Parallel Suffix Sorting, Natsuhiko Futamura, Srinivas Aluru, Stefan Kurtz

Electrical Engineering and Computer Science - All Scholarship

We present a parallel algorithm for lexicographically sorting the suffixes of a string. Suffix sorting has applications in string processing, data compression and computational biology. The ordered list of suffixes of a string stored in an array is known as Suffix Array, an important data structure in string processing and computational biology. Our focus is on deriving a practical implementation that works well for typical inputs rather than achieving the best possible asymptotic running-time for artificial, worst-case inputs. We experimentally evaluated our algorithm on an IBM SP-2 using genomes of several organisms. Our experiments show that the algorithm delivers good, …

Jobqueue: A Computational Grid-Wide Queuing System, Dimitros Katramatos, Marty Humphrey, Andrew Grimshaw, Steve Chapin

Electrical Engineering and Computer Science - All Scholarship

In a Computational Grid, it is not easy to maintain grid-wide control over the number of executing jobs, as well as a global view of the status of submitting jobs, due to the heterogeneity in resource type, availability, and access policies. This paper describes the design and implementation of JobQueue, which is a Computational Grid-wide queuing system, or metaqueuing system, implemented in Legion. JobQueue is unique because of its ability to span multiple administrative domains. It can also be reconfigured dynamically along a number of dimensions and in the general case does not require special privileges to create, facilitating new …

Time-Domain Electric-Field Integral Equation With Central Finite Difference, Baek Ho Jung, Tapan Kumar Sarkar

Electrical Engineering and Computer Science - All Scholarship

In this paper, we present a new formulation using the time-domain electric-field integral equation (TD-EFIE) to obtain a transient scattering response from arbitrarily shaped conducting bodies. The time derivative of the magnetic vector potential is approximated with a central finite difference, and the scalar potential is time averaged by dividing it into two terms. This approach with an implicit method using central-difference results in accurate and stable transient scattering responses from conducting objects. Detailed mathematical steps are included, and several numerical results are presented.

A "Converse" Of The Banach Contraction Mapping Theorem, Pascal Hitzler, Anthony K. Seda

Computer Science and Engineering Faculty Publications

We prove a type of converse of the Banach contraction mapping theorem for metric spaces: if X is a T₁ topological space and f: X -> X is a function with the unique fixed point a such that fⁿ(x) converges to a for each x is a member of X, then there exists a distance function d on X such that f is a contraction on the complete ultrametric space (X,d) with contractivity factor 1/2. We explore properties of the resulting space (X,d).

Generalized Metrics And Topology In Logic Programming Semantics, Pascal Hitzler

Computer Science and Engineering Faculty Publications

Many fixed-point theorems are essentially topological in nature. Among them are the Banach contraction mapping theorem on metric spaces and the fixed-point theorem for Scott-continuous mappings on complete partial orders. The latter theorem is fundamental in denotational semantics since semantic operators in most programming language paradigms satisfy its requirements. The use of negation in logic programming and non-monotonic reasoning, however, renders some semantic operators to be non-monotonic, hence discontinuous with respect to the Scott topology, and therefore invalidates the standard approach, so that alternative methods have to be sought. In this thesis, we investigate topological methods, including generalized metric fixed-point …

Evolution Of Topology In Axi-Symmetric And 3-D Viscous Flows, Gerik Scheuermann, W. Kollmann, Xavier Tricoche, Thomas Wischgoll

Computer Science and Engineering Faculty Publications

No abstract provided.

Coal Availability In Western Kentucky, Gerald A. Weisenfluh, William M. Andrews Jr., Robert E. Andrews, John K. Hiett

Report of Investigations--KGS

Fourteen quadrangles in five separate areas of the Western Kentucky Coal Field were studied to determine what factors affect the availability of coal for mining. Each study area consisted of at least two adjacent 7.5-minute quadrangles in order to account for the geologic variability across broad distances in western Kentucky, and determine how this variability affects availability. Areas both north and south of the Rough Creek Fault System were selected to measure the effect of different geologic, structural, and overburden settings on coal availability. The study emphasized the coals occurring stratigraphically between the Springfield and the Baker.

About 90 percent …

Hydrogeologic Conditions Around Deep Aeration Lagoons At The Bardstown Wastewater Treatment Plant, David R. Wunsch, Gregory L. Secrist, Lyle V.A. Sendlein

Report of Investigations--KGS

The hydrogeologic conditions around the Bardstown Sewage Treatment Plant were studied from August 1996 through December 1997. Hydraulic and geochemical data were collected from eight monitoring wells and four surface-water monitoring sites on the plant property.

There is a large hydraulic gradient between the lagoons at the plant and the surrounding stream, Town Creek. Initial water-level measurements in wells surrounding the site suggest no major leakage from the lagoons, however. Neither flowing artesian conditions nor unusually high water levels were observed in any of the wells. Water-level measurements collected by data loggers showed that shallow wells responded quickly to recharge, …

Physiographic Diagram Of Kentucky, Kentucky Geological Survey

Map and Chart--KGS

No abstract provided.

Ambiguity-Directed Sampling For Qualitative Analysis Of Sparse Data From Spatially-Distributed Physical Systems, Chris Bailey-Kellogg, Naren Ramakrishnan

Computer Science Technical Reports

A number of important scientific and engineering applications, such as fluid dynamics simulation and aircraft design, require analysis of spatially-distributed data from expensive experiments and complex simulations. In such data-scarce applications, it is advantageous to use models of given sparse data to identify promising regions for additional data collection. This paper presents a principled mechanism for applying domain-specific knowledge to design focused sampling strategies. In particular, our approach uses ambiguities identified in a multi-level qualitative analysis of sparse data to guide iterative data collection. Two case studies demonstrate that this approach leads to highly effective sampling decisions that are also …

A Kinetic Study Of The Photolysis Of Tris(2,4-Pentanedionato)Cobalt(Iii) And Bis(2,4-Pentanedionato)Cobalt(Ii) In Chloroform, Son L. Phan, Keith J. Cendak, Patrick E. Hoggard

Chemistry and Biochemistry

Under 254nm irradiation in chloroform, Co(acac)₃ (Hacac = 2,4-pentanedione) is converted to Co(acac)₂ and then to CoCl₂. The metal complex is the primary photoactive species in the photoreduction of Co(acac)₃, but the photosubstitution of Co(acac)₂ appears to occur primarily through absorption of light by the solvent, followed by a chain reaction in which chlorine atoms displace pentanedionyl radicals. The photosubstitution rate law is complex, and the apparent quantum yield (based on total light absorbed) varies with incident light intensity and Co(acac)₂ concentration, reaching values as high as 16 under the conditions of …

Santa Clara Magazine, Volume 43 Number 3, Winter 2001, Santa Clara University

Santa Clara Magazine

4 - UNIVERSITY RESPONDS TO TRAGEDY By SCM Staff. The September terrorist attacks had many repercussions at SCU, including the loss of at least two members of the University family.

12 - BEERS AND DOGS By Adam Breen. English Professor Terry Beers and his wife, Melissa '88, MBA '95, spend many early mornings sledding with their eight huskies.

14 - CALIFORNIA DREAMERS By Susan Vogel. Three current SCU students were dreaming of college long before many people do, thanks to dedicated mentors from the I Have A Dream Foundation .

Awards And Recognition, Iowa Academy Of Science, 2001

Journal of the Iowa Academy of Science: JIAS

No abstract provided.

Lessons From An Inventory Of The Ames, Iowa, Flora (1859-2000), William R. Norris, Deborah Q. Lewis, Mark P. Widrlechner, Jimmie D. Thompson, Richard O. Pope

Journal of the Iowa Academy of Science: JIAS

A botanical survey of the vascular flora of the "planning and zoning jurisdiction" of the city of Ames, Iowa (i.e., the area within a boundary 3.2 km beyond the current city limits) was compiled from 1990 to 2000. During this survey, 916 taxa (71 % native) were encountered within chis boundary. Literature reviews and a survey of Iowa State University's Ada Hayden Herbarium for specimens that had been collected in Ames since 1859 add 204 taxa to the flora. This total of 1,120 taxa exceeds the number of taxa known from any comparable area (including counties) in Iowa. We produced …

Development Of The Continuously Variable Volume Reactor For Use In Flow Injection Analysis, Elizabeth H. Medeiros, C Chad Harrell, Linda L. Lipe, Suzanne M. Purinton

All Volumes (2001-2008)

Recognizing a need for an improved mixer/reactor, the continuously variable volume reactor (CVVR) was developed to address the need for remote unattended FIA manifold operation and the issue of manifold optimization. Development of the CVVR allows fully automated FIA analysis, and through its design allows the volume of the mixing coil to be changed dynamically as the sample bolus travels through the mixing coil to the detector. This is the first time this approach has been demonstrated in the literature.

Projecting Chromatic Aberrations, David L. Gibbs Jr., Phil Ryan, Jay S. Huebner

All Volumes (2001-2008)

The chromatic aberration of lenses is a popular topic in introductory astronomy 1-4 and physics and is readily demonstrated on an optical bench to several students at a time. However, we are not aware of any published descriptions of demonstrations showing chromatic aberration that are useful for large lecture classes. This note describes a simple method of using an overhead projector and an extra lens for displaying chromatic aberrations in large lecture halls so it can be viewed by large audiences.

Micro-Rockets For The Classroom, Alice S. Fletcher, Julia A. Cato, Jennifer A. Barrett, Jay S. Huebner

All Volumes (2001-2008)

Many people are fascinated with rocketry, as evidenced by hundreds of thousands of visitors to the Kennedy Space Center for Space Shuttle launches. Rockets demonstrate important basic principles of chemistry, engineering, and physics 1-5. Even model rockets are exciting to launch. Many physics teachers take advantage of this and use model solid fuel, 6 - 10 and water rockets 11-14 in their teaching activities. Scientific supply companies have responded to this interest and offer a range of equipment to investigate model rocket performance. 6,10,12,15 This note describes miniature solid fuel, or micro rockets, which are made from a single safety …

Parallel Detection Of Closed Streamlines In Planar Flows, Thomas Wischgoll, Gerik Scheuermann, Hans Hagen

Computer Science and Engineering Faculty Publications

No abstract provided.

Unique Supported-Model Classes Of Logic Programs, Pascal Hitzler, Anthony K. Seda

Computer Science and Engineering Faculty Publications

We study classes of programs, herein called unique supported-model classes, with the property that each program in the class has a unique supported model. Elsewhere, the authors examined these classes from the point of view of operators defined relative to certain three-valued logics. In this paper, we complement our earlier results by considering how unique supported-model classes fit into the framework given by various classes of programs in several well-known approaches to semantics.

Kontraktionssatze Auf Verallgemeinerten Metrischen Raumen, Pascal Hitzler

Computer Science and Engineering Faculty Publications

Long‐Term Vri Photometry Of Small‐Amplitude Red Variables. I. Light Curves And Periods, John R. Percy, Joseph B. Wilson, Gregory W. Henry

Information Systems and Engineering Management Research Publications

We report up to 5000 days of VRI photometry, from a robotic photometric telescope, of 34 pulsating red giants, namely, TV Psc, EG And, Z Psc, RZ And, 4 Ori, RX Lep, UW Lyn, η Gem, μ Gem, ψ¹ Aur, V523 Mon, V614 Mon, HD 52690, Y Lyn, BC CMi, X Cnc, UX Lyn, RS Cnc, VY UMa, ST UMa, TU CVn, FS Com, SW Vir, 30 Her, α¹ Her, V642 Her, R Lyr, V450 Aql, V1293 Aql, δ Sge, EU Del, V1070 Cyg, W Cyg, and μ Cep, as well as a few variable comparison stars. V …

10 New Γ Doradus And Δ Scuti Stars, Gregory W. Henry, Francis C. Fekel, Anthony B. Kaye, Ann Kaul

Information Systems and Engineering Management Research Publications

We present high-resolution spectroscopy and precision photometry of five new γ Doradus and five new δ Scuti variables. The five new γ Doradus variables substantially increase the number of confirmed stars of this class. All 10 stars fall in the spectral class range F0–F2, but they are cleanly separated into two groups by their luminosity and photometric periods. However, the period gap between the γ Doradus and δ Scuti stars is becoming very narrow since we confirm that HD 155154 is a γ Doradus star with the shortest periods reported to date (the shortest of its four periods is ∼0.312 …

Development Of Equilibrium After Preheating, Gary Felder, Lev Kofman

Physics: Faculty Publications

We present a fully nonlinear study of the development of equilibrium after preheating. Preheating is the exponentially rapid transfer of energy from the nearly homogeneous inflaton field to fluctuations of other fields and/or the inflaton itself. This rapid transfer leaves these fields in a highly nonthermal state with energy concentrated in infrared modes. We have performed lattice simulations of the evolution of interacting scalar fields during and after preheating for a variety of inflationary models. We have formulated a set of generic rules that govern the thermalization process in all of these models. Notably, we see that once one of …

Quantum Confinement Transition In A D-Wave Superconductor, Courtney Lannert, T. Senthil, Matthew P. Fisher

Physics: Faculty Publications

We study the nature of the zero-temperature phase transition between a d-wave superconductor and a Mott insulator in two dimensions. In this "quantum confinement transition", spin and charge are confined to form the electron in the Mott insulator. Within a dual formulation, direct transitions from d-wave superconductors at half-filling to insulators with spin-Peierls (as well as other) order emerge naturally. The possibility of striped superconductors is also discussed within the dual formulation. The transition is described by nodal fermions and bosonic vortices, interacting via a long-ranged statistical interaction modeled by two coupled Chern-Simons gauge fields, and the critical properties of …

Electron Spectral Function In Two-Dimensional Fractionalized Phases, Courtney Lannert, Matthew P.A. Fisher, T. Senthil

Physics: Faculty Publications

We study the electron spectral function of various zero-temperature spin-charge separated phases in two dimensions. In these phases, the electron is not a fundamental excitation of the system, but rather “decays” into a spin-1/2 chargeless fermion (the spinon) and a spinless charge e boson (the chargon). Using low-energy effective theories for the spinons (d-wave pairing plus possible Néel order) and the chargons (condensed or quantum-disordered bosons), we explore three phases of possible relevance to the cuprate superconductors: (1) (formula presented) a fractionalized antiferromagnet where the spinons are paired into a state with long-ranged Néel order and the chargons are 1/2-filled …

Biharmonic Maps On V-Manifolds, Yuan-Jen Chiang, Hongan Sun

Mathematics

We generalize biharmonic maps between Riemannian manifolds into the case of the domain being V-manifolds. We obtain the first and second variations of biharmonic maps on V-manifolds. Since a biharmonic map from a compact V-manifold into a Riemannian manifold of nonpositive curvature is harmonic, we construct a biharmonic non-harmonic map into a sphere. We also show that under certain condition the biharmonic property of f implies the harmonic property of f. We finally discuss the composition of biharmonic maps on V-manifolds.

Local Search And Encoding Schemes For Soft Constraint Minimization Problems, Michael P. Moran, Weixiong Zhang

All Computer Science and Engineering Research

Soft constraint minimization problems (SCMPs) contain hard constraints that cannot be violated and soft constraints that may be violated but carry penalties if not satisfied. In this paper, we first extend local search, WalkSAT in particular, to SCMPs and study the existing SAT encoding schemes for SCMPs. We propose a general encoding method called k-encoding. We then investigate the effects of local search neiborhood structures introduced by encoding schemes and analyze the anytime performance of extended WalkSAT using different encoding methods. Our experimental results on various graph coloring problems show that a direct extension of WalkSAT is most effective, and …

Formal Specification And Design Of Mobile Systems, Gruia-Catalin Roman, Christine Julien, Qingfeng Huang

All Computer Science and Engineering Research

Termination detection, a classical problem in distributed computing, is revisited in the new setting provided by the emerging mobile computing technology. A simple solution tailored for use in ad hoc networks is employed as a vehicle for demonstrating the applicability of formal requirements and design strategies to the new field of mobile computing. The approach is based on well understood techniquest in specification refinement, but the methodology is tailored to mobile applications and helps designers address novel concerns such as the mobility of hosts, transient interactions, and specific coordination constructs. The proof logic and programming notation of Mobile UNITY provide …

Obiwan - An Internet Protocol Router In Reconfigurable Hardware, Florian Braun, Marcel Waldvogel, John Lockwood

All Computer Science and Engineering Research

The ongoing exponential increase of line speed in the Internet and combined with the uncountable requests for increased functionality of network devices presents a major challenge. These demands call for the use of reprogrammable hardware to provide the required flexible high-speed functionaltiy. The Field Programmable Port Extender (FPX) provides such an environment for development of networking components in reprogrammable hardware. We present the high-speed IP routing components in reprogrammable hardware. We present the high-speed IP routing module "OBIWAN" (Optimal Binary search IP lookup for Wide Area Networks) built on top of an IP processing framework.

Phase Transitions And Backbones Of Constraint Minimization Problems, Weixiong Zhang

All Computer Science and Engineering Research

Many real-world problems involve constraints that cannot be all satisfied. The goal toward an overconstrained problem is to find solutions minimizing the total number of constraints violated. We call such a problem constraint minimization problem (CMP). We study the behavior of the phase transitions and backbones of CMP. We first investigate the relationship between the phase transitions of Boolean satisfiability, or precisely 3-SAT (a well-studied NP-complete decision problem), and the phase transitions of MAX 3-SAT (an NP-hard optimization problem). To bridge the gap between the easy-hard-easy phase transitions of 3-SAT, in which solutions of bounded quality, e.g., solutions with at …