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2006

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Pendant ^{13}C Nmr Spectroscopy Applied To Ch_N Groups, Azmi̇ Gençten, İrfan Şaka, Sedat Gümüş Jan 2006

Pendant ^{13}C Nmr Spectroscopy Applied To Ch_N Groups, Azmi̇ Gençten, İrfan Şaka, Sedat Gümüş

Turkish Journal of Physics

Polarization enhancement nurtured during attached nucleus testing (PENDANT) NMR spectroscopy gives signals of quaternary carbon atoms in addition to signals indicative of CH, CH_2 and CH_3 groups. In this study, using product operator theory, analytical description of PENDANT NMR spectroscopy for CH_n (IS_n, I = 1/2, S = 1/2, n = 0, 1, 2, 3) spin systems are presented. Simulation and experimental results of PENDANT NMR spectroscopy are also presented. Theoretical results are found to be in exact agreement with the simulation results and in good agreement with the experimental ones.


Ramifications Of Lineland, Daniel Grumiller, Rene Meyer Jan 2006

Ramifications Of Lineland, Daniel Grumiller, Rene Meyer

Turkish Journal of Physics

A non-technical overview on gravity in two dimensions is provided. Applications discussed in this work comprise 2D type 0A/0B string theory, Black Hole evaporation/thermodynamics, toy models for quantum gravity, for numerical General Relativity in the context of critical collapse and for solid state analogues of Black Holes. Mathematical relations to integrable models, non-linear gauge theories, Poisson-sigma models, KdV surfaces and non-commutative geometry are presented.


Equivariant Localization For Susy Quantum Mechanics, Levent Akant Jan 2006

Equivariant Localization For Susy Quantum Mechanics, Levent Akant

Turkish Journal of Physics

We apply equivariant localization to supersymmetric quantum mechanics and show that the partition function localizes on the instantons of the theory. Our construction of equivariant cohomology for SUSY quantum mechanics is different than the ones that already exist in the literature. A hidden bosonic symmetry is made explicit and the supersymmetry is extended. New bosonic symmetry is the square of the new fermionic symmetry. The D term is now the parameter of the bosonic symmetry. This construction provides us with an equivariant complex together with a Cartan differential and makes the use of localization principle possible.


Plane Symmetric Solutions Of Gravitational Field Equations In Five Dimensions, A. N. Aliev, Hakan Cebeci̇, Teki̇n Dereli̇ Jan 2006

Plane Symmetric Solutions Of Gravitational Field Equations In Five Dimensions, A. N. Aliev, Hakan Cebeci̇, Teki̇n Dereli̇

Turkish Journal of Physics

We present the effective field equations obtained from a generalized gravity action with Euler-Poincaré term and a cosmological constant in a D dimensional bulk space-time. A class of plane-symmetric solutions that describe a 3-brane world embedded in a D=5 dimensional bulk space-time are given.


Charges In Ads Spacetimes, İbrahi̇m Güllü, Bayram Teki̇n Jan 2006

Charges In Ads Spacetimes, İbrahi̇m Güllü, Bayram Teki̇n

Turkish Journal of Physics

We give a review of our recent work on conserved charges in cosmological spacetimes. We compute the mass and the angular momenta of various solutions in D dimensions. This is an extended version of a talk given by B. Tekin. The original material can be found in the related papers in our references.


Coset Algebras Of The Maxwell-Einstein Supergravities, Nejat Tevfi̇k Yilmaz Jan 2006

Coset Algebras Of The Maxwell-Einstein Supergravities, Nejat Tevfi̇k Yilmaz

Turkish Journal of Physics

The general structure of the scalar cosets of the Maxwell-Einstein supergravities is given. Following an introduction of the non-linear coset formalism of the supergravity theories a comparison of the coset algebras of the Maxwell-Einstein supergravities in various dimensions is discussed.


What's The Story With Storyline Patents-An Argument Against The Allowance Of Proposed Storyline Patents And For The Rejection Of Currently Pending Storyline Patent Applications, Ben Manevitz Jan 2006

What's The Story With Storyline Patents-An Argument Against The Allowance Of Proposed Storyline Patents And For The Rejection Of Currently Pending Storyline Patent Applications, Ben Manevitz

Cardozo Arts & Entertainment Law Journal

No abstract provided.


Pulsar Studies Of Tiny-Scale Structure In The Neutral Ism, Joel M. Weisberg, S. Stanimirovi´C Jan 2006

Pulsar Studies Of Tiny-Scale Structure In The Neutral Ism, Joel M. Weisberg, S. Stanimirovi´C

Physics and Astronomy Faculty Work

We describe the use of pulsars to study small-scale neutral structure in the interstellar medium (ISM). Because pulsars are high velocity objects, the pulsarEarth line of sight sweeps rapidly across the ISM. Multiepoch measurements of pulsar interstellar spectral line spectra therefore probe ISM structures on AU scales. We review pulsar measurements of small scale structure in HI and OH and compare these results with those obtained through other techniques.


Lady Griz Volleyball Media Guide, 2006, University Of Montana—Missoula. Athletics Department Jan 2006

Lady Griz Volleyball Media Guide, 2006, University Of Montana—Missoula. Athletics Department

Lady Griz Volleyball Media Guides, 1979-2008

Media guide created about the Lady Griz volleyball team.


Strafford County 2005 Annual Report Of The Commissioners, Treasurer, Other County Officers And The Strafford County Delegation Strafford County, New Hampshire For The Year Ending December 31, 2005., Stafford County Representatives Jan 2006

Strafford County 2005 Annual Report Of The Commissioners, Treasurer, Other County Officers And The Strafford County Delegation Strafford County, New Hampshire For The Year Ending December 31, 2005., Stafford County Representatives

Strafford County, NH Annual Reports

This is an annual report containing vital statistics for a county in the state of New Hampshire.


Thirwall Project, Anwar Shaikh Phd Jan 2006

Thirwall Project, Anwar Shaikh Phd

Archives of Anwar Shaikh

This collection includes.

• Abu-Ismail, K. (2006, April). Exports and imports growth rates (1960–1999). Unpublished document.

• Puty, C. (2002, January 31). Email to Anwar Shaikh: Fwd: R: Cointegration (Discussion of cointegration and dummy variables with Riccardo Fiorito). Unpublished email correspondence.

• Contri, A., & Puty, C. (2001, August 13). Explaining Thirlwall’s law. Unpublished document.

• Handwritten notes on Thirwall’s law. (n.d.). Unpublished handwritten notes [Manuscript]. (A. Shaikh, PhD, author).

• Handwritten notes titled “structural breaks and regressions.” (2000, November 11). Unpublished handwritten notes [Manuscript]. (A. Shaikh, PhD, author).

• File hypothetical.wf1: Generating artificial data for terms …


Why Is The Number Of Dna Bases 4?, Bo Deng Jan 2006

Why Is The Number Of Dna Bases 4?, Bo Deng

Department of Mathematics: Faculty Publications

In this paper we construct a mathematical model for DNA replication based on Shannon’s mathematical theory for communication. We treatDNAreplication as a communication channel. We show that the mean replication rate is maximal with four nucleotide bases under the primary assumption that the pairing time of the G–C bases is between 1.65 and 3 times the pairing time of the A–T bases.


Long-Term Reduction Of Trypanosoma Cruzi Infection In Sylvatic Mammals Following Deforestation And Sustained Vector Surveillance In Northwestern Argentina, L. A. Ceballos, M. V. Cardinal, G. M. Vazquez-Prokopec, M. A. Lauricella, M. M. Orozco, M. Roberto Cortinas, A. G. Schijman, M. J. Levin, Uriel Kitron, R. E. Gürtlera Jan 2006

Long-Term Reduction Of Trypanosoma Cruzi Infection In Sylvatic Mammals Following Deforestation And Sustained Vector Surveillance In Northwestern Argentina, L. A. Ceballos, M. V. Cardinal, G. M. Vazquez-Prokopec, M. A. Lauricella, M. M. Orozco, M. Roberto Cortinas, A. G. Schijman, M. J. Levin, Uriel Kitron, R. E. Gürtlera

Department of Entomology: Faculty Publications

Long-term variations in the dynamics and intensity of sylvatic transmission of Trypanosoma cruzi were investigated around eight rural villages in the semiarid Argentine Chaco in 2002–2004 and compared to data collected locally in 1984–1991. Of 501 wild mammals from 13 identified species examined by xenodiagnosis, only 3 (7.9%) of 38 Didelphis albiventris opossums and 1 (1.1%) of 91 Conepatus chinga skunks were infected by T. cruzi. The period prevalence in opossums was fourfold lower in 2002–2004 than in 1984–1991 (32–36%). The infection prevalence of skunks also decreased five-fold from 4.1–5.6% in 1984–1991 to 1.1% in 2002–2004. Infection in opossums increased …


Effects Of Temperature On Development Of Phormia Regina (Diptera: Calliphoridae) And Use Of Developmental Data In Determining Time Intervals In Forensic Entomology, P. D. Nabity, Leon G. Higley, Tiffany M. Heng-Moss Jan 2006

Effects Of Temperature On Development Of Phormia Regina (Diptera: Calliphoridae) And Use Of Developmental Data In Determining Time Intervals In Forensic Entomology, P. D. Nabity, Leon G. Higley, Tiffany M. Heng-Moss

Department of Entomology: Faculty Publications

Precise developmental data for forensic indicator blow fly species are essential for accuracy in the estimate of the post-mortem interval (PMI). Why, then, does the determination of the PMI result in conflicting time frames when published conspecific developmental data are used? To answer this question, we conducted constant temperature trials between the developmental minimum temperature and upper threshold temperatures (8-32 degrees C) on the forensically important blow fly species Phormia regina (Meigen) (Diptera: Calliphoridae). Flies were reared using two designs to quantify sources of variation. We measured rearing container temperatures and internal growth chamber temperatures by using thermocouples to accurately …


Automated Generation Of Context-Aware Tests, Zhimin Wang, Sebastian Elbaum, David Rosenblum Jan 2006

Automated Generation Of Context-Aware Tests, Zhimin Wang, Sebastian Elbaum, David Rosenblum

School of Computing: Technical Reports

The incorporation of context-awareness capabilities into pervasive applications allows them to leverage contextual information to provide additional services while maintaining an acceptable quality of service. These added capabilities, however, introduce a distinct input space that can affect the behavior of these applications at any point during their execution, making their validation quite challenging. In this paper, we introduce an approach to improve the test suite of a context-aware application by identifying context-aware program points where context changes may affect the application’s behavior, and by systematically manipulating the context data fed into the application to increase its exposure to potentially valuable …


A New Cryptographic Scheme For Securing Dynamic Conferences In Data Networks, Sarang Deshpande, Ajay Todimala, Ravi K Balachandran, Byrav Ramamurthy, Xukai Zou, N. V. Vinodchandran Jan 2006

A New Cryptographic Scheme For Securing Dynamic Conferences In Data Networks, Sarang Deshpande, Ajay Todimala, Ravi K Balachandran, Byrav Ramamurthy, Xukai Zou, N. V. Vinodchandran

School of Computing: Conference and Workshop Papers

Dynamic conferencing refers to a scenario wherein any subset of users in a universe of users form a conference for sharing confidential information among themselves. The key distribution (KD) problem in dynamic conferencing is to compute a shared secret key for such a dynamically formed conference. In literature, the KD schemes for dynamic conferencing either are computationally unscalable or require communication among users, which is undesirable. The extended symmetric polynomial based dynamic conferencing scheme (ESPDCS) is one such KD scheme which has a high computational complexity that is universe size dependent. In this paper we present an enhancement to the …


Router And Firewall Redundancy With Openbsd And Carp, Garhan Attebury, Byrav Ramamurthy Jan 2006

Router And Firewall Redundancy With Openbsd And Carp, Garhan Attebury, Byrav Ramamurthy

School of Computing: Conference and Workshop Papers

As more reliance is placed on computing and networking systems, the need for redundancy increases. The Common Address Redundancy Protocol (CARP) protocol and OpenBSD’s pfsync utility provide a means by which to implement redundant routers and firewalls. This paper details how CARP and pfsync work together to provide this redundancy and explores the performance one can expect from the open source solutions. Two experiments were run: one showing the relationship between firewall state creation and state synchronization traffic and the other showing how TCP sessions are transparently maintained in the event of a router failure. Discussion of these simulations along …


Autonomous Clustering-Based Heterogeneous Waveband Switching In Wdm Networks, Mengke Li, Byrav Ramamurthy Jan 2006

Autonomous Clustering-Based Heterogeneous Waveband Switching In Wdm Networks, Mengke Li, Byrav Ramamurthy

School of Computing: Conference and Workshop Papers

Employing waveband switching (WBS) in WDM networks can reduce the network operational cost and the call blocking probability. However, upgrading the existing optical switching architecture requires time and money. It is expected that a heterogeneous waveband switching (HeteroWBS) architecture would be desirable, where some nodes can support WBS functions and some cannot. We study the performance of HeteroWBS networks in terms of call blocking probability and cost savings under dynamic traffic requests. We propose an autonomous clustering-based HeteroWBS (AS-HeteroWBS) architecture to clusters the network into multiple autonomous systems (ASs). An AS may contain some specific nodes that provide WBS functions …


Integrated Intermediate Waveband And Wavelength Switching For Optical Wdm Mesh Networks, Mengke Li, Byrav Ramamurthy Jan 2006

Integrated Intermediate Waveband And Wavelength Switching For Optical Wdm Mesh Networks, Mengke Li, Byrav Ramamurthy

School of Computing: Conference and Workshop Papers

As wavelength-division multiplexing (WDM) evolves towards practical applications in optical transport networks, waveband switching (WBS) has been introduced to cut down the operational costs and to reduce the complexities and sizes of network components, e.g., optical cross-connects (OXCs). This paper considers the routing, wavelength assignment and waveband assignment (RWWBA) problem in a WDM network supporting mixed waveband and wavelength switching. First, the techniques supporting waveband switching are studied, where a node architecture enabling mixed waveband and wavelength switching is proposed. Second, to solve the RWWBA problem with reduced switching costs and improved network throughput, the cost savings and call blocking …


Dynamic Lightpath Scheduling In Next-Generation Wdm Optical Networks, Lu Shen, Ajay Todimala, Byrav Ramamurthy, Xi Yang Jan 2006

Dynamic Lightpath Scheduling In Next-Generation Wdm Optical Networks, Lu Shen, Ajay Todimala, Byrav Ramamurthy, Xi Yang

School of Computing: Conference and Workshop Papers

Lightpath scheduling is an important capability in next-generation wavelength-division multiplexing (WDM) optical networks to reserve resources in advance for a specified time period while provisioning end-to-end lightpaths. In this study, we propose an approach to support dynamic lightpath scheduling in such networks. To minimize blocking probability in a network that accommodates dynamic scheduled lightpath demands (DSLDs), resource allocation should be optimized in a dynamic manner. However, for the network users who desire deterministic services, resources must be reserved in advance and guaranteed for future use. These two objectives may be mutually incompatible. Therefore, we propose a two-phase dynamic lightpath scheduling …


A Survey Of Security Issues In Wireless Sensor Networks, Yong Wang, Garhan Attebury, Byrav Ramamurthy Jan 2006

A Survey Of Security Issues In Wireless Sensor Networks, Yong Wang, Garhan Attebury, Byrav Ramamurthy

School of Computing: Faculty Publications

Wireless Sensor Networks (WSNs) are used in many applications in military, ecological, and health-related areas. These applications often include the monitoring of sensitive information such as enemy movement on the battlefield or the location of personnel in a building. Security is therefore important in WSNs. However, WSNs suffer from many constraints, including low computation capability, small memory, limited energy resources, susceptibility to physical capture, and the use of insecure wireless communication channels. These constraints make security in WSNs a challenge. In this article we present a survey of security issues in WSNs. First we outline the constraints, security requirements, and …


The Performance Of Elliptic Curve Based Group Diffie-Hellman Protocols For Secure Group Communication Over Ad Hoc Networks, Yong Wang, Byrav Ramamurthy, Xukai Zou Jan 2006

The Performance Of Elliptic Curve Based Group Diffie-Hellman Protocols For Secure Group Communication Over Ad Hoc Networks, Yong Wang, Byrav Ramamurthy, Xukai Zou

School of Computing: Conference and Workshop Papers

The security of the two party Diffie-Hellman key exchange protocol is currently based on the discrete logarithm problem (DLP). However, it can also be built upon the elliptic curve discrete logarithm problem (ECDLP). Most proposed secure group communication schemes employ the DLP-based Diffie-Hellman protocol. This paper proposes the ECDLP-based Diffie-Hellman protocols for secure group communication and evaluates their performance on wireless ad hoc networks. The proposed schemes are compared at the same security level with DLP-based group protocols under different channel conditions. Our experiments and analysis show that the Tree-based Group Elliptic Curve Diffie-Hellman (TGECDH) protocol is the best in …


Spatial Correlation-Based Collaborative Medium Access Control In Wireless Sensor Networks, Mehmet C. Vuran, Ian F. Akyildiz Jan 2006

Spatial Correlation-Based Collaborative Medium Access Control In Wireless Sensor Networks, Mehmet C. Vuran, Ian F. Akyildiz

School of Computing: Faculty Publications

Wireless Sensor Networks (WSN) are mainly characterized by dense deployment of sensor nodes which collectively transmit information about sensed events to the sink. Due to the spatial correlation between sensor nodes subject to observed events, it may not be necessary for every sensor node to transmit its data. This paper shows how the spatial correlation can be exploited on the Medium Access Control (MAC) layer. To the best of our knowledge, this is the first effort which exploits spatial correlation in WSN on the MAC layer. A theoretical framework is developed for transmission regulation of sensor nodes under a distortion …


Eraid: Conserving Energy In High Performance Raid Systems With Conventional Disks, Dong Li, Jun Wang Jan 2006

Eraid: Conserving Energy In High Performance Raid Systems With Conventional Disks, Dong Li, Jun Wang

School of Computing: Technical Reports

Recently energy consumption becomes an ever critical concern for both low-end and high-end storage server and data centers. A majority of existing energy conservation solutions resort to multi-speed disks. However, current server systems are still built with conventional disks.
In this paper, we propose an energy saving policy, eRAID, for conventional disk based RAID-1 systems. eRAID saves energy by spinning down partial or entire mirror disk group with predictable performance degradation. The heart work of eRAID is to develop an accurate dynamic performance control (including disk power management) scheme. To guarantee service quality, the dynamic performance control works for two …


Helping End-User Programmers “Engineer” Dependable Software, Gregg Rothermel Jan 2006

Helping End-User Programmers “Engineer” Dependable Software, Gregg Rothermel

School of Computing: Conference and Workshop Papers

Not long ago, most software was written by professional programmers, who could be presumed to have an interest in software engineering methodologies and in tools and techniques for improving software dependability. Today, however, a great deal of software is written not by professionals but by end-users, who create applications such as multimedia simulations, dynamic web pages, and spreadsheets. Applications such as these are often used to guide important decisions or aid in important tasks, and it is important that they be sufficiently dependable, but evidence shows that they frequently are not. For example, studies have shown that a large percentage …


Spatio-Temporal Characteristics Of Point And Field Sources In Wireless Sensor Networks, Mehmet C. Vuran, Ӧzgür B. Akan Jan 2006

Spatio-Temporal Characteristics Of Point And Field Sources In Wireless Sensor Networks, Mehmet C. Vuran, Ӧzgür B. Akan

School of Computing: Conference and Workshop Papers

Wireless Sensor Networks (WSN) are comprised of densely deployed sensor nodes collaboratively observing and communicating extracted information about a physical phenomenon. Dense deployment of sensor nodes makes the sensor observations highly correlated in the space domain. In addition, consecutive samples obtained by a sensor node are also temporally correlated for the applications involving the observation of the variation of a physical phenomenon. Based on the physical characteristics and dispersion pattern over the area, the phenomenon to be observed can be modeled as point source or field source. Clearly, understanding the spatio-temporal correlation characteristics of the point and field sources brings …


A Cross-Layer Protocol For Wireless Sensor Networks, Ian F. Akyildiz, Mehmet C. Vuran, Ӧzgür B. Akan Jan 2006

A Cross-Layer Protocol For Wireless Sensor Networks, Ian F. Akyildiz, Mehmet C. Vuran, Ӧzgür B. Akan

School of Computing: Conference and Workshop Papers

Severe energy constraints of battery-powered sensor nodes necessitate energy-efficient communication protocols in order to fulfill application objectives of wireless sensor networks (WSN). However, the vast majority of the existing solutions are based on classical layered protocols approach. It is much more resource-efficient to have a unified scheme which melts common protocol layer functionalities into a cross-layer module for resource-constrained sensor nodes. To the best of our knowledge, to date, there is no unified cross-layer communication protocol for efficient and reliable event communication which considers transport, routing, medium access functionalities with physical layer (wireless channel) effects for WSNs.
In this paper, …


Cross-Layer Analysis Of Error Control In Wireless Sensor Networks, Mehmet C. Vuran, Ian F. Akyildiz Jan 2006

Cross-Layer Analysis Of Error Control In Wireless Sensor Networks, Mehmet C. Vuran, Ian F. Akyildiz

School of Computing: Conference and Workshop Papers

Severe energy constraints and hence the low power communication requirements amplify the significance of the energy efficient and preferably cross-layer error control mechanisms in Wireless Sensor Networks (WSN). In this paper, a crosslayer methodology for the analysis of error control schemes in WSNs is presented such that the effects of multi-hop routing and the broadcast nature of the wireless channel are investigated. More specifically, the cross-layer effects of routing, medium access and physical layers are considered. This analysis enables a comprehensive comparison of forward error correction (FEC) and automatic repeat request (ARQ) in WSNs.
FEC schemes improve the error resiliency …


A Constraint-Based Approach To Solving Minesweeper, Ken Bayer, Josh Snyder, Berthe Y. Choueiry Jan 2006

A Constraint-Based Approach To Solving Minesweeper, Ken Bayer, Josh Snyder, Berthe Y. Choueiry

School of Computing: Conference and Workshop Papers

·Motivate the students for the study of Constraint Processing (CP). Minesweeper is perfect to this end because it allows us to illustrate the use of CP algorithms in a familiar context and show how they operate.

·Understand and demystify humans’ fascination with puzzles.

·Discourage graduate students from losing too much time playing the game by making a program that plays the game for them.


Burrows Dug By Large Vertebrates Into Rain-Moistened Middle Jurassic Sand Dunes, David B. Loope Jan 2006

Burrows Dug By Large Vertebrates Into Rain-Moistened Middle Jurassic Sand Dunes, David B. Loope

Department of Earth and Atmospheric Sciences: Faculty Publications

In south-central Utah, eolian cross-strata of the Escalante Member of the Entrada Sandstone contain inclined, cylindrical burrows up to 63 cm in diameter and 305 cm long. Of the 14 large tunnels located during this study, 12 descend from second- and third-order bounding surfaces that formed on the lee slopes of large dune ridges, well above the water table. The tunnels are inclined 15°–22°; one tunnel ends in an expanded chamber. Eolian cross-strata fill proximal portions of four of the tunnels and indicate that after abandonment, sand drifts migrated as much as a meter into the open shafts. Structureless sand …