In the Firefighter Problem, a fire starts at a vertex of a graph, and in discrete time units, it spreads from burned vertices to their neighbors, unless they are protected by one of the f firefighters that are deployed every turn. Once burned or...
We present new forensic tools that are capable of detecting traces of tampering in digital images without the use of watermarks or specialized hardware. These tools operate under the assumption that images contain natural properties from a variety...
The Euler '-function and Carmichael -function are extremely important in modern number theory, and much work has been devoted to studying the distribution and arithmetic properties of the values of each function. One interesting unresolved question...
This thesis investigates a notion of Turing reducibility introduced by Winkler [8] that is total on all computably enumerable oracles. Groszek and Weber show in [7] that this is a new notion of reducibility and it is not transitive. They give su...
We start by introducing avoidance coupling of Markov chains, with an overview of existing results. We then introduce and motivate a new notion, uniform coupling. We show that the only Markovian avoidance coupling on a cycle is of this type, and...
Electronic data processing -- Distributed processing. ; Computer network architectures. ; Programming languages (Electronic computers) -- Semantics. ; Database management.
I tackle the problem of naming and sharing resources across administrative boundaries. Conventional systems manifest the hierarchy of typical administrative structure in the structure of their own mechanism. While natural for communication that...
Space perception. ; Motion perception (Vision). ; Vestibular apparatus.
Head Direction (HD) cells are neurons located primarily in the limbic system that fire as a function of directional heading in the horizontal, or yaw, plane in the freely moving animal. Our hypothesis is that the HD signal is the result of two...
Dipterocarpaceae -- Ecology -- Indonesia -- Kalimantan Barat. ; Rain forest ecology -- Indonesia -- Kalimantan Barat. ; Herbivores -- Ecology.
A decline in population growth as the abundance of a species increases can stabilize population size. In Western Borneo, I found evidence for such density dependence in juveniles of the genus Shorea (Dipterocarpaceae) that dominates southeast...
Core binding factor (CBF) is a heterodimeric transcription factor that is essential for a number of developmental process including hemotopoiesis and bone development. CBFs contain a DNA-binding CBFα. subunit and a non-DNA binding CBFß. subunit...
Identifying and understanding sources of individual variation in fecundity is of central importance to life history theory and population ecology. In this study, I first examined how factors on the breeding grounds in eastern Maryland affected the...
We present designs, theory and the results of fabrication and testing for a novel parallel microrobotic assembly scheme using stress-engineered MEMS microrobots. The robots are 240-280 μm × 60 μm × 7-20 μm in size, each robot consist of a...
This thesis contains some results concerning groupoid dynamical systems and crossed products. We introduce the notion of a proper groupoid dynamical system and of its generalized fixed point algebra. We show that our notion of proper groupoid...
Macrocyclic tetrapyrroles are essential to life. In nature, they play important roles in living organisms, such as oxygen transportation and photosynthesis. Pentynoic acids are versatile precursors for preparing pyrrolines and higher homologues....
Graph algorithms. Nuclear magnetic resonance spectroscopy -- Data processing. Proteins -- Structure -- Mathematical models. Proteins -- Crosslinking -- Mathematical models. Protein folding -- Mathematical models.
The study of three-dimensional protein structures produces insights into protein function at the molecular level. Graphs provide a natural representation of protein structures and associated experimental data, and enable the development of graph...
Magnetosphere -- Mathematical models. Magnetic reconnection -- Mathematical models.
In this thesis we present the results of two studies of magnetic reconnection at the dayside magnetopause using the Lyon-Fedder-Mobarry magnetospheric simulation code. The first study examined the global properties of reconnection as a function of...
Manifolds (Mathematics) Geodesics (Mathematics) Space and time.
We investigate weak and strong refocusing of light rays in a space-time and related concepts. A strongly causal space-time ( X^ n +1 , g ) is emphstrongly refocusing at x ∈ X if there is a point y ≠ x such that all null-geodesics through y pass...
Autonomous off-road navigation in unstructured, terrain can encounter mobility difficulties even when the surface that the vehicle is driving over is level and free from obstacles. Mobility challenges result from soil characteristics that prevent...
Despite great progress in object recognition techniques, there is a mismatch between traditional approaches and the characteristics of real world vision tasks. We highlight in particular, three closely related areas of mismatch: i) recognition...
It is never an easy task to make reasonable decisions on how people should act to preserve natural resources and to have various stakeholders agree with such decisions. This difficulty arises for a number of reasons, including: (1) the existence of...
Magnetic resonance elastography (MRE) is a recently developed imaging modality that measures and visualizes the mechanical properties of tissue in vivo. One of the essential reconstruction procedures in MRE is motion estimation. For dynamic...