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A New Simulator For Hvdc/Ac Systems-Part I, Baktiar Zangeneh, Abbas Shoulaie

Turkish Journal of Electrical Engineering and Computer Sciences

A simulator with optimal step time (SOST) has been designed to investigate Large HVdc/ac systems. The adequacy and robustness of the simulator will be demonstrated by showing some important applications relevant to operation, operational planning and medium-term planing. Some of the features of our SOST simulator are optimal step time algorithm, interpolation, chatter removal, MATLAB interface, unlimited size of ac system, and Farsi command that help model complex power electronic circuits, provide fast and accurate results. On account of its reduced calculation effort and deterministic execution time, optimal-step simulation is a prerequisite for real-time performance. However, when simulating electromagnetic-transients behavior, …

A New Simulator For Hvdc/Ac Systems-Part Ii, Baktiar Zangeneh, Abbas Shoulaie

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a performance comparison (the focus of numerical simulation) of traditional simulation (TCS,TSE) with an optimal step time simulator (SOST) for large HVdc systems.In SOST, a Detailed simulation of HVdc converter behavior has been modified to include the automatic selection of optimal integration steps, frequency-dependent effects of an ac system, ac system phase and magnitude dynamics of voltage (particularly weak ac systems), control assessment and temporary over-voltage consequences. SOST, via graphical interfaces,provides fast and accurate information of electromechanical and the electromagnetic-transients behavior of a large HVdc/HVac system.

Cover And Contents

Turkish Journal of Electrical Engineering and Computer Sciences

No abstract provided.

Fiber Sums Of Genus 2 Lefschetz Fibrations, Denis Auroux

Turkish Journal of Mathematics

Using the recent results of Siebert and Tian about the holomorphicity of genus 2 Lefschetz fibrations with irreducible singular fibers, we show that any genus 2 Lefschetz fibration becomes holomorphic after fiber sum with a holomorphic fibration.

Galois Symmetry On Floer Cohomology, Kenji Fukaya

Turkish Journal of Mathematics

In this article, we define an action of \hat{\Bbb Z} on the A_{\infty} category whose objects are rational Lagrangian submanifolds together with some other data. The group \hat{\Bbb Z} is a Galois group of the (universal) Novikov ring (field) over Laurent polynomial field. By mirror symmetry it will corresponds to the algebraic fundamental group of a punctured disk which parametrize the maximal degenerate family of the mirror complex manifold.

On Cofinite Subgroups Of Mapping Class Groups, Mustafa Korkmaz

Turkish Journal of Mathematics

For every positive integer n, we exhibit a cofinite subgroup \Gamma_n of the mapping class group of a surface of genus at most two such that \Gamma_n admits an epimorphism onto a free group of rank n. We conclude that H^1 (\Gamma_n; {\mathbb Z}) has rank at least n and the dimension of the second bounded cohomology of each of these mapping class groups is the cardinality of the continuum. In the case of genus two, the groups \Gamma_n can be chosen not to contain the Torelli group. Similarly for hyperelliptic mapping class groups. We also exhibit an automorphism of …

A Monopole Homology For Integral Homology 3-Spheres, Weiping Li

Turkish Journal of Mathematics

To an integral homology 3-sphere Y, we assign a well-defined {\mathbb Z}-graded (monopole) homology MH_*(Y, I_{\eta}(\Theta; \eta_0)) whose construction in principle follows from the instanton Floer theory with the dependence of the spectral flow I_{\eta}(\Theta; \eta_0), where \Theta is the unique U(1)-reducible monopole of the Seiberg-Witten equation on Y and \eta_0 is a reference perturbation datum. The definition uses the moduli space of monopoles on Y \times {\mathbb R} introduced by Seiberg-Witten in studying smooth 4-manifolds. We show that the monopole homology MH_*(Y, I_{\eta}(\Theta; \eta_0)) is invariant among Riemannian metrics with same I_{\eta}(\Theta; \eta_0). This provides a chamber-like structure for …

Adjunction Inequality And Coverings Of Stein Surfaces, Stefan Nemirovski

Turkish Journal of Mathematics

A stronger form of the adjunction inequality is proved for immersed real surfaces in non simply-connected Stein surfaces. The result is applied to the geometry of Stein domains and analytic continuation on complex surfaces.

Comparing Open Book And Heegaard Decompositions Of 3-Manifolds, J. Hyam Rubinstein

Turkish Journal of Mathematics

We study the maximal value of the Euler characteristic of the pages of all open book decompositions of closed orientable 3-manifolds. In particular, we describe some examples where the minimal genus Heegaard splittings of such 3-manifolds give rise to open book decompositions and other examples where the simplest open book decomposition has larger maximal Euler characteristic of pages than the smallest genus Heegaard splittings. Also, special properties of the Heegaard splitting associated to an open book decomposition are given. Techniques of minimal surface theory and hyperbolic geometry are shown to be useful for such problems.

Abelian Fibred Holomorphic Symplectic Manifolds, Justin Sawon

Turkish Journal of Mathematics

We study holomorphic symplectic manifolds which are fibred by abelian varieties. This structure is a higher dimensional analogue of an elliptic fibration on a K3 surface. We investigate when a holomorphic symplectic manifold is fibred in this way, and are led to several natural conjectures. We then study the geometry of these fibrations. The expectation is that this point of view will prove useful in understanding holomorphic symplectic manifolds, and possibly lead to a classification.

Symplectic Surgeries From Singularities, Ivan Smith, Richard Thomas

Turkish Journal of Mathematics

We describe a variety of symplectic surgeries (not a priori compatible with Kaehler structures) which are obtained by combining local Kaehler degenerations and resolutions of singularities. The effect of the surgeries is to replace configurations of Lagrangian spheres with symplectic submanifolds. We discuss several examples in detail, relating them to existence questions for symplectic manifolds with c_1 > 0, c_1 = 0, c_1 < 0 in four and six dimensions.

Cover And Contents

Turkish Journal of Mathematics

No abstract provided.

Managing Protein In Spring Wheat With Aerial And Satellite Imagery, Dennis L. Wright Jr., Glen Ritchie, V. Philip Rasmussen, R. Douglas Ramsey, Doran Baker

Wildland Resources Faculty Publications

Nitrogen fertilizer application can help wheat growers increase crop value and marketability by increasing grain quality. Nitrogen (N) is often applied at heading as a method of increasing protein content and therefore quality of wheat. Our objectives were to obtain spectral signatures of wheat under various N rates (0, 72, 180, 234 kg N ha-1), test various spectral methods of identifying crop stress, and observe the grain protein response to a midseason N application. Spectral data from satellite and aerial platforms were compared to preseason N treatments and flag-leaf tissue samples. Spectral data correlated well with preseason and flag leaf …

Ferroelectric-Field-Induced Tuning Of Magnetism In The Colossal Magnetoresistive Oxide La1Àxsrxmno3, X. Hong, A. Posadas, A. Lin, C. H. Ahn

Xia Hong Publications

A ferroelectric field effect approach is presented for modulating magnetism in the colossal magnetoresistive oxide La_1-xSr_xMnO₃ (LSMO). The ferromagnetic Curie temperature of ultrathin LSMO films was shifted by 35 K reversibly using the polarization field of the ferroelectric oxide Pb(Zr_xTi_1-x)O₃ in a field effect structure. This shift was also observed in magnetoresistance measurements, with the maximum magnetoresistance ratio at 6 T increasing from 64% to 77%. This model system approach does not introduce substitutional disorder or structural distortion, demonstrating that regulating the carrier concentration alone changes the magnetic phase transition …

Scwds Briefs: Volume 18, Number 4 (January 2003)

Southeastern Cooperative Wildlife Disease Study: Publications

• The Latest on chronic wasting disease (CWD): Wisconsin, Illinois, Colorado, South Dakota, Wyoming, Nebraska, Saskatchewan
• The Wildlife Society (TWS) recently published a technical review and draft position statement on the confinement of wild ungulates within fenced enclosures--"Biological and Social Issues Related to Confinement of Wild Ungulates."
• Exotic Newcastle disease (END) was confirmed in backyard poultry flocks in southern California on October 1, 2002.
• Southern Tick-Associated Rash Illness (STARI): In the northeastern United States, Borrelia burgdorferi, the causative agent of Lyme disease, is maintained in nature through a cycle involving the white-footed mouse and other rodents …

Development Of A Low-Profile Bridge Rail For Test Level 2 Applications, Karla A. Polivka, Ronald K. Faller, Dean L. Sicking, John R. Rohde, John D. Reid, James C. Holloway

Mid-America Transportation Center: Final Reports and Technical Briefs

A low-profile bridge rail was developed for installations where pedestrians and/or site restrictions prevent the use of conventional bridge rails with transitions. The bridge rail design was constructed using a 22.86-m long reinforced concrete parapet. The entire system measured 508-mm high by 356-mm and 279-mm wide at the top and bottom surfaces, respectively.

The research study included one full-scale vehicle crash test, using a 3⁄4-ton pickup truck. The full- scale test, impacting at a speed of 70.0 km/hr and an angle of 27.1 degrees, was conducted and reported in accordance with the requirements specified in National Cooperative Highway Research Program …

Finite Subsets Of The Plane Are 18-Reconstructible, L. Pebody, A. J. Radcliffe, A. D. Scott

Department of Mathematics: Faculty Publications

We prove that every finite subset of the plane is reconstructible from the multiset of its subsets of at most 18 points, each given up to rigid motion. We also give some results concerning the reconstructibility of infinite subsets of the plane.

General Guidelines For The Establishment & Evaluation Of Invasive Species Early Detection & Rapid Response Systems

National Invasive Species Council

Preventing the introduction of invasive species is the first line of defense against invasions. However, even the best prevention efforts will not stop all invasive species introductions. Early detection and rapid response (ED&RR) efforts increase the likelihood that invasions will be addressed successfully while populations are still localized and population levels are not beyond that which can be contained and eradicated. Once populations are widely established, all that might be possible is the partial mitigation of negative impacts. In addition, the costs associated with ED&RR efforts are typically far less than those of long-term invasive species management programs.

The charge …

Yellow Jackets May Be An Underestimated Component Of An Ant-Seed Mutualism, Megan T. Bale, Jennifer A. Zettler, Bradford A. Robinson, Timothy P. Spira, Craig R. Allen

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Yellow jackets (Hymenoptera: Vespidae) are attracted to the typically ant-dispersed seeds of trilliums and will take seeds from ants in the genus Aphaeogaster.  To determine if yellow jacket, Vespulla maculifrons (Buysson), presence interferes with seed foraging by ants, we presented seeds of Trillium discolor Wray to three species (A. texana carolinesis Wheeler, Formica schaufussi Mayr, and Solenopsis invicta Buren) of seed-carrying ants in areas where vespids were present or excluded.  We found that interspecific aggression between yellow jackets and ants is species specific.  Vespid presence decreased average foraging time and increased foraging efficiency of two of the three …

Honors Composition: Historical Perspectives And Contemporary Practices, Annmarie Guzy

National Collegiate Honors Council Monographs

Chapter 1: Why Should We Research Honors Composition?
Chapter 2: Twentieth-Century Developments in Honors Education and Composition Instruction
Chapter 3: A Survey of Writing Courses and Projects in the Contemporary Honors Program
Chapter 4: Guidelines and Suggestions for Honors Composition Courses and Projects
Chapter 5: Conclusion
Appendix A: The Sixteen Major Features of a Full Honors Program
Appendix B: Cover Letter to Questionnaire for NCHC Member Programs
Appendix C: Questionnaire for NCHC Member Programs
Appendix D: Question Bank for Follow-up Interviews
Appendix E: Honors Thesis Rationale and Support for Azusa Pacific University
Appendix F: List of Follow-Up Interview Participants

The Over-Claiming Technique: Measuring Self-Enhancement Independent Of Ability, Delroy L. Paulhus, Peter D. Harms, M. Nadine Bruce, Daria C. Lysy

Leadership Institute: Faculty Publications

Overclaiming is a concrete operationalization of self-enhancement based on respondents’ ratings of their knowledge of various persons, events, products, and so on. Because 20% of the items are nonexistent, responses can be analyzed with signal detection formulas to index both response bias (over-claiming) and accuracy (knowledge). Study 1 demonstrated convergence of over-claiming with alternative measures of self-enhancement but independence from cognitive ability. In Studies 2–3, the validity of the overclaiming index held even when respondents were (a) warned about the foils or (b) asked to fake good. Study 3 also showed the utility of the over-claiming index for diagnosing faking. …

Implementation Plan For The Conservation Of Nebraska’S Eastern Saline Wetlands, Ted Lagrange, Terry Genrich, Glenn Johnson, Dan Schulz, Brent Lathrop

Nebraska Game and Parks Commission: Publications

Nebraska’s Eastern Saline Wetlands are the most limited and endangered wetland type and vegetation community in the State and are considered critically imperiled in Nebraska. These wetlands provide habitat for a variety of native plant and animal species that depend on a saline environment, including two endangered species.

Because of their location in and around the city of Lincoln, saline wetlands are ideally located to provide recreational opportunities and flood protection. Past impacts have resulted in the degradation of nearly 90% of the saline wetlands and those remaining face continued threats.

Although several programs are in existence to address saline …

A Live Collection Of A Pistolgrip From Nebraska, Steven C. Schainost

Nebraska Game and Parks Commission: Staff Research Publications

Freshwater mussels (Mollusca: Bivalvia: Unionidae) are one of Nebraska's more poorly known faunas. Studies have documented the presence of 31 species of which only 19 have been found either live or freshly dead. The remaining twelve species have only been found as weathered or subfossil shells, seven of which were considered to be extirpated including the pistolgrip (Tritogonia verrucosa). While a statewide survey never has been done there is distributional information available in several published papers and unpublished reports (Baxa 1981; Hoke 1983, 1994a, 1995, 1996, 1997; Roedel 1990; Lingle 1992; Freeman and Perkins 1992, 1997; Clausen and …

A Guide To Prairie And Wetland Restoration In Eastern Nebraska, Gerry Steinauer, Bill Whitney, Krista Adams, Mike Bullerman, Chris Helzer

Nebraska Game and Parks Commission: White Papers, Conference Presentations, and Manuscripts

This publication documents the restoration methods originally developed by Bill Whitney and later refined by himself and other ecologists from TNC, PRCT, NGPC and USFWS working in eastern Nebraska. Restoration of the following plant community types is covered in this document: tallgrass prairie, mixed-grass prairie, sand prairie, freshwater wet meadow and marsh, Rainwater Basin wet meadow and marsh, and saline wet meadow and marsh.

The methods we use are generally affordable and not complicated. To quickly summarize, we handpick and machine harvest seed, do little seed cleaning and broadcast plant with a fertilizer spreader. We do not mow annual weeds …

2003 Survey Of Priority Natural Communities In Jefferson County, Nebraska, Robert F. Steinauer

Nebraska Game and Parks Commission: White Papers, Conference Presentations, and Manuscripts

This survey was undertaken to update information on native plant communities and wildlife habitats in Nebraska to facilitate the development of the Nebraska Game and Parks Commission’s (NGPC) Comprehensive Wildlife Plan. The specific intent of the project was to identify and map all large blocks of privately owned native plant communities within the survey area. In 2003, the surveys focused on eastern Nebraska, specifically deciduous forest communities along the Missouri River, tallgrass prairies of southeastern Nebraska (Pawnee, Gage, Jefferson, and eastern Thayer counties), and loess mixed-grass prairies in central Nebraska. A brief survey of the Elkhorn River valley in Madison …

Focus Emu, March 11, 2003, Office Of Public Information

Focus EMU

No abstract provided.

Focus Emu, July 8, 2003, Office Of Public Information

Focus EMU

No abstract provided.

Focus Emu, February 4, 2003, Office Of Public Information

Focus EMU

No abstract provided.

Focus Emu, August 12, 2003, Office Of Public Information

Focus EMU

No abstract provided.

Focus Emu, February 28, 2003, Office Of Public Information

Focus EMU

No abstract provided.