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2009

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Articles 5311 - 5340 of 7615

Full-Text Articles in Physical Sciences and Mathematics

Comments On "Getting Scarred And Winning Lotteries: Effects Of Exemplar Cuing And Statistical Format On Imagining Low-Probability Events," By Newell, Mitchell, And Hayes (2008), Jonathan Koehler, Laura Macchi Jan 2009

Comments On "Getting Scarred And Winning Lotteries: Effects Of Exemplar Cuing And Statistical Format On Imagining Low-Probability Events," By Newell, Mitchell, And Hayes (2008), Jonathan Koehler, Laura Macchi

Faculty Working Papers

Newell, Mitchell, and Hayes (NMH) conduct three experiments designed to test whether exemplar cuing (EC) theory or a statistical format theory provides a more accurate account for how people make judgments about low-probability events. They report finding support for the statistical format theory and little or no support for EC. However, NMH misstate the requirements for the production of exemplars in EC theory. As a result, they confuse non-exemplar conditions with exemplar conditions in their experiments, and find results that are virtually irrelevant to EC theory.


Minimotif Miner 2nd Release: A Database And Web System For Motif Search, Sanguthevar Rajasekaran, Sudha Balla, Patrick R. Gradie, Michael R. Gryk, Krishna Kadaveru, Vamsi Kundeti, Mark W. Maciejewski, Tian Mi, Nicholas Rubino, Jay Vyas, Martin R. Schiller Jan 2009

Minimotif Miner 2nd Release: A Database And Web System For Motif Search, Sanguthevar Rajasekaran, Sudha Balla, Patrick R. Gradie, Michael R. Gryk, Krishna Kadaveru, Vamsi Kundeti, Mark W. Maciejewski, Tian Mi, Nicholas Rubino, Jay Vyas, Martin R. Schiller

Life Sciences Faculty Research

Minimotif Miner (MnM) consists of a minimotif database and a web-based application that enables prediction of motif-based functions in user-supplied protein queries. We have revised MnM by expanding the database more than 10-fold to approximately 5000 motifs and standardized the motif function definitions. The web-application user interface has been redeveloped with new features including improved navigation, screencast-driven help, support for alias names and expanded SNP analysis. A sample analysis of prion shows how MnM 2 can be used.


Variability In Population Abundance Is Associated With Thresholds Between Scaling Regimes, Donald Wardwell, Craig R. Allen Jan 2009

Variability In Population Abundance Is Associated With Thresholds Between Scaling Regimes, Donald Wardwell, Craig R. Allen

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Discontinuous structure in landscapes may result in discontinuous, aggregated species bodymass patterns, reflecting the scales of structure available to animal communities within a landscape. The edges of these body-mass aggregations reflect transitions between available scales of landscape structure. Such transitions, or scale breaks, are theoretically associated with increased biological variability. We hypothesized that variability in population abundance is greater in animal species near the edge of bodymass aggregations than it is in species that are situated in the interior of body-mass aggregations. We tested this hypothesis by examining both temporal and spatial variability in the abundance of species in the …


A Neotropical Migrant Bird’S Dilemma— Where To Stop For A Good Meal, Joseph J. Fontaine, Charles Van Riper Iii Jan 2009

A Neotropical Migrant Bird’S Dilemma— Where To Stop For A Good Meal, Joseph J. Fontaine, Charles Van Riper Iii

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

To learn how migrating birds determine where to stop and find food, scientists from the U.S. Geological Survey, Northern Arizona University, and The University of Arizona studied the behavior of 28 species of neotropical migrant songbirds—warblers, flycatchers, tanagers, and vireos—along the lower Colorado River from 2001 to 2004. They found that, like interstate travelers greeted by restaurant billboards, songbirds flying over Cibola National Wildlife Refuge, Arizona, relied on the flowering of honey mesquite (Prosopis glandulosa) to detect the availability of insects that they prey on. Understanding where and why migrant birds stop will help land managers better protect …


Stomach Capacities Of Six Freshwater Fishes, Nathan J.C. Gosch, Kevin L. Pope, Paul H. Michaletz Jan 2009

Stomach Capacities Of Six Freshwater Fishes, Nathan J.C. Gosch, Kevin L. Pope, Paul H. Michaletz

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

We investigated the relationship between stomach capacity and total body length in bluegill (Lepomis macrocirirus), spotted bass (Microplerus punctulatus), white crappie (Pomoxis annularis), black crappie (Pomoxis nigromoculatus), channel catfish (Ictalurus punctatus) , and white bass (Morone chrysops). The rate of change in stomach capacity for a given change in fish length was greatest for spoiled bass and channel catfish, which may indicate greater ontogenetic shifts in feeding strategies. Fish with larger stomach capacities should have more plastic diets because they are capable of consuming a wider range of …


Seasonal Patterns Of Song Structure Variation In A Suboscine Passerine, Bruce A. Robertson, Joseph J. Fontaine, Elizabeth Loomis Jan 2009

Seasonal Patterns Of Song Structure Variation In A Suboscine Passerine, Bruce A. Robertson, Joseph J. Fontaine, Elizabeth Loomis

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Studies of song and its function in suboscine passerines are rare. We examined spatial and temporal variation in song structure in a wild population of Olive-sided Flycatchers (Contopus cooperi) and tested among hypotheses explaining this variation. Repeatable variation in song type was observed both within and among individuals. More than 10% of territorial males expressed atypical song types, i.e., permutations of sequential missing and repeated elements of the typical adult song. Atypical songs were predominantly expressed by unpaired males independent of habitat type. A small fraction of males sang atypical song through the middle of the breeding season, …


Droughtscape- Winter 2009, Kelly Smith Jan 2009

Droughtscape- Winter 2009, Kelly Smith

Droughtscape, Quarterly Newsletter of NDMC, 2007-

Bastrop TX: Feb. 12 Central CA: Feb. 24, 26

La Niña May Keep West and Gulf Coast Dry

Big Canoes to Launch

2008 in Review

U.S. Feels Drought Impacts in 2008

NDMC Welcomes Widhalm, Sakamoto

Climate Modelers at Workshop Look to Sea Surface Temperatures for Drought Prediction


Exploring Temporal And Rate Limits Of Laser-Induced Electron Emission, Shawn A. Hilbert, A. Neukirch, Cornelis J. Uiterwaal, Herman Batelaan Jan 2009

Exploring Temporal And Rate Limits Of Laser-Induced Electron Emission, Shawn A. Hilbert, A. Neukirch, Cornelis J. Uiterwaal, Herman Batelaan

C.J.G.J. Uiterwaal Publications

To achieve high temporal resolution for ultrafast electron diffraction, Zewail (Proc. Natl Acad. Sci. USA 102, 7069 (2005)) has proposed to use high repetition rate, ultrafast electron sources. Such electron sources emitting one electron per pulse eliminate Coulomb broadening. High repetition rates are necessary to achieve reasonable data acquisition times. We report laser-induced emission from a nanometre-sized tip at one electron per pulse with a 1 kHz repetition rate in the femtosecond regime. This source, combined with 1 MHz repetition rate lasers that are becoming available, will be a primary candidate for next generation ultrafast, high-coherence electron diffraction experiments. …


Absence Of Spin Liquid Behavior In Nd3ga5sio14 Using Magneto-Optical Spectroscopy, X. S. Xu, T. V. Brinzari, S. Mcgill, H. D. Zhou, C. R. Wiebe, J. L. Musfeldt Jan 2009

Absence Of Spin Liquid Behavior In Nd3ga5sio14 Using Magneto-Optical Spectroscopy, X. S. Xu, T. V. Brinzari, S. Mcgill, H. D. Zhou, C. R. Wiebe, J. L. Musfeldt

Xiaoshan Xu Papers

We measured the low-lying crystal field levels of Nd3+ in Nd3Ga5SiO14 via magneto-optical spectroscopy and employed the extracted energies, magnetic moments, and symmetries to analyze the magnetic properties and test the spin liquid candidacy of this material. The exchange interaction is surprisingly small, a discovery that places severe constraints on models used to describe the ground state of this system. Further, it demonstrates the value of local-probe photophysical techniques for rare-earthcontaining materials where bulk property measurements can be skewed by low-lying electronic structure.


Magnon Sidebands And Spin-Charge Coupling In Bismuth Ferrite Probed By Nonlinear Optical Spectroscopy, M. O. Ramirez, A. Kumar, S. A. Denev, N. J. Podraza, X. S. Xu, R. C. Rai, Y. H. Chu, J. Seidel, L. W. Martin, S. -Y. Yang, E. Saiz, J. F. Ihlefeld, S. Lee, J. Klug, S. W. Cheong, M. J. Bedzyk, O. Auciello, D. G. Schlom, R. Ramesh, J. Orenstein, J. L. Musfeldt, V. Gopalan Jan 2009

Magnon Sidebands And Spin-Charge Coupling In Bismuth Ferrite Probed By Nonlinear Optical Spectroscopy, M. O. Ramirez, A. Kumar, S. A. Denev, N. J. Podraza, X. S. Xu, R. C. Rai, Y. H. Chu, J. Seidel, L. W. Martin, S. -Y. Yang, E. Saiz, J. F. Ihlefeld, S. Lee, J. Klug, S. W. Cheong, M. J. Bedzyk, O. Auciello, D. G. Schlom, R. Ramesh, J. Orenstein, J. L. Musfeldt, V. Gopalan

Xiaoshan Xu Papers

The interplay between spin waves (magnons) and electronic structure in materials leads to the creation of additional bands associated with electronic energy levels which are called magnon sidebands. The large difference in the energy scales between magnons (meV) and electronic levels (eV) makes this direct interaction weak and hence makes magnon sidebands difficult to probe. Linear light absorption and scattering techniques at low temperatures are traditionally used to probe these sidebands. Here we show that optical secondharmonic generation, as the lowest-order nonlinear process, can successfully probe the magnon sidebands at room temperature and up to 723 K in bismuth ferrite, …


Magnetic Correlations In Nanocomposite Fept:Au And Fept:C Films, Thomas A. George, Ralph Skomski, David J. Sellmyer Jan 2009

Magnetic Correlations In Nanocomposite Fept:Au And Fept:C Films, Thomas A. George, Ralph Skomski, David J. Sellmyer

Ralph Skomski Publications

The nanostructure and magnetism of L10-ordered FePt crystallites in matrices of Au and C are investigated as a function of the Au and C contents. Emphasis is on the relation between hysteresis-loop shape, magnetic correlation length, and structural disorder, as relevant to magnetic recording media. The highly (001) textured thin films are produced by annealing [Fe&#;&#;Pt&#;X]n multilayers. The coercivity and the hysteresis-loop slope at coercivity increase and decrease, respectively, with increasing volume fraction of the matrix. The magnetic force microscopy images show that the slope decrease is accompanied by a reduction in the magnetic correlation length. These …


2009 Nebraska Game And Parks Commission Broodstock Collection, Kirk Steffensen, Jeff Koch Jan 2009

2009 Nebraska Game And Parks Commission Broodstock Collection, Kirk Steffensen, Jeff Koch

Nebraska Game and Parks Commission: Publications

The Nebraska Game and Parks Commission (NGPC) organized the second intensive effort targeted towards sampling pallid sturgeon in reproductive condition in the upper channelized Missouri River. Volunteers were solicited from area universities, colleges, and state and federal agencies to assist Game and Parks personnel from Monday, April 6 through Saturday, April 18 (excluding Easter weekend).

Sampling crews targeted areas around the confluence of the Platte and Missouri Rivers (River Mile [RM] 595.0) to Peru, NE (RM 542.0). With the additional help from volunteers, crews were able to span a total of 43 river miles and sample 25 different river bends. …


Ferroelectricity In Ultrathin Strained Batio3 Films: Probing The Size Effect By Ultraviolet Raman Spectroscopy, Dmitri Tenne, P. Turner, J. D. Schmidt, M. Biegalski, Y. L. Li, L. Q. Chen, A. Soukiassian Jan 2009

Ferroelectricity In Ultrathin Strained Batio3 Films: Probing The Size Effect By Ultraviolet Raman Spectroscopy, Dmitri Tenne, P. Turner, J. D. Schmidt, M. Biegalski, Y. L. Li, L. Q. Chen, A. Soukiassian

Physics Faculty Publications and Presentations

We demonstrate a dramatic effect of film thickness on the ferroelectric phase transition temperature, Tc, in strained BaTiO3 films grown on SrTiO3 substrates. Using variable temperature ultraviolet Raman spectroscopy enables measuring Tc in films as thin as 1.6 nm, and film thickness variation from 1.6 to 10 nm leads to Tc tuning from 70 to about 925K. Raman data are consistent with synchrotron x-ray scattering results, which indicate the presence of of 180 domains below Tc, and thermodynamic phase-field model calculations of Tc as a function of thickness.


Development Of Measurement And Modeling Techniques To Quantify Atmospheric Deposition Of Persistent, Bioaccumulative And Toxic Chemicals In The Great Lakes, Mark D. Rowe Jan 2009

Development Of Measurement And Modeling Techniques To Quantify Atmospheric Deposition Of Persistent, Bioaccumulative And Toxic Chemicals In The Great Lakes, Mark D. Rowe

Dissertations, Master's Theses and Master's Reports - Open

Measurement and modeling techniques were developed to improve over-water gaseous air-water exchange measurements for persistent bioaccumulative and toxic chemicals (PBTs). Analytical methods were applied to atmospheric measurements of hexachlorobenzene (HCB), polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs). Additionally, the sampling and analytical methods are well suited to study semivolatile organic compounds (SOCs) in air with applications related to secondary organic aerosol formation, urban, and indoor air quality.

A novel gas-phase cleanup method is described for use with thermal desorption methods for analysis of atmospheric SOCs using multicapillary denuders. The cleanup selectively removed hydrogen-bonding chemicals from samples, including much of …


Identification Of Human Gait Using Genetic Algorithm Tuned Fuzzy Logic, Abdallah Abdel-Rahman Hassan Mahmoud Jan 2009

Identification Of Human Gait Using Genetic Algorithm Tuned Fuzzy Logic, Abdallah Abdel-Rahman Hassan Mahmoud

Open Access Theses & Dissertations

Data mining is concerned with the discovery of useful hidden information in large databases. Classification is a data mining task producing rules in which a set of attributes in data predict the value of a class attribute. Classifiers usually produce a large number of rules, most of which are not interesting to the user. Rule interestingness is a decisive factor. However, evaluating rule interestingness is challenging as it involves both objective (data-driven) and subjective (user-driven) aspects.

In this research, a fuzzy genetic algorithm is proposed to discover classification rules that are both accurate and interesting. Continuous attributes are fuzzified so …


Towards More Reliable Extrapolation Algorithms With Applications To Organic Chemistry, Jaime Nava Jan 2009

Towards More Reliable Extrapolation Algorithms With Applications To Organic Chemistry, Jaime Nava

Open Access Theses & Dissertations

One of the main objectives of science and engineering is to predict the results of different situations. For example, in Newton's mechanics, we want to predict the positions and velocities of different objects (e.g., planets) at future moments of time.

In this Thesis, as a case study, we take the problem of predicting the properties of new chemical substances. One of the main objectives of chemistry is to design new molecules (and, more generally, new chemical compounds) which are useful for various practical tasks. New substances have already resulted in new materials for buildings and for spaceships, new explosives and …


Temporomandibular Joint Loads In Subjects With And Without Disc Displacement, Laura R. Iwasaki, Michael J. Crosby, Yoly Gonzalez, Willard D. Mccall, David B. Marx, Richard Ohrbach, Jeffrey C. Nickel Jan 2009

Temporomandibular Joint Loads In Subjects With And Without Disc Displacement, Laura R. Iwasaki, Michael J. Crosby, Yoly Gonzalez, Willard D. Mccall, David B. Marx, Richard Ohrbach, Jeffrey C. Nickel

Department of Statistics: Faculty Publications

The likelihood of development of degenerative joint disease (DJD) of the temporomandibular joint (TMJ) is related to the integrity of the TMJ disc. Predilection for mechanical failure of the TMJ disc may reflect inter-individual differences in TMJ loads. Nine females and eight males in each of normal TMJ disc position and bilateral disc displacement diagnostic groups consented to participate in our study. Disc position was determined by bilateral magnetic resonance images of the joints. Three-dimensional (3D) anatomical geometry of each subject was used in a validated computer-assisted numerical model to calculate ipsilateral and contralateral TMJ loads for a range of …


Temporomandibular Joint Loads In Subjects With And Without Disc Displacement, Laura R. Iwasaki, Michael J. Crosby, Yoly Gonzalez, Willard D. Mccall, David B. Marx, Richard Ohrbach, Jeffrey C. Nickel Jan 2009

Temporomandibular Joint Loads In Subjects With And Without Disc Displacement, Laura R. Iwasaki, Michael J. Crosby, Yoly Gonzalez, Willard D. Mccall, David B. Marx, Richard Ohrbach, Jeffrey C. Nickel

Department of Statistics: Faculty Publications

The likelihood of development of degenerative joint disease (DJD) of the temporomandibular joint (TMJ) is related to the integrity of the TMJ disc. Predilection for mechanical failure of the TMJ disc may reflect inter-individual differences in TMJ loads. Nine females and eight males in each of normal TMJ disc position and bilateral disc displacement diagnostic groups consented to participate in our study. Disc position was determined by bilateral magnetic resonance images of the joints. Three-dimensional (3D) anatomical geometry of each subject was used in a validated computer-assisted numerical model to calculate ipsilateral and contralateral TMJ loads for a range of …


Conceptual Circuit Models Of Neurons, Bo Deng Jan 2009

Conceptual Circuit Models Of Neurons, Bo Deng

Department of Mathematics: Faculty Publications

A systematic circuit approach tomodel neurons with ion pump is presented here by which the voltage-gated current channels are modeled as conductors, the diffusion-induced current channels are modeled as negative resistors, and the one-way ion pumps are modeled as one-way inductors. The newly synthesized models are different from the type of models based on Hodgkin-Huxley (HH) approach which aggregates the electro, the diffusive, and the pump channels of each ion into one conductance channel. We show that our new models not only recover many known properties of the HH type models but also exhibit some new that cannot be extracted …


Applications Of Modern Classification Methods To Predict Occurrences Of Rare And Invasive Plant Species, Stacey Reynolds Jan 2009

Applications Of Modern Classification Methods To Predict Occurrences Of Rare And Invasive Plant Species, Stacey Reynolds

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Statistical classification methods are among the most widely used statistical procedures in ecology. Applications include vegetation mapping by remote sensing (Steele 2000), discrimination of subspecies using morphological measurements (Fisher 1936, 1938; Conner and Schenk 2003), and species distribution modelling (Guisan and Zimmerman 2000). Examples of the last application abound in the ecological literature and include predicting the distribution or characteristics of plant species (see, e.g., Austin et al. 1990), predicting presence and absence aquatic biota in streams (Hawkins et al. 2000), and habit at relationships of terrestrial animal species (Welch and MacMahon 2005). Over the last 20 years two mainstays …


Heritability Of Cognition Subscales In The Cache County Memory Study Cohort And Methods For Estimating Heritability, Colette Kelly Childs Jan 2009

Heritability Of Cognition Subscales In The Cache County Memory Study Cohort And Methods For Estimating Heritability, Colette Kelly Childs

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

The rapid improvement of genotyping technology holds the promise of better understanding the genetic causes of complex disease. While traits of interest often include the presence or absence of disease, there is growing interest in intermediate phenotypes (or so-called endophenotypes) that may yield more information about disease onset or course. In particular, changes over time with respect to an investigative ordinal measure often contain significant predictive power, and rate-of-change phenotypes are becoming important in their own right when studying genetic association. Initial steps in assessing the potential genetic determinants of a continuous trait often involve estimating the degree of the …


Cow Insurance Vs. Human Insurance: A Comparison Study, Corlan Fawcett Jan 2009

Cow Insurance Vs. Human Insurance: A Comparison Study, Corlan Fawcett

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

This paper will compare the premiums to insure cows and humans for n-year term, n-year endowment, and whole life insurance. It will go into more depth for whole life premium s that would be charged, such that the insurance company is 95 percent confident that they will not lose money. In particular the paper will look at how the variance affects the premiums for an insurance company insuring 100 cows.


Evaluating The Effectiveness Of A Probability Applet, Chelsa Green Tuddenham Jan 2009

Evaluating The Effectiveness Of A Probability Applet, Chelsa Green Tuddenham

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

The purpose of this project was to develop and examine a computerized interactive probability applet designed to teach basic concepts of probability. The applet design was intended to be a user-friendly way to encourage understanding of basic probability concepts such as, rules of probability, probabilities of mutually exclusive events, and the multiplication rule. Thirty participants were recruited from Utah State University and were asked to participate in the evaluation process of the probability applet. The evaluation of the probability applet consisted of three parts: First, a group of participants were video recorded and asked to voice any and all thoughts …


China And Global Climate Change : Proceedings Of The Conference Held At Lingnan University, Hong Kong, 18-19 June 2009, Paul G. Harris Jan 2009

China And Global Climate Change : Proceedings Of The Conference Held At Lingnan University, Hong Kong, 18-19 June 2009, Paul G. Harris

Centre for Asian Pacific Studies (CAPS) : Book Publications

The conference on China and Global Climate Change was held at Lingnan University, Hong Kong, from 18-19 June 2009. About 100 scholars from around the world participated in the conference. They served in various capacities, including as presenters, researchers, paper writers and/or discussants. The conference was jointly organized and sponsored by Lingnan University's Centre for Asian Pacific Studies (CAPS) and its Environmental Studies Programme (ESP). The objective of the conference was to examine the problem of how to reconcile China's growing greenhouse gas emissions with the Chinese government's unwillingness (so far) to join binding international commitments to reduce those emissions. …


Insecurity By Obscurity: A Review Of Soho Router Literature From A Network Security Perspective, Patryk Szewczyk, Craig Valli Jan 2009

Insecurity By Obscurity: A Review Of Soho Router Literature From A Network Security Perspective, Patryk Szewczyk, Craig Valli

Research outputs pre 2011

Because of prevalent threats to SoHo based ADSL Routers, many more devices are compromised. Whilst an end-user may be at fault for not applying the appropriate security mechanisms to counter these threats, vendors should equally share the blame. This paper reveals that the lack of security related content and poor overall design could impact on end-users’ interpretation and willingness to implement security controls on their ADSL router. It argues that whilst the number of threats circulating the Internet is increasing, vendors are not improving their product literature.


A Semiparametric Approach To A Nonlinear Acd Model, Pipat Wongsaart, Jiti Gao, David E. Allen Jan 2009

A Semiparametric Approach To A Nonlinear Acd Model, Pipat Wongsaart, Jiti Gao, David E. Allen

Research outputs pre 2011

We introduce in this paper a new semiparametric approach to a nonlinear ACD model, namely the Semiparametric ACD (SEMI-ACD) model. This new model is more flexible in the sense that the data are allowed to speak for themselves, without a hypothetical assumption being imposed arbitrarily on its key component. Moreover, it enables a much more thorough examination of the intertemporal importance of the conditional duration on the ACD process. Our experimental analysis suggests that the new model possesses a sound asymptotic character, while its performance is also robust across data generating processes and assumptions about the conditional distribution of the …


Electric Multipole Moments Of Some Diatomic Molecules Molecules, M. Özgür Sezer, Ayhan Özmen, Hüseyi̇n Yüksel Jan 2009

Electric Multipole Moments Of Some Diatomic Molecules Molecules, M. Özgür Sezer, Ayhan Özmen, Hüseyi̇n Yüksel

Turkish Journal of Physics

Molecular Electric Multipole Moment (MEMM) integrals have been derived for diatomic molecular systems, and then some lower multipole moments as dipole moments and quadrupole moments have been calculated for some diatomic molecules. The calculations have been performed by using our analytical formula over Slater-Type orbitals (STOs) with Cade and Huo's basis sets and the GAMESS program package working with Gaussian-Type basis sets (GTOs). The expressions which involve factorials are given in terms of binomial coefficients in order to speed up calculations. The results have been obtained in agreement with data found in the literature.


Kantowski-Sachs Viscous Fluid Cosmological Model With A Varying \Lambda, Sharad Kandalkar, Pramod Khade, Sunita Gawande Jan 2009

Kantowski-Sachs Viscous Fluid Cosmological Model With A Varying \Lambda, Sharad Kandalkar, Pramod Khade, Sunita Gawande

Turkish Journal of Physics

We study the Kantowski-Sachs cosmological model filled with viscous fluid in the presence of cosmological term \Lambda. To get a deterministic solution, a condition between metric potentials is used. The viscous coefficient of bulk viscous fluid is assumed to be a power function of mass density, whereas coefficient of shear viscosity is considered proportional to scale of expansion in the model. It is found that the cosmological constant \Lambda is positive and is a decreasing function of time, which is supported by results from recent supernova observations. Some physical and geometrical properties of the models are also discussed.


Exact Peaked Wave Solution Of The Osmosis K(2,2) Equation, Xijun Deng, Libo Han Jan 2009

Exact Peaked Wave Solution Of The Osmosis K(2,2) Equation, Xijun Deng, Libo Han

Turkish Journal of Physics

By using the first-integral method, an exact peaked wave solution to the K(2,2) equation with osmosis dispersion has been obtained directly. The obtained solution agrees well with the previously known solution in the literature. The first integral method is easier and quicker than other traditional techniques. It is shown that the first integral method is a standard and direct method, which may allow us to solve other more complicated solitary wave problems.


Dielectric Properties Of Liquid Systems: The Ideal Complex Permittivity In Liquid Mixtures, Adrian H. Buep Jan 2009

Dielectric Properties Of Liquid Systems: The Ideal Complex Permittivity In Liquid Mixtures, Adrian H. Buep

Turkish Journal of Physics

A general definition for ideal complex permittivity in a liquid mixture was reached by considering a thermodynamically ideal mixture under the effect of an applied harmonic electric field. The resulting definition is independent of any particular dielectric model, as well as the polarity of the components.