Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

2017

Complexity

Discipline
Institution
Publication
Publication Type

Articles 1 - 11 of 11

Full-Text Articles in Physical Sciences and Mathematics

Sailing: Cognition, Action, Communication, Thora Tenbrink, Frank Dylla Dec 2017

Sailing: Cognition, Action, Communication, Thora Tenbrink, Frank Dylla

Journal of Spatial Information Science

How do humans perceive and think about space, and how can this be represented adequately? For everyday activities such as locating objects or places, route planning, and the like, many insights have been gained over the past few decades, feeding into theories of spatial cognition and frameworks for spatial information science. In this paper, we explore sailing as a more specialized domain that has not yet been considered in this way, but has a lot to offer precisely because of its peculiarities. Sailing involves ways of thinking about space that are not normally required (or even acquired) in everyday life. …


The Complexity Of Resilience, Cibele Matos Freire Nov 2017

The Complexity Of Resilience, Cibele Matos Freire

Doctoral Dissertations

One focus area in data management research is to understand how changes in the data can affect the output of a view or standing query. Example applications are explaining query results and propagating updates through views. In this thesis we study the complexity of the Resilience problem, which is the problem of finding the minimum number of tuples that need to be deleted from the database in order to change the result of a query. We will see that resilience is closely related to the well-studied problems of deletion propagation and causal responsibility, and that analyzing its complexity offers important …


Processing Conservation Indicators With Open Source Tools: Lessons Learned From The Digital Observatory For Protected Areas, Lucy Bastin, Andrea Mandrici, Luca Battistella, Grégoire Dubois Sep 2017

Processing Conservation Indicators With Open Source Tools: Lessons Learned From The Digital Observatory For Protected Areas, Lucy Bastin, Andrea Mandrici, Luca Battistella, Grégoire Dubois

Free and Open Source Software for Geospatial (FOSS4G) Conference Proceedings

The European Commission has a commitment to open data and the support of open source software and standards. We present lessons learnt while populating and supporting the web and map services that underly the Joint Research Centre's Digital Observatory for Protected Areas. Challenges include: large datasets with highly complex geometries; topological inconsistencies, compounded by reprojection for equal-area calculations; multiple different representations of the same geographical entities, for example coastlines; licensing requirement to continuously update indicators to respond to monthly changes in the authoritative data. In order to compute and publish an array of indicators, we used a range of open …


A Simple Linear Time Algorithm For Computing A 1-Median On Cactus Graphs, Kien T. Nguyen, Pham V. Chien, Ly H. Hai, Huynh D. Quoc Jun 2017

A Simple Linear Time Algorithm For Computing A 1-Median On Cactus Graphs, Kien T. Nguyen, Pham V. Chien, Ly H. Hai, Huynh D. Quoc

Applications and Applied Mathematics: An International Journal (AAM)

We address the problem of finding a 1-median on a cactus graph. The problem has already been solved in linear time by the algorithms of Burkard and Krarup (1998), and Lan and Wang (2000). These algorithms are complicated and need efforts. Hence, we develop in this paper a simpler algorithm. First, we construct a condition for a cycle that contains a 1-median or for a vertex that is indeed a 1-median of the cactus. Based on this condition, we localize the search for deriving a 1-median on the underlying cactus. Complexity analysis shows that the approach runs in linear time.


Reactivity Of Ketyl And Acetyl Radicals From Direct Solar Actinic Photolysis Of Aqueous Pyruvic Acid, Alexis J. Eugene, Marcelo I. Guzman Mar 2017

Reactivity Of Ketyl And Acetyl Radicals From Direct Solar Actinic Photolysis Of Aqueous Pyruvic Acid, Alexis J. Eugene, Marcelo I. Guzman

Chemistry Faculty Publications

The variable composition of secondary organic aerosols (SOA) contributes to the large uncertainty for predicting radiative forcing. A better understanding of the reaction mechanisms leading to aerosol formation such as for the photochemical reaction of aqueous pyruvic acid (PA) at λ ≥ 305 nm can contribute to constrain these uncertainties. Herein, the photochemistry of aqueous PA (5-300 mM) continuously sparged with air is re-examined in the laboratory under comparable irradiance at 38° N at noon on a summer day. Several analytical methods are employed to monitor the time series of the reaction, including (1) the derivatization of carbonyl (C═O) functional …


Hyporheic Flow Possibilities Within Lamprey (Petromyzon Marinus) Redds On The Blackledge River In Marlborough Connecticut, Samuel Fixler Jan 2017

Hyporheic Flow Possibilities Within Lamprey (Petromyzon Marinus) Redds On The Blackledge River In Marlborough Connecticut, Samuel Fixler

Environmental Studies Honors Papers

The fluvial geomorphic process of hyporheic flow provides critical nutrients and dissolved oxygen to macroinvertebrates and eggs within riverbeds through hyporheic exchange. Hyporheic flow may operate at similar scales within sea lamprey (Petromyzon marinus) redds. Limited documentation exists on the hyporheic processes within lamprey redds. This study attempts to measure hyporheic flow using a saline injection syringe and salinity probe to record salinity-time curves. The method was applied to several redds on the Blackledge River, Marlborough, Connecticut. The second aspect of this study examined the hydraulic properties of lamprey redds within a controlled environment in a 0.5 m …


Protected Areas As Social-Ecological Systems: Perspectives From Resilience And Social-Ecological Systems Theory, Graeme S. Cumming, Craig R. Allen Jan 2017

Protected Areas As Social-Ecological Systems: Perspectives From Resilience And Social-Ecological Systems Theory, Graeme S. Cumming, Craig R. Allen

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Conservation biology and applied ecology increasingly recognize that natural resource management is both an outcome and a driver of social, economic, and ecological dynamics. Protected areas offer a fundamental approach to conserving ecosystems, but they are also social-ecological systems whose ecological management and sustainability are heavily influenced by people. This editorial, and the papers in the invited feature that it introduces, discuss three emerging themes in social-ecological systems approaches to understanding protected areas: (1) the resilience and sustainability of protected areas, including analyses of their internal dynamics, their effectiveness, and the resilience of the landscapes within which they occur; (2) …


Complexity Of Linear Summary Statistics, Micah G. Pedrick Jan 2017

Complexity Of Linear Summary Statistics, Micah G. Pedrick

HMC Senior Theses

Families of linear functionals on a vector space that are mapped to each other by a group of symmetries of the space have a significant amount of structure. This results in computational redundancies which can be used to make computing the entire family of functionals at once more efficient than applying each in turn. This thesis explores asymptotic complexity results for a few such families: contingency tables and unranked choice data. These are used to explore the framework of Radon transform diagrams, which promise to allow general theorems about linear summary statistics to be stated and proved.


Emergence And Complexity In Music, Zoe Tucker Jan 2017

Emergence And Complexity In Music, Zoe Tucker

HMC Senior Theses

How can we apply mathematical notions of complexity and emergence to music, and how can these mathematical ideas then inspire new musical works? Using Steve Reich's Clapping Music as a starting point, we look for emergent patterns in music by considering cases where a piece's complexity is significantly different from the total complexity of each of the individual parts. Definitions of complexity inspired by information theory, data compression, and musical practice are considered. We also consider the number of distinct musical pieces that could be composed in the same manner as Clapping Music. Finally, we present a new musical …


A Complex Systems Simulation Study For Increasing Adaptive-Capacity, Kadambari Ram Jan 2017

A Complex Systems Simulation Study For Increasing Adaptive-Capacity, Kadambari Ram

Walden Dissertations and Doctoral Studies

Examination of empirical research confirmed that climate change is a complex problem of anthropological origin and revealed the need for a management framework to facilitate strategic decisions aimed at mitigating a rise in global temperatures of 2-°C linked to irresponsible and unsustainable business practices. The purpose of this simulation study was to develop a management framework of resilience, robustness, sustainability, and adaptive-capacity (RRSA) for organizations viewed as complex systems to address the current unsustainable state. As such, the evolutionary-RRSA prisoner's dilemma (PD) simulation was developed using an evolutionary game theory approach to agent based modeling and simulation, to generate data. …


Coping With Social Complexity Of Infrastructure Projects, Ricardo Peculis Jan 2017

Coping With Social Complexity Of Infrastructure Projects, Ricardo Peculis

SMART Infrastructure Facility - Papers

Infrastructure projects are complex and technical complexity is dwarfed when compared with the social complexity caused by the interaction of individuals and organisations that participate and influence these projects. During conception and planning, uncertainty and conflicting motivations influence decisions that drive the solution and plans that are carried out during construction, operation and finally disposal of the system. If the need is not accurately conveyed and the solution is not properly defined, estimated and planned, infrastructure projects become subject of costs overrun and schedule delays of serious consequences, including the possibility that they may not satisfy the real need. Understanding …