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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Expansion of liquid He-4 : through the Lambda transition

Dodd, Martin Edward January 1998 (has links)
No description available.
2

Supporting adaptation decisions through scenario planning: Enabling the effective use of multiple methods

Star, Jonathan, Rowland, Erika L., Black, Mary E., Enquist, Carolyn A.F., Garfin, Gregg, Hoffman, Catherine Hawkins, Hartmann, Holly, Jacobs, Katharine L., Moss, Richard H., Waple, Anne M. January 2016 (has links)
Scenario planning is a technique used to inform decision-making under uncertainty, and is increasingly applied in the field of climate change adaptation and policy. This paper describes applications that combine previously distinct scenario methods in new and innovative ways. It draws on numerous recent independent case studies to illustrate emerging practices, such as far stronger connections between researcher-driven and participatory approaches and cycling between exploratory and normative perspectives. The paper concludes with a call for greater support for, and collaboration among, practitioners with the argument that mixed methods are most effective for decision-making in the context of climate change challenges.
3

Scénáře a strategie Ekvádoru v kontextu nastupujícího narkoterorismu / Scenarios and Strategies for Ecuador in the Context of Emerging Narcoterrorism

Vargas Egas, Stephany Victoria January 2019 (has links)
CHARLES UNIVERSITY IN PRAGUE FACULTY OF SOCIAL SCIENCES Institute of Political Studies Master thesis 2019 Stephany Victoria Vargas Egas CHARLES UNIVERSITY IN PRAGUE FACULTY OF SOCIAL SCIENCES Institute of Political Studies Stephany Victoria Vargas Egas Scenarios and Strategies for Ecuador in the Context of Emerging Narcoterrorism Master thesis Prague 2019 Author: Stephany Victoria Vargas Egas Supervisor: Mgr. Bohumil Doboš Academic Year: 2018/2019 Bibliographic note VARGAS Stephany. Scenarios and Strategies for Ecuador in the Context of Emerging Narcoterrorism. 71p. Master thesis. Charles University, Faculty of Social Sciences, Institute of Political Studies. Supervisor Mgr. Bohumil Doboš Abstract In January 2018, Ecuador woke up to a series of attacks and kidnappings perpetrated by a group of dissidents of the Colombian Peace Accords that are said to be the operative arm of international drug cartels. Governmental reactions have been disappointing and unassertive, increasing the feeling of failure to keep the population safe. Based on "what are possible scenarios and strategies for Ecuadorian government in the context of increasing violence of narco-trafficking?" the present thesis will put in place a creative thinking scenario methodology to provide plausible answers to this central question with inputs...
4

A Scenario-directed Computational Framework To Aid Decision-making And Systems Development

Hobbs, Reginald L. (Reginald Lionel) 20 July 2005 (has links)
Scenarios are narratives that illustrate future possibilities or existing systems, and help policy makers and system designers choose among alternative courses of action. Scenario-based decision-making crosses many domains and multiple perspectives. Domain-specic techniques for encoding, simulating, and manipulating scenarios exist, however there is no general-purpose scenario representation capable of supporting the wide spectrum of formality from executable simulation programs to free-form text to streaming media descriptions. The claim of this research is that there is a computer readable scenario framework that can capture the semantics of a problem domain and make scenarios an active part of decision making. The challenge is to define a representation for scenarios that supports a wide range of discussion and comprehension activities while remaining independent of content and access mechanisms. This dissertation describes a scenario ontology derived by examining alternate forms of narrative: thought experiments, mental models, case-based reasoning, use cases, design patterns, screenwriting, film-editing, intelligent agents, and other narrative domains. The scenario conceptual model was based on an analysis of forms of narrative and the activities of storytelling. This method separates what a narrative is from how it is used. The research contribution is the development of the hyperscenario framework. A hyperscenario is a scenario representation containing link structures for navigation between scenario elements. The hyperscenario framework consists of the scenario ontology, scenario grammar, and a scenario specification called Scenario Markup Language (SCML). The results of the web-enabled simulation experiment validate the improvement on decision-making due to the hyperscenario framework.
5

Building Damage, Death and Downtime Risk Attenuation in Earthquakes

Huang, Yinghui 2012 May 1900 (has links)
Whether it is for pre-event prevention and preparedness or for post-event response and recovery of a catastrophic earthquake, estimates of damage, death and downtime (3d) losses are needed by engineers, owners, and policy makers. In this research, a quantitative "scenario-based" risk analysis approach as developed to investigate the 3d losses for buildings. The "Redbook Building" is taken as the typical New Zealand construction exemplar and analyzed for the 22 February 2011 Christchurch Earthquake. Losses are presented in the form of attenuation curves that also include the associated uncertainties. The spatial distribution of 3d damages over the height of buildings is also considered. It is thus shown that it is possible to discriminate between losses that lead to building replacement versus less severe losses that require structures to be repaired. The 3d loss results show that within the Christchurch city (17 km radial distance from the earthquake epicenter): (a) the expected physical damage loss ratio is about 50% of the property value; (b) the expected probability that someone is killed or seriously injured is about 4%; and (c) the expected downtime for the building being out of service is about 24 weeks. However, when considering various uncertainties, one can have 90% confidence that these loss estimations will be as high as: (a) complete loss (100% physical damage), implying structure has a great chance of collapse; (b) 8% possibility of fatality, implying deaths and significant injuries are likely; and (c) 1-year downtime due to post-event reconstruction demand surge. These informative results demonstrate that even though structures, such as the "Redbook Building", may have been well designed and constructed to contemporary standards, significant damage can still be expected and the downtime loss is particularly large. In order to solve this problem, new building structures should ideally be built stronger, include recentering attributes, and use Damage Avoidance Design (DAD) armoring connection details.
6

none

Wu, Chen-Yu 28 August 2008 (has links)
none
7

Writing on the wall scenario development in times of discontinuity /

Notten, Philip van. January 1900 (has links)
Proefschrift Universiteit Maastricht. / Met bibliogr., lit. opg., index.
8

Scenario Development for Water Resources Decision-making

Mahmoud, Mohammed January 2008 (has links)
With ever-increasing pressures on limited water supplies in arid regions, water managers are forced to make critical decisions about the management of water resources - sometimes under considerable uncertainty. Given the large number of stresses on existing water systems, proper management requires the consideration of all different factors that may contribute to water use and consumption. As water management becomes more focused on the issue of sustainability, processes traditionally thought of as non-water-related and irrelevant to water management are now becoming very pertinent. In particular, the consequences of changes in climate, population, land use, and various types of water usage (agricultural, environmental, domestic, and urban) are of considerable interest.With increasing uncertainty about the future, conventional methods of decision-analysis are increasingly unable to suitably quantify the future impacts of policy decisions, and they are also unable to provide a clear contrast between impacts of historical policy decisions and possible future management decisions. An analytical approach that is sensitive to qualitative effects of water-related decision-making will therefore be more useful towards improving management practices. Scenario development is one such tool that can be used to examine future implications of water management, and thereby shed light on the potential consequences of implementing different operational and institutional policies. The objective of this work is to propose a formal scenario development methodology applicable to water resources management issues. This framework is applied and evaluated on a regional scale for the U.S. southwest and on a local scale for the state of Arizona.The research presented here is comprised of several components; (i) a review of existing literature on scenarios, scenario studies, and scenario applications; (ii) a retrospective analysis of water management-related scenario applications that examines the implications of scenario-influenced strategies previously implemented in Arizona, (iii) the adoption of a formal scenario development approach for water resource issues within the arid and semi-arid regions of the U.S., utilizing an example application in the Upper San Pedro Basin in southern Arizona, and (iv) a comprehensive application of the scenario development process to the Verde River Watershed in northern Arizona through a simplified small-scale scenario case study approach.
9

Scenario Tree Generation and Multi-Asset Financial Optimization Problems

Geyer, Alois, Hanke, Michael, Weissensteiner, Alex 09 1900 (has links) (PDF)
We compare two popular scenario tree generation methods in the context of financial optimization: Moment matching and scenario reduction. Using a simple problem with a known analytic solution, we find that moment matching - accompanied by a check to ensure absence of arbitrage opportunities - replicates this solution precisely. On the other hand, even if the scenario trees generated by scenario reduction are arbitrage-free, the solutions to the approximate optimization problem represented by the reduced tree are biased and highly variable. These results hold for correlated and uncorrelated asset returns, as well as for normal and non-normal returns. (authors' abstract)
10

Objectively Defining Scenario Complexity: Towards Automated, Adaptive Scenario-Based Training

Dunn, Robert 01 January 2014 (has links)
Effective Scenario-Based Training (SBT) is sequenced in an efficient trajectory from novice to mastery and is well-grounded in pedagogically sound instructional strategies and learning theory. Adaptive, automated SBT attempts to sequence scenarios according to the performance of the student and implement the sequence without human agency. The source of these scenarios may take the form of a matrix constructed by Instructional Systems Designers (ISD), software engineers or trainers. The domain being instructed may contain procedures or concepts that are easily differentiated thus allowing quick and accurate determination of difficulty. In this instance, the sequencing of the SBT is relatively simple. However, in complex, domain-integrated instructional environments accurate and efficient sequencing may be extremely difficult as ISD, software engineers and trainers, without an objective means to calculate a scenario*s complexity must rely on subjectivity. In the Military, where time, fiscal and manpower constraints may lead to ineffective, inefficient and, perhaps, negative training SBT is a growing alternative to live training due to the significant cost avoidance demonstrated by such systems as the United States Marine Corps* (USMC) Abrams Main Battle Tank (M1A1) Advanced Gunnery Training System (AGTS). Even as the practice of simulation training grows, leadership such as the Government Accountability Office asserts that little has been done to demonstrate simulator impact on trainee proficiency. The M1A1 AGTS instructional sub system, the Improved Crew Training Program (ICTP), employs an automated matrix intended to increase Tank Commander (TC) and Gunner (GNR) team proficiency. This matrix is intended to guide the team along a trajectory of ever-increasing scenario difficulty. However, as designed, the sequencing of the matrix is based on subjective evaluation of difficulty, not on empirical or objective calculations of complexity. Without effective, automated SBT that adapts to the performance of the trainee, gaps in combat readiness and fiscal responsibility could grow large. In 2010, the author developed an algorithm intended to computationally define scenario complexity (Dunne, Schatz, Fiore, Martin & Nicholson, 2010) and conducted a proof of concept study to determine the algorithm*s effectiveness (Dunne, Schatz, Fiore, Nicholson & Fowlkes, 2010). Based on results of that study, and follow-on analysis, revisions were made to that Scenario Complexity (SC) algorithm. The purpose of this research was to examine the efficacy of the revised SC algorithm to enable Educators and Trainers, ISDs, and software engineers to objectively and computationally define SC. The research process included a period of instruction for Subject Matter Experts (SME) to receive instruction on how to identify the base variables that comprise SC. Using this knowledge SMEs then determined the values of the scenarios base variables. Once calculated, these values were ranked and compared to the ICTP matrix sequence. Results indicate that the SMEs were very consistent in their ratings of the items across scenario base variables. Due to the highly proceduralized process underlying advanced gunnery skills, this high degree of agreement was expected. However, the significant lack of correlation to the matrix sequencing is alarming and while a recent study has shown the AGTS to increase TC and GNR team proficiency (PM TRASYS, 2014a), this research*s findings suggests that redesign of the ICTP matrix is in order.

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