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Articles 2851 - 2880 of 3095

Full-Text Articles in Physical Sciences and Mathematics

Recent Global Warming: A New Approach To Interpreting Some Of The Data, Stanley Schleifer, Nazrul I. Khandaker, Samuel Borenstein, Che-Tsao Huang, Thakur Chaturgan, Feng Chan Liang, Mario Jo-Ramirez, Dorean J. Flores, Poonraj Persaud, Selwyn N. Lebourne Sep 2006

Recent Global Warming: A New Approach To Interpreting Some Of The Data, Stanley Schleifer, Nazrul I. Khandaker, Samuel Borenstein, Che-Tsao Huang, Thakur Chaturgan, Feng Chan Liang, Mario Jo-Ramirez, Dorean J. Flores, Poonraj Persaud, Selwyn N. Lebourne

Publications and Research

The authors have done an analysis of meteorological data which may add to the growing body of information addressing the cause or causes of recent global warming. If an augmented greenhouse effect, due to increasing atmospheric carbon dioxide concentrations, has been a significant factor producing global warming, then this should be indicated by an increase in the interval of time between the time of maximum insolation, and the time of maximum surface temperature, as well as a decrease in the interval of time between the time of minimum insolation and the time of minimum surface temperature, in the mid latitudes. …


Reducing Price Fluctuation In Continuous Double Auctions Through Pricing Policy And Shout Improvement, Jinzhong Niu, Kai Cai, Simon Parsons, Elizabeth Sklar May 2006

Reducing Price Fluctuation In Continuous Double Auctions Through Pricing Policy And Shout Improvement, Jinzhong Niu, Kai Cai, Simon Parsons, Elizabeth Sklar

Publications and Research

Auction mechanism design is a subfield of game theory dedicated to manipulating the rules of an auction so as to achieve specific goals. The complexity of the dynamics of auctions, especially continuous double auctions, makes it difficult to apply the usual analytic game-theoretic methods. This paper takes an experimental approach, searching a parameterized space of possible auction types, and presents a new pricing policy for continuous double auctions. The paper further demonstrates how this policy, together with a shout improvement rule, helps to reduce the fluctuation of transaction prices in auctions involving agents with minimum intelligence while keeping the overall …


A Remark On Conservative Diffeomorphisms, Jairo Bochi, Bassam R. Fayad, Enrique Pujals Apr 2006

A Remark On Conservative Diffeomorphisms, Jairo Bochi, Bassam R. Fayad, Enrique Pujals

Publications and Research

Abstract:

We show that a stably ergodic diffeomorphism can be C1 approximated by a diffeomorphism having stably non-zero Lyapunov exponents.

Résumé:

On montre qu'un difféomorphisme stablement ergodique peut être C1 approché par un difféomorphisme ayant des exposants de Lyapunov stablement non-nuls.


Tr-2006003: Explicit Proofs In Formal Provability Logic, Evan Goris Jan 2006

Tr-2006003: Explicit Proofs In Formal Provability Logic, Evan Goris

Computer Science Technical Reports

No abstract provided.


Tr-2006007: Root-Finding With Eigen-Solving, Victor Y. Pan, Brian Murphy, Rhys Eric Rosholt Jan 2006

Tr-2006007: Root-Finding With Eigen-Solving, Victor Y. Pan, Brian Murphy, Rhys Eric Rosholt

Computer Science Technical Reports

No abstract provided.


Tr-2006008: Every P-Recursion Category Has An Index Composer, Florian Lengyel Jan 2006

Tr-2006008: Every P-Recursion Category Has An Index Composer, Florian Lengyel

Computer Science Technical Reports

No abstract provided.


Tr-2006005: Logical Omniscience Via Proof Complexity, Sergei Artemov, Roman Kuznets Jan 2006

Tr-2006005: Logical Omniscience Via Proof Complexity, Sergei Artemov, Roman Kuznets

Computer Science Technical Reports

No abstract provided.


Tr-2006006: Additive Preconditioning And Aggregation In Matrix Computations, Victor Y. Pan, Dmitriy Ivolgin, Brian Murphy, Rhys Eric Rosholt, Islam Taj-Eddin, Yuqing Tang, Xiaodong Yan Jan 2006

Tr-2006006: Additive Preconditioning And Aggregation In Matrix Computations, Victor Y. Pan, Dmitriy Ivolgin, Brian Murphy, Rhys Eric Rosholt, Islam Taj-Eddin, Yuqing Tang, Xiaodong Yan

Computer Science Technical Reports

No abstract provided.


Tr-2006012: Every P-Recursion Category Has An Index Composer, Florian Lengyel Jan 2006

Tr-2006012: Every P-Recursion Category Has An Index Composer, Florian Lengyel

Computer Science Technical Reports

No abstract provided.


Tr-2006001: The Em Algorithm As A Lower Bound Optimization Technique, Rave Harpaz, Robert Haralick Jan 2006

Tr-2006001: The Em Algorithm As A Lower Bound Optimization Technique, Rave Harpaz, Robert Haralick

Computer Science Technical Reports

No abstract provided.


Tr-2006002: A Replacement Theorem For Lp, Melvin Fitting Jan 2006

Tr-2006002: A Replacement Theorem For Lp, Melvin Fitting

Computer Science Technical Reports

No abstract provided.


Tr-2006004: Justified Knowledge Is Sufficient, Evangelia Antonakos Jan 2006

Tr-2006004: Justified Knowledge Is Sufficient, Evangelia Antonakos

Computer Science Technical Reports

No abstract provided.


Tr-2006011: Locally Connected Recursion Categories, Florian Lengyel Jan 2006

Tr-2006011: Locally Connected Recursion Categories, Florian Lengyel

Computer Science Technical Reports

No abstract provided.


Tr-2006013: The Dom Event And Its Use In Implementing Constraint Propagators, Neng-Fa Zhou, Mark Wallace, Peter J. Stuckey Jan 2006

Tr-2006013: The Dom Event And Its Use In Implementing Constraint Propagators, Neng-Fa Zhou, Mark Wallace, Peter J. Stuckey

Computer Science Technical Reports

No abstract provided.


Tr-2006014: Geometric Considerations For Distribution Of Sensors In Ad-Hoc Sensor Networks, Ted Brown, Deniz Sarioz, Amotz Bar-Noy, Tom Laporta, Dinesh Verma, Matthew Johnson, Hosam Rowaihy Jan 2006

Tr-2006014: Geometric Considerations For Distribution Of Sensors In Ad-Hoc Sensor Networks, Ted Brown, Deniz Sarioz, Amotz Bar-Noy, Tom Laporta, Dinesh Verma, Matthew Johnson, Hosam Rowaihy

Computer Science Technical Reports

No abstract provided.


Typography Behind The Arabetic Calligraphy Veil, Saad D. Abulhab Jan 2006

Typography Behind The Arabetic Calligraphy Veil, Saad D. Abulhab

Publications and Research

In the change from scriptural writing systems to textual mechanical systems and most recently to digital, computer generated text, some languages and their typographic representations have suffered. One such language, along with its visible language representation, that has not made a smooth transition is Arabic. The author argues that misinterpreting language tradition prevents what he calls Arabetic typography from embracing an appropriate technological adaptation. Putting forth an evolutionary argument, he critiques the notion that calligraphic styles must prevail and that legibility and readability of Arabic characters is objective. He further states that the resulting typefaces when abandoning the so called …


The History Of Computer Games, Jill Cirasella, Danny Kopec Jan 2006

The History Of Computer Games, Jill Cirasella, Danny Kopec

Publications and Research

This handout presents milestones in the history of computer backgammon, computer bridge, computer checkers, computer chess, computer Go, computer Othello, and computer poker.


Classical And Quantum Algorithms For Finding Cycles, Jill Cirasella Jan 2006

Classical And Quantum Algorithms For Finding Cycles, Jill Cirasella

Publications and Research

Quantum computing—so weird, so wonderful—inspires much speculation about the line between the possible and the impossible. (Of course, there is still unclarity about how “impossible” intractable problems are and about how “possible” quantum computers are.) This thesis takes a slightly different tack: instead of focusing on how to make the impossible possible, it focuses on how to make the possible easier.

More specifically, this paper discusses quantum algorithms for finding cycles in graphs, a problem for which polynomial-time classical algorithms already exist. It explains and compares the classical and quantum algorithms, and it introduces a few new algorithms and observations. …


Intersecting Circles And Their Inner Tangent Circle, Max Tran Jan 2006

Intersecting Circles And Their Inner Tangent Circle, Max Tran

Publications and Research

We derive the general equation for the radius of the inner tangent circle that is associated with three pairwise intersecting circles. We then look at three special cases of the equation.


Infinitely Often Dense Bases And Geometric Structure Of Sumsets, Jaewoo Lee Jan 2006

Infinitely Often Dense Bases And Geometric Structure Of Sumsets, Jaewoo Lee

Dissertations, Theses, and Capstone Projects

We'll discuss two problems related to sumsets.

Nathanson constructed bases of integers with prescribed representation functions, then asked how dense bases for integers can be in such cases. Let A(-x, x) be the number of elements of A whose absolute value is less than or equal to x, then it's easy to see that A(-x, x) << x1/2 if its representation function is bounded, giving us a general upper bound. Chen constructed unique representation bases for integers with A(-x, x) ≥ x1/2-epsilon infinitely often. In the first chapter, we'll construct bases for integers with a prescribed representation function with A(-x, x) > x1/2/&phis;(x) infinitely often where &phis;(x) is any nonnegative real-valued function which tends to infinity.

In the second chapter, we'll see how sumsets appear geometrically. Assume A is a finite set of lattice points and h*D=h˙x:x∈conv A is a full dimensional polytope. Then we'll see …


Countable Short Recursively Saturated Models Of Arithmetic, Erez Shochat Jan 2006

Countable Short Recursively Saturated Models Of Arithmetic, Erez Shochat

Dissertations, Theses, and Capstone Projects

Short recursively saturated models of arithmetic are exactly the elementary initial segments of recursively saturated models of arithmetic. Since any countable recursively saturated model of arithmetic has continuum many elementary initial segments which are already recursively saturated, we turn our attention to the (countably many) initial segments which are not recursively saturated. We first look at properties of countable short recursively saturated models of arithmetic and show that although these models cannot be cofinally resplendent (an expandability property slightly weaker than resplendency), these models have non-definable expansions which are still short recursively saturated.


Modeling And Measuring The Nocturnal Drainage Flow In A High-Elevation, Subalpine Forest With Complex Terrain, Chuixiang Yi, Russell K. Monson, Zhiqiang Zhai, Dean E. Anderson, Brian Lamb, Gene Allwine, Andrew A. Turnipseed, Sean P. Burns Nov 2005

Modeling And Measuring The Nocturnal Drainage Flow In A High-Elevation, Subalpine Forest With Complex Terrain, Chuixiang Yi, Russell K. Monson, Zhiqiang Zhai, Dean E. Anderson, Brian Lamb, Gene Allwine, Andrew A. Turnipseed, Sean P. Burns

Publications and Research

The nocturnal drainage flow of air causes significant uncertainty in ecosystem CO2, H2O, and energy budgets determined with the eddy covariance measurement approach. In this study, we examined the magnitude, nature, and dynamics of the nocturnal drainage flow in a subalpine forest ecosystem with complex terrain. We used an experimental approach involving four towers, each with vertical profiling of wind speed to measure the magnitude of drainage flows and dynamics in their occurrence. We developed an analytical drainage flow model, constrained with measurements of canopy structure and SF6 diffusion, to help us interpret the tower …


Tunnel Geology As Seen By Geologists: Manhattan, New York City, Nazrul I. Khandaker, Stanley Schleifer, Masud Ahmed, Alan R. Slaughter, Belal A. Sayeed, Dorean J. Flores, Mario Jo-Ramirez Oct 2005

Tunnel Geology As Seen By Geologists: Manhattan, New York City, Nazrul I. Khandaker, Stanley Schleifer, Masud Ahmed, Alan R. Slaughter, Belal A. Sayeed, Dorean J. Flores, Mario Jo-Ramirez

Publications and Research

Current exploratory boring operations in and around Manhattan, New York City are providing geologists and geotechnical engineers with a plethora of new and interesting geological information, which has not been previously reported. The rocks encountered, mostly medium to high-grade metamorphic rocks, with both mafic and felsic intrusives, are highly variable in competency and mechanical durability. One of the most frequently encountered rock types is a garnetiferous-muscovite-biotite schist which grades into schistose gneiss and displays a wide variety of structural, compositional, and textural attributes. Metamorphic minerals showing the variable degree of metamorphism include graphite, talc, garnet, kyanite, tourmaline, emory, and occasionally …


A Handheld Polarimeter For Aerosol Remote Sensing, James W. Frost, Fouad Nasraddine, J. Rodriguez, I. Andino, Brian Cairns Sep 2005

A Handheld Polarimeter For Aerosol Remote Sensing, James W. Frost, Fouad Nasraddine, J. Rodriguez, I. Andino, Brian Cairns

Publications and Research

In this paper we show how measurements made by a simple handheld polarimeter in conjunction with automated sunsky radiometers can be used to effectively constrain the real part of the complex refractive index of aerosols. We find that even measurements over a limited angular range near 90° scattering angle are sufficient for this purpose. We also note that because of the effect of surface reflectance on the observed degree of linear polarization (DOLP) it is sensible to select spectral bands for these measurements for which the surface is relatively dark and homogeneous (i.e. wavelengths shorter than 700 nm are to …


Tr-2005002: The Basic Intuitionistic Logic Of Proofs, Sergei Artemov, Rosalie Iemhoff Jan 2005

Tr-2005002: The Basic Intuitionistic Logic Of Proofs, Sergei Artemov, Rosalie Iemhoff

Computer Science Technical Reports

No abstract provided.


Tr-2005003: Making Knowledge Explicit: How Hard It Is, Vladimir Brezhnev, Roman Kuznets Jan 2005

Tr-2005003: Making Knowledge Explicit: How Hard It Is, Vladimir Brezhnev, Roman Kuznets

Computer Science Technical Reports

No abstract provided.


Tr-2005004: Basic Systems Of Epistemic Logic With Justification, Sergei Artemov, Elena Nogina Jan 2005

Tr-2005004: Basic Systems Of Epistemic Logic With Justification, Sergei Artemov, Elena Nogina

Computer Science Technical Reports

No abstract provided.


Tr-2005005: Geometric Interpretation And Spherical Property Of The 2-D Poisson Kernel, Sergei Artamoshin Jan 2005

Tr-2005005: Geometric Interpretation And Spherical Property Of The 2-D Poisson Kernel, Sergei Artamoshin

Computer Science Technical Reports

No abstract provided.


Tr-2005009: Additive Preconditioning In Matrix Computations, Victor Y. Pan, Brian Murphy, Rhys Eric Rosholt Jan 2005

Tr-2005009: Additive Preconditioning In Matrix Computations, Victor Y. Pan, Brian Murphy, Rhys Eric Rosholt

Computer Science Technical Reports

No abstract provided.


Tr-2005012: Propositional Games With Explicit Strategies, Bryan Renne Jan 2005

Tr-2005012: Propositional Games With Explicit Strategies, Bryan Renne

Computer Science Technical Reports

No abstract provided.