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Dartmouth College

2010

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Articles 1 - 30 of 66

Full-Text Articles in Physical Sciences and Mathematics

Pauli Spin Blockade And Lifetime-Enhanced Transport In A Si/Sige Double Quantum Dot, C. B. Simmons, Teck Seng Koh, Nakul Shaji, Madhu Thalakulam, L. J. Klein, Hua Qin, H. Luo, D. E. Savage, M. G. Lagally, A. J. Rimberg Dec 2010

Pauli Spin Blockade And Lifetime-Enhanced Transport In A Si/Sige Double Quantum Dot, C. B. Simmons, Teck Seng Koh, Nakul Shaji, Madhu Thalakulam, L. J. Klein, Hua Qin, H. Luo, D. E. Savage, M. G. Lagally, A. J. Rimberg

Dartmouth Scholarship

We analyze electron-transport data through a Si/SiGe double quantum dot in terms of spin blockade and lifetime-enhanced transport (LET), which is transport through excited states that is enabled by long spin-relaxation times. We present a series of low-bias voltage measurements showing the sudden appearance of a strong tail of current that we argue is an unambiguous signature of LET appearing when the bias voltage becomes greater than the singlet-triplet splitting for the (2,0) electron state. We present eight independent data sets, four in the forward-bias (spin-blockade) regime and four in the reverse-bias (lifetime-enhanced transport) regime and show that all eight …

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Information-Preserving Structures: A General Framework For Quantum Zero-Error Information, Robin Blume-Kohout, Hui Khoon Ng, David Poulin, Lorenza Viola Dec 2010

Information-Preserving Structures: A General Framework For Quantum Zero-Error Information, Robin Blume-Kohout, Hui Khoon Ng, David Poulin, Lorenza Viola

Dartmouth Scholarship

Quantum systems carry information. Quantum theory supports at least two distinct kinds of information (classical and quantum), and a variety of different ways to encode and preserve information in physical systems. A system’s ability to carry information is constrained and defined by the noise in its dynamics. This paper introduces an operational framework, using information-preserving structures, to classify all the kinds of information that can be perfectly (i.e., with zero error) preserved by quantum dynamics. We prove that every perfectly preserved code has the same structure as a matrix algebra, and that preserved information can always be corrected. We …

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Building Graphs From Colored Trees, Rachel M. Esselstein, Peter Winkler Nov 2010

Building Graphs From Colored Trees, Rachel M. Esselstein, Peter Winkler

Dartmouth Scholarship

We will explore the computational complexity of satisfying certain sets of neighborhood conditions in graphs with various properties. More precisely, fix a radius $\rho$ and let $N(G)$ be the set of isomorphism classes of $\rho$-neighborhoods of vertices of $G$ where $G$ is a graph whose vertices are colored (not necessarily properly) by colors from a fixed finite palette. The root of the neighborhood will be the unique vertex at the "center" of the graph. Given a set S of colored graphs with a unique root, when is there a graph G with N (G) = S? Or N (G) ⊂ …

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Resistive Mhd Reconstruction Of Two-Dimensional Coherent Structures In Space, W L. Teh, B U. Sonnerup, J Birn, R E. Denton Nov 2010

Resistive Mhd Reconstruction Of Two-Dimensional Coherent Structures In Space, W L. Teh, B U. Sonnerup, J Birn, R E. Denton

Dartmouth Scholarship

We present a reconstruction technique to solve the steady resistive MHD equations in two dimensions with initial inputs of field and plasma data from a single space- craft as it passes through a coherent structure in space. At least two components of directly measured electric fields (the spacecraft spin-plane components) are required for the reconstruction, to produce two-dimensional (2-D) field and plasma maps of the cross section of the structure. For con- venience, the resistivity tensor η is assumed diagonal in the reconstruction coordinates, which allows its values to be es- timated from Ohm’s law, E+v×B=η·j. In the present paper, …

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Some Communication Complexity Results And Their Applications, Joshua E. Brody Nov 2010

Some Communication Complexity Results And Their Applications, Joshua E. Brody

Dartmouth College Ph.D Dissertations

Communication Complexity represents one of the premier techniques for proving lower bounds in theoretical computer science. Lower bounds on communication problems can be leveraged to prove lower bounds in several different areas. In this work, we study three different communication complexity problems. The lower bounds for these problems have applications in circuit complexity, wireless sensor networks, and streaming algorithms. First, we study the multiparty pointer jumping problem. We present the first nontrivial upper bound for this problem. We also provide a suite of strong lower bounds under several restricted classes of protocols. Next, we initiate the study of several non-monotone …

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Quantum Equivalent Magnetic Fields That Are Not Classically Equivalent, Carolyn Gordon, William Kirwin, Dorothee Schueth, David Webb Oct 2010

Quantum Equivalent Magnetic Fields That Are Not Classically Equivalent, Carolyn Gordon, William Kirwin, Dorothee Schueth, David Webb

Dartmouth Scholarship

We construct pairs of compact Kähler-Einstein manifolds (Mi,gi,ωi)(i=1,2) of complex dimension n with the following properties: The canonical line bundle Li=⋀nT∗Mi has Chern class [ωi/2π], and for each positive integer k the tensor powers L⊗k1 and L⊗k2 are isospectral for the bundle Laplacian associated with the canonical connection, while M1 and M2 – and hence T∗M1 and T∗M2 – are not homeomorphic. In the context of geometric quantization, we interpret these examples as magnetic fields which are quantum equivalent but not classically equivalent. Moreover, we construct many …

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4-Phenyl­Sulfon­Yl-2-(P-Tolyl­Sulfon­Yl)-1h,8h-Pyrrolo­[2,3-B]Indole, Jeanese C. Badenock, Jason A. Jordan, Erin T. Pelkey, Gordon W. Gribble, Jerry P. Jasinski Oct 2010

4-Phenyl­Sulfon­Yl-2-(P-Tolyl­Sulfon­Yl)-1h,8h-Pyrrolo­[2,3-B]Indole, Jeanese C. Badenock, Jason A. Jordan, Erin T. Pelkey, Gordon W. Gribble, Jerry P. Jasinski

Dartmouth Scholarship

The title compound, C23H18N2O4S2, contains a pyrrolo group fused onto the plane of an indole ring with phenylsulfonyl and p-toluenesulfonyl groups bonded to the indole and pyrrolo rings. The angles between the mean planes of the pyrrolo- indole ring and the phenylsulfonyl and p-toluenesulfonyl rings are 73.7 (6) and 80.6 (0)􏰈, respectively. The dihedral angle between the mean planes of the two benzene rings is 78.7 (4)􏰈. In the crystal, both classical N—H􏰇 􏰇 􏰇O and non-classical C— H􏰇 􏰇 􏰇O intermolecular hydrogen-bonding interactions are observed, as well as weak 􏰁–􏰁 interactions [centroid–centroid distances = 3.6258 (8) and 3.9298 (8) …

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Detecting Photographic Composites Of Famous People, Eric Kee, Hany Farid Oct 2010

Detecting Photographic Composites Of Famous People, Eric Kee, Hany Farid

Computer Science Technical Reports

Photos are commonly falsified by compositing two or more people into a single image. We describe how such composites can be detected by estimating a camera's intrinsic parameters. Differences in these parameters across the image are then used as evidence of tampering. Expanding on earlier work, this approach is more applicable to low-resolution images, but requires a reference image of each person in the photo as they are directly facing the camera. When considering composites of famous people, such a reference photo is easily obtained from an on-line image search.

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The Trilinear Hamiltonian: A Zero-Dimensional Model Of Hawking Radiation From A Quantized Source, Paul D. Nation, Miles P. Blencowe Sep 2010

The Trilinear Hamiltonian: A Zero-Dimensional Model Of Hawking Radiation From A Quantized Source, Paul D. Nation, Miles P. Blencowe

Dartmouth Scholarship

We investigate a quantum parametric amplifier with dynamical pump mode, viewed as a zero-dimensional model of Hawking radiation from an evaporating black hole. We derive the conditions under which the spectrum of particles generated from vacuum fluctuations deviates from the thermal spectrum predicted for the conventional parametric amplifier. We find that significant deviations arise when the pump mode (black hole) has emitted nearly half of its initial energy into the signal (Hawking radiation) and idler (in-falling particle) modes. As a model of black hole dynamics, this finding lends support to the view that late-time Hawking radiation contains information about the …

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Optical Discovery Of An Apparent Galactic Supernova Remnant G159.6+7.3, Robert A. Fesen, Dan Milisavljevic Sep 2010

Optical Discovery Of An Apparent Galactic Supernova Remnant G159.6+7.3, Robert A. Fesen, Dan Milisavljevic

Dartmouth Scholarship

Deep Hα images of portions of a faint 3° × 4° Hα shell centered at l = 1596, b = 73 seen on the Virginia Tech Spectral Line Survey images revealed the presence of several thin emission filaments along its eastern limb. Low-dispersion optical spectra of two of these filaments covering the wavelength range of 4500-7500 Å show narrow Hα line emissions with velocities around –170 ± 30 km s–1. Both the morphology and spectra of these filaments are consistent with a Balmer-dominated shock interpretation and we propose that these optical filaments indicate that the large Hα emission …

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A Correlation Attack Against User Mobility Privacy In A Large-Scale Wlan Network, Keren Tan, Guanhua Yan, Jihwang Yeo, David Kotz Sep 2010

A Correlation Attack Against User Mobility Privacy In A Large-Scale Wlan Network, Keren Tan, Guanhua Yan, Jihwang Yeo, David Kotz

Dartmouth Scholarship

User association logs collected from real-world wireless LANs have facilitated wireless network research greatly. To protect user privacy, the common practice in sanitizing these data before releasing them to the public is to anonymize users' sensitive information such as the MAC addresses of their devices and their exact association locations. In this work,we demonstrate that these sanitization measures are insufficient in protecting user privacy from a novel type of correlation attack that is based on CRF (Conditional Random Field). In such a correlation attack, the adversary observes the victim's AP (Access Point) association activities for a short period of time …

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Empirical Geographic Modeling Of Switchgrass Yields In The United States, Henriette I. Jager, Latha M. Baskaran, Craig C. Brandt, Ethan B. Davis Sep 2010

Empirical Geographic Modeling Of Switchgrass Yields In The United States, Henriette I. Jager, Latha M. Baskaran, Craig C. Brandt, Ethan B. Davis

Dartmouth Scholarship

Switchgrass (Panicum virgatum L.) is a perennial grass native to the United States that has been studied as a sustainable source of biomass fuel. Although many field‐scale studies have examined the potential of this grass as a bioenergy crop, these studies have not been integrated. In this study, we present an empirical model for switchgrass yield and use this model to predict yield for the conterminous United States. We added environmental covariates to assembled yield data from field trials based on geographic location. We developed empirical models based on these data. The resulting empirical models, which account for spatial …

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Out Of The Depths: Image Statistics Of Space, Water, And The Minuscule World, Nimit S. Dhulekar Sep 2010

Out Of The Depths: Image Statistics Of Space, Water, And The Minuscule World, Nimit S. Dhulekar

Dartmouth College Master’s Theses

In images of natural scenes, a consistent relationship exists between spectral power and spatial frequency. The power spectrum falls off with a form 1/f^p as spatial frequency f increases, with values of p approximately equal to 2. To quantify the extent to which this statistical characteristic is exhibited by other classes of images, we examined astronomical, underwater, and microscale images. It was found that this property holds for all three categories of images, although the value of p varies in the range 1.76 to 2.37. The second statistical characteristic computed was the angular spread of the power spectrum. This metric …

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Long-Lived Time-Dependent Remnants During Cosmological Symmetry Breaking: From Inflation To The Electroweak Scale, Marcelo Gleiser, Noah Graham, Nikitas Stamatopoulos Aug 2010

Long-Lived Time-Dependent Remnants During Cosmological Symmetry Breaking: From Inflation To The Electroweak Scale, Marcelo Gleiser, Noah Graham, Nikitas Stamatopoulos

Dartmouth Scholarship

Through a detailed numerical investigation in three spatial dimensions, we demonstrate that long-lived time-dependent field configurations emerge dynamically during symmetry breaking in an expanding de Sitter spacetime. We investigate two situations: a single scalar field with a double-well potential and an SU(2) non-Abelian Higgs model. For the single scalar, we show that large-amplitude oscillon configurations emerge spontaneously and persist to contribute about 1.2% of the energy density of the Universe. We also show that for a range of parameters, oscillon lifetimes are enhanced by the expansion and that this effect is a result of parametric resonance. For the SU(2) case, …

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Perpendicular Ion Heating By Low-Frequency Alfvén-Wave Turbulence In The Solar Wind, Benjamin D. G. Chandran, Bo Li, Barrett N. Rogers, Eliot Quataert, Kai Germaschewski Aug 2010

Perpendicular Ion Heating By Low-Frequency Alfvén-Wave Turbulence In The Solar Wind, Benjamin D. G. Chandran, Bo Li, Barrett N. Rogers, Eliot Quataert, Kai Germaschewski

Dartmouth Scholarship

We consider ion heating by turbulent Alfvén waves (AWs) and kinetic Alfvén waves (KAWs) with wavelengths (measured perpendicular to the magnetic field) that are comparable to the ion gyroradius and frequencies ω smaller than the ion cyclotron frequency Ω. We focus on plasmas in which β < 1, where β is the ratio of plasma pressure to magnetic pressure. As in previous studies, we find that when the turbulence amplitude exceeds a certain threshold, an ion's orbit becomes chaotic. The ion then interacts stochastically with the time-varying electrostatic potential, and the ion's energy undergoes a random walk. Using phenomenological arguments, we derive an analytic expression for the rates at which different ion species are heated, which we test by simulating test particles interacting with a spectrum of randomly phased AWs and KAWs. We find that the stochastic heating rate depends sensitively on the quantity ε = δv ρ/v ⊥, where v ⊥ (v ∥) is the component of the ion velocity perpendicular (parallel) to the background magnetic field B 0, and δv ρ (δB ρ) is the rms amplitude of the velocity (magnetic-field) fluctuations at the gyroradius scale. In the case …

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Numerical Methods For Fmri Data Analysis, Geethmala Sridaran Aug 2010

Numerical Methods For Fmri Data Analysis, Geethmala Sridaran

Dartmouth College Master’s Theses

Brain imaging data are increasingly analyzed via a range of machine-learning methods. In this thesis, we discuss three specific contributions to the field of neuroimaging analysis methods: 1. To apply a recently-developed technique for identifying and viewing similarity structure in neuroimaging data, in which candidate representational structures are ranked; 2. Provide side-by-side analyses of neuroimaging data by a typical non-hierarchical (SVM) versus hierarchical (Decision Tree) machine-learning classification methods; and 3. To develop a novel programming environment for PyMVPA, a current popular analysis toolbox, such that users will be able to type a small number of packaged commands to carry out …

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On Using The Color-Magnitude Diagram Morphology Of M67 To Test Solar Abundances, Z. Magic, A. Serenelli, A. Weiss, B. Chaboyer Aug 2010

On Using The Color-Magnitude Diagram Morphology Of M67 To Test Solar Abundances, Z. Magic, A. Serenelli, A. Weiss, B. Chaboyer

Dartmouth Scholarship

The open cluster M67 has solar metallicity and an age of about 4 Gyr. The turnoff (TO) mass is close to the minimum mass for which solar metallicity stars develop a convective core during main sequence evolution as a result of the development of hydrogen burning through the CNO cycle. The morphology of the color-magnitude diagram (CMD) of M67 around the TO shows a clear hook-like feature, a direct sign that stars close to the TO have convective cores. VandenBerg et al. investigated the possibility of using the morphology of the M67 TO to put constraints on the solar metallicity, …

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Is Bluetooth The Right Technology For Mhealth?, Shrirang Mare, David Kotz Aug 2010

Is Bluetooth The Right Technology For Mhealth?, Shrirang Mare, David Kotz

Dartmouth Scholarship

Many people believe mobile healthcare (mHealth) would help alleviate the rising cost of healthcare and improve the quality of service. Bluetooth, which is the most popular wireless technology for personal medical devices, is used for most of the mHealth sensing applications. In this paper we raise the question – Is Bluetooth the right technology for mHealth? To instigate the discussion we discuss some shortcomings of Bluetooth and also point out an alternative solution.

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On Usable Authentication For Wireless Body Area Networks, Cory Cornelius, David Kotz Aug 2010

On Usable Authentication For Wireless Body Area Networks, Cory Cornelius, David Kotz

Dartmouth Scholarship

We examine a specific security problem in wireless body area networks (WBANs), what we call the ıt one body authentication problem. That is, how can we ensure that the wireless sensors in a WBAN are collecting data about one individual and not several individuals. We explore existing solutions to this problem and provide some analysis why these solutions are inadequate. Finally, we provide some direction towards a promising solution to the problem and how it can be used to create a usably secure WBAN.

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Can I Access Your Data? Privacy Management In Mhealth, Aarathi Prasad, David Kotz Aug 2010

Can I Access Your Data? Privacy Management In Mhealth, Aarathi Prasad, David Kotz

Dartmouth Scholarship

Mobile health (mHealth) has become important in the field of healthcare information technology, as patients begin to use mobile medical sensors to record their daily activities and vital signs. Since their medical data is collected by their sensors, the patients may wish to control data collection and distribution, so as to protect their data and share it only when the need arises. It must be possible for patients to grant or deny access to the data on the storage unit (mobile phones or personal health records (PHR)). Thus, an efficient framework is required for managing patient consent electronically, i.e.to allow …

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The First Vlbi Image Of The Young, Oxygen-Rich Supernova Remnant In Ngc 4449, M. F. Bietenholz, N. Bartel, D. Milisavljevic, R. A. Fesen Jul 2010

The First Vlbi Image Of The Young, Oxygen-Rich Supernova Remnant In Ngc 4449, M. F. Bietenholz, N. Bartel, D. Milisavljevic, R. A. Fesen

Dartmouth Scholarship

We report on sensitive 1.4-GHz VLBI radio observations of the unusually luminous supernova remnant SNR 4449-1 in the galaxy NGC 4449, which gave us the first well-resolved image of this object. The remnant's radio morphology consists of two approximately parallel bright ridges, suggesting similarities to the barrel shape seen for many older Galactic supernova remnants or possibly to SN 1987A. The angular extent of the remnant is 65 × 40 mas, corresponding to (3.7 × 2.3) × 1018 (D/3.8 Mpc) cm. We also present a new, high signal-to-noise ratio optical spectrum. By comparing the remnant's linear size …

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Sn 2010u: A Luminous Nova In Ngc 4214, Roberta M. Humphreys, José L. Prieto, Philip Rosenfield, L. Andrew Helton, Christopher S. Kochanek, K. Z. Stanek, Rubab Khan, Dorota Szczygiel, Karen Mogren, Robert A. Fesen Jul 2010

Sn 2010u: A Luminous Nova In Ngc 4214, Roberta M. Humphreys, José L. Prieto, Philip Rosenfield, L. Andrew Helton, Christopher S. Kochanek, K. Z. Stanek, Rubab Khan, Dorota Szczygiel, Karen Mogren, Robert A. Fesen

Dartmouth Scholarship

The luminosity, light curve, post-maximum spectrum, and lack of a progenitor on deep pre-outburst images suggest that SN 2010U was a luminous, fast nova. Its outburst magnitude is consistent with that for a fast nova using the maximum magnitude-rate of decline relationship for classical novae.

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Colours Of Bulges And Discs Within Galaxy Clusters And The Signature Of Disc Fading On Infall, Michael J. Hudson, Jeffrey B. Stevenson, Russell J. Smith, Gary A. Wegner Jul 2010

Colours Of Bulges And Discs Within Galaxy Clusters And The Signature Of Disc Fading On Infall, Michael J. Hudson, Jeffrey B. Stevenson, Russell J. Smith, Gary A. Wegner

Dartmouth Scholarship

The origins of the bulge and disc components of galaxies are of primary importance to understanding galaxy formation. Here bulge–disc decomposition is performed simultaneously in B and R bands for 922 bright galaxies in eight nearby (z < 0.06) clusters with deep redshift coverage using photometry from the National Optical Astronomy Observatory (NOAO) Fundamental Plane Survey. The total galaxy colours follow a universal colour–magnitude relation (CMR). The discs of L* galaxies are 0.24 mag bluer in B−R than bulges. Bulges have a significant CMR slope while the CMR slope of discs is flat. Thus the slope of the CMR of the total light is driven primarily (60 per cent) by the bulge CMR, and to a lesser extent (40 per cent) by the change in the bulge‐to‐total ratio …

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Ice Layers As An Indicator Of Summer Warmth And Atmospheric Blocking In Alaska, Eric P. Kelsey, Cameron P. Wake, Karl Kreutz, Erich Osterberg Jun 2010

Ice Layers As An Indicator Of Summer Warmth And Atmospheric Blocking In Alaska, Eric P. Kelsey, Cameron P. Wake, Karl Kreutz, Erich Osterberg

Dartmouth Scholarship

No abstract provided.

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Stirring Up The Pot: Can Cooling Flows In Galaxy Clusters Be Quenched By Gas Sloshing?, J. A. A. Zuhone, M. Markevitch, R. E. Johnson Jun 2010

Stirring Up The Pot: Can Cooling Flows In Galaxy Clusters Be Quenched By Gas Sloshing?, J. A. A. Zuhone, M. Markevitch, R. E. Johnson

Dartmouth Scholarship

X-ray observations of clusters of galaxies reveal the presence of edges in surface brightness and temperature, known as "cold fronts." In relaxed clusters with cool cores, these commonly observed edges have been interpreted as evidence for the "sloshing" of the core gas in the cluster's gravitational potential. Such sloshing may provide a source of heat to the cluster core by mixing hot gas from the cluster outskirts with the cool-core gas. Using high-resolution N-body/Eulerian hydrodynamic simulations, we model gas sloshing in galaxy clusters initiated by mergers with subclusters. The simulations include merger scenarios with gas-filled and gasless subclusters. The …

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Testing General Relativity With Current Cosmological Data, Scott F. Daniel, Eric V. Linder, Tristan L. Smith, Robert R. Caldwell Jun 2010

Testing General Relativity With Current Cosmological Data, Scott F. Daniel, Eric V. Linder, Tristan L. Smith, Robert R. Caldwell

Dartmouth Scholarship

Deviations from general relativity, such as could be responsible for the cosmic acceleration, would influence the growth of large-scale structure and the deflection of light by that structure. We clarify the relations between several different model-independent approaches to deviations from general relativity appearing in the literature, devising a translation table. We examine current constraints on such deviations, using weak gravitational lensing data of the CFHTLS and COSMOS surveys, cosmic microwave background radiation data of WMAP5, and supernova distance data of Union2. A Markov chain Monte Carlo likelihood analysis of the parameters over various redshift ranges yields consistency with general relativity …

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On Arc-Polarized Structures In The Solar Wind, B U. Sonnerup, S E. Haaland, G Paschmann Jun 2010

On Arc-Polarized Structures In The Solar Wind, B U. Sonnerup, S E. Haaland, G Paschmann

Dartmouth Scholarship

A theoretical model is proposed to account for some of the behavior of arc-polarized magnetic structures seen in the solar wind. To this end, an exact analytical solu- tion is developed that describes infinite plane wave trains of arbitrary amplitude in a plasma governed by ideal Hall MHD. The main focus is on intermediate-mode wave trains, which display double-branched magnetic hodogram signatures sim- ilar to those seen in the solar wind. The theoretically derived hodograms have field rotation in the ion-polarized sense at a slightly depressed field magnitude on one branch and an electron-polarized rotation at a slightly enhanced field …

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Virtual Container Attestation: Customized Trusted Containers For On-Demand Computing., Katelin A. Bailey Jun 2010

Virtual Container Attestation: Customized Trusted Containers For On-Demand Computing., Katelin A. Bailey

Dartmouth College Undergraduate Theses

In today's computing environment, data is moving to central locations and most computers are merely used to access the data. Today is the era of cloud computing and distributed computing, where users have control over neither data nor computation. As this trend continues there is an increasing frequency of mutually distrustful parties being forced to interact and share resources with each other in potentially dangerous situations. Therefore, there is an urgent need for a means of creating trust between two entities, or at the very least providing some means of determining the trust level of a given machine. Current approaches …

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Non-Gaussianity From Self-Ordering Scalar Fields, Daniel G. Figueroa, Robert R. Caldwell, Marc Kamionkowski Jun 2010

Non-Gaussianity From Self-Ordering Scalar Fields, Daniel G. Figueroa, Robert R. Caldwell, Marc Kamionkowski

Dartmouth Scholarship

The Universe may harbor relics of the post-inflationary epoch in the form of a network of self-ordered scalar fields. Such fossils, while consistent with current cosmological data at trace levels, may leave too weak an imprint on the cosmic microwave background and the large-scale distribution of matter to allow for direct detection. The non-Gaussian statistics of the density perturbations induced by these fields, however, permit a direct means to probe for these relics. Here we calculate the bispectrum that arises in models of self-ordered scalar fields. We find a compact analytic expression for the bispectrum, evaluate it numerically, and provide …

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Creating Large Disturbances In The Power Grid: Methods Of Attack After Cyber Infiltration, Loren D. Sands-Ramshaw Jun 2010

Creating Large Disturbances In The Power Grid: Methods Of Attack After Cyber Infiltration, Loren D. Sands-Ramshaw

Dartmouth College Undergraduate Theses

Researchers are pursuing methods of securing the cyber aspect of the U.S. power grid, one of the country's most critical infrastructures. An attacker who is able to infiltrate an Energy Management System (EMS) can instruct elements of the grid to function improperly or can skew the state information received by the control programs or operators. In addition, a cyber attack can combine multiple attacks and affect many physical locations at once. A study of the possible adverse effects an attack could generate can underline the urgency of improving grid security, contribute to a roadmap and priority list for security researchers, …

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