. vänner, utmaning och ett bra användargränssnitt är viktigt för spelaren.</p><p>Spelandet kan leda till både positiva och negativa konsekvenser som att spelaren utvecklas i t.ex. språk, men kan också bli spelberoende.</p>
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En studie om möjligheter att stoppa förfalskningar : Spårbarheten i en global världGrettve, Pierre January 2010 (has links)
<p>The purpose of this study is to describe the traceability of products that protect against counterfeiting and examine how protection against counterfeit products have been developed to date, and to display the opportunity to streamline the protection of products and brands.</p><p>Nowadays, in the global world, it is getting increasingly more difficult to track the products. Especially for the last link in the chain, which in most cases is the customer and who is constantly exposed to risks. This report deals with the possibilities of preventing and detecting counterfeit products. Fake products are not unusual in an historical perspective. It has been common with counterfeits ever since the Middle Ages continuously until today. Forgers have become more skillful and they are successful in most industries. Many of the fake products are of poor quality and can be downright dangerous to the customer.</p><p>To answer the question, the author used a qualitative collection method. Interviews took place with seven respondents from the pharmaceutical industry, government agencies and professional organizations. The study showed that all the interviewed pharmaceutical companies have been exposed to their products being copied. Despite attempts finding a common solution for the medical industry, nationally and internationally, such a solution has not yet been adopted. Each company has tried to protect themselves with several technical solutions. Authorities have been running campaigns, trying to get consumers to avoid buying counterfeit products.</p><p>Today the work is done through the development of laws, regulations, packaging, labelling and tracing techniques. It has been primarily done on a corporate or national level. This has until now often been ineffective because the counterfeiting industry is a global phenomenon.</p><p>The conclusion of this study is that in order to reach international harmonization, the legislation and regulation is required, to be able to interact with standardized techniques to detect and prevent fraud in the entire supply chain for each industry.</p> / <p>Syftet med studien är att beskriva produkters spårbarhet som skydd mot förfalskningar och undersöka hur skyddet mot produktförfalskningar har utvecklats fram till idag, samt att visa på möjligheter att effektivisera skyddet av produkter och varumärken.</p><p>Det är allt svårare att idag spåra produkter i vår globala värld. Inte minst för den som är sist i ledet, vilket är i de flesta fall konsumenten. Den person i kedjan som år efter år utsätter sig för risker. Denna rapport behandlar möjligheterna att förhindra och upptäcka förfalskningar av produkter. Förfalskade produkter är inget främmande för vår värld i ett historiskt perspektiv, det har förkommit förfalskningar och varumärkesstölder ända sedan medeltiden fram till idag. Förfalskarna har blivit skickligare och lyckats arbeta i de flesta branscher. Det är många förfalskningar som håller undermålig kvalité och är rent av livsfarliga för konsumenten.</p><p>För att besvara syftet har jag använt mig av en kvalitativ insamlingsmetod. Intervjuer har skett med sju respondenter från läkemedelsindustrin, myndigheter och branschorganisationer. Undersökningen har visat att samtliga läkemedelsföretag har varit utsatta för att deras produkter har kopierats. Trots ansatser till försök att få en gemensam lösning för bransch, nationellt eller internationellt så har en sådan lösning ännu ej tagits i bruk. Varje företag har försökt att skydda sig så gått man kunnat med olika tekniska lösningar. Myndigheter har genomfört kampanjer för att få konsumenter att undvika att köpa förfalskade produkter.</p><p>Arbetet som idag skett genom utveckling av lagstiftning, regler, förpackningar, märkningar och spårbarhetstekniker har skett i första hand på en företags eller nationell nivå. Detta har fram tills nu ofta varit verkningslöst eftersom förfalskningsindustrin idag är en global företeelse.</p><p>Slutsatsen blir att en internationell harmonisering krävs av lagstiftning och regler för att även kunna samverka med standardiserade tekniker för att kunna upptäcka och förhindra förfalskningar i hela distributionskedjan för varje bransch.</p><p> </p>
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Transboundary agreement| Case studies of marine mammal management in the bering straitAho, Kelsey B. 20 December 2016 (has links)
<p> The effectiveness of a state's natural resource management is rendered meaningless if the particular resource migrates into another state's jurisdiction. In the case of marine mammals, inadequate management of the species anywhere along their annual migration could make food insecure for the regional human populations. My research evaluates to what extent International Environmental Agreements have been able to manage transboundary challenges to food security. Two case studies, the <i>Polar Bear Agreement</i> (2000) and the <i>International Convention for the Regulation of Whaling</i> (1946), are analyzed quantitatively and qualitatively using Ronald Mitchell's four factors for describing variation of International Environmental Agreements' effectiveness: incentives, capacities, information, and norms. To ensure food security in the Bering Strait, this thesis stresses the importance of local concerns, norms and stakeholders. Transboundary management includes stakeholders at various scales to address a local challenge that is intersected by an international political boundary. The higher values of the Bowhead whale International Environmental Agreement's four factors, in the quantitative analysis, account for the higher level of food security for Bowhead whale. The qualitative analysis makes three recommendations for future International Environmental Agreements, in this case the draft U.S.-Russia agreement on Pacific walrus: 1) conservation of the Pacific walrus, 2) maintenance of Native self-determination and, 3) encouragement the flow of information between the local and federal stakeholders and between the United States and Russia. In order to ensure future food security in the Bering Strait Region, the management of the Pacific walrus depends on an effective International Environmental Agreement.</p>
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The Role of Canalization in the Spreading of Perturbations in Boolean NetworksManicka, Santosh Venkatiah Sudharshan 26 May 2017 (has links)
<p> Canalization is a property of Boolean automata that characterizes the extent to which subsets of inputs determine (canalize) the output. Here, we investigate the role of canalization as a characteristic of perturbation-spreading in random Boolean networks (BN) with homogeneous connectivity via numerical simulations. We consider two different measures of canalization introduced by Marques-Pita and Rocha, namely `effective connectivity' and `input symmetry', in a three-pronged approach. First, we show that the mean `effective connectivity', a measure of the true mean in-degree of a BN, is a better predictor of the dynamical regime (order or chaos) of the BN than the mean in-degree. Next, we combine effective connectivity and input symmetry in a single measure of `unified canalization' by using a common yardstick of Boolean hypercube ``dimension", a form of fractal dimension. We show that the unified measure is a better predictor of dynamical regime than effective connectivity alone for BNs with large in-degrees. When considered separately, the relative contributions of the two components of the unified measure changes systematically with the mean in-degree, where input symmetry becomes increasingly more dominant with larger in-degrees. As an application, we show that the said measures of canalization characterize the dynamical regimes of a suite of Systems biology models better than the in-degree. Finally, we introduce `integrated effective connectivity' as an extension of effective connectivity that characterizes the canalization present in BNs with arbitrary timescales obtained by iteratively composing a BN with itself. We show that the integrated measure is a better predictor of long-term dynamical regime than just effective connectivity for a small class of BNs known as the elementary cellular automata. This dissertation will advance theoretical understanding of BNs, allowing us to more accurately predict their short-term and long-term dynamic character, based on canalization. As BNs are generic models of complex systems, combining interaction graphs with multivariate dynamics, these results contribute to the complex networks and systems field. Moreover, as BNs are important models of choice in Systems biology, our methods contribute to the burgeoning toolkit of the field.</p>
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ALE Analytics| A Software Pipeline and Web Platform for the Analysis of Microbial Genomic Data from Adaptive Laboratory Evolution ExperimentsPhaneuf, Patrick 28 December 2016 (has links)
<p> Adaptive Laboratory Evolution (ALE) methodologies are used for studying microbial adaptive mutations that optimize host metabolism. The Systems Biology Research Group (SBRG) at the University of California, San Diego, has implemented high-throughput ALE experiment automation that enables the group to expand their experimental evolutions to scales previously infeasible with manual workflows. The data generated by the high-throughput automation now requires a post-processing, content management and analysis framework that can operate on the same scale. We developed a software system which solves the SBRG's specific ALE big data to knowledge challenges. The software system is comprised of a post-processing protocol for quality control, a software framework and database for data consolidation and a web platform named ALE Analytics for report generation and automated key mutation analysis. The automated key mutation analysis is evaluated against published ALE experiment key mutation results from the SBRG and maintains an average recall of 89.6% and an average precision of 71.2%. The consolidation of all ALE experiments into a unified resource has enabled the development of web applications that compare key mutations across multiple experiments. These features find the genomic regions <i> rph, hns/tdk, rpoB, rpoC</i> and <i>pykF</i> mutated in more than one ALE experiment published by the SBRG. We reason that leveraging this software system relieves the bottleneck in ALE experiment analysis and generates new data mining opportunities for research in understanding system-level mechanisms that govern adaptive evolution.</p>
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Optimized Reservoir Management for Downstream Environmental PurposesAdams, Lauren 16 March 2019 (has links)
<p> In regulated rivers, reservoir operation decisions largely determine downstream river temperature and flow. Computational methods can minimize the risk and uncertainty of making regrettable environmental release decisions and aid operations planning and performance prediction. Mathematical modeling in particular can optimize the timing and magnitude of reservoir release decisions for downstream benefit while accounting for seasonal uncertainty, water storage impact, and competing water demands. This dissertation uses optimization and modeling techniques, modifying traditional optimization modeling to include temporal correlation in outcome variables and incorporating long-term planning and risk management into prescribed reservoir operations. The proposed method is implemented in one case, a) with a state variable that tracks outcome benefits over time (fish population size) and, in another case, b) with a maximin stochastic dynamic program solution algorithm that maximizes net operational benefit and minimizes worst-case outcomes (for cold water habitat delivery). This method is particularly useful for environmental flow management, when the water quality and quantity of the river and reservoir in one time step affect the quantity and quality in the reservoir and the river for later periods. Better solutions with these methods internalize risk and hedge releases at the beginning of an operating season to maximize downstream benefit and reduce the probability of catastrophe for the season and future years. Maximizing the minimum cold-water habitat area over months of a season or multiple years, or maximizing a river indicator variable explicitly, could likely help, for example, maximize an out-migrating salmon smolt population downstream. The method is demonstrated with a case study optimizing environmental releases from Folsom Dam and another optimizing temperature management from Shasta Dam in northern California. These results inform general rules for environmental flow management and temperature management of reservoirs, with specific policy recommendations for both Folsom and Shasta reservoirs. In both cases, the added value from employing hedging rules help reservoir operations minimize the risk of environmental catastrophe and conserve storage both within an operating season and across years.</p><p>
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Understanding Social Movements through Simulations of Anger Contagion in Social MediaBacaksizlar, Nazmiye Gizem 06 March 2019 (has links)
<p> This dissertation investigates emotional contagion in social movements within social media platforms, such as Twitter. The main research question is: How does a protest behavior spread in social networks? The following sub-questions are: (a) What is the dynamic behind the anger contagion in online social networks? (b) What are the key variables for ensuring emotional spread? We gained access to Twitter data sets on protests in Charlotte, NC (2016) and Charlottesville, VA (2017). Although these two protests differ in their triggering points, they have similarities in their macro behaviors during the peak protest times. To understand the influence of anger spread among users, we extracted user mention networks from the data sets. Most of the mentioned users are influential ones, who have a significant number of followers. This shows that influential users occur as the highest in-degree nodes in the core of the networks, and a change in these nodes affects all connected public users/nodes. Then, we examined modularity measures quite high within users’ own communities. After implementing the networks, we ran experiments on the anger spread according to various theories with two main assumptions: (1) Anger is the triggering emotion for protests and (2) Twitter mentions affect distribution of influence in social networks. We found that user connections with directed links are essential for the spread of influence and anger; i.e., the angriest users are the most isolated ones with less number of followers, which signifies their low impact level in the network.</p><p>
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