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2002

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Hybrid Sr Arq Scheme Using Trellis Coded Modulation For Point-To-Multipoint Communication Over Nonstationary Channels, Necmi̇ Taşpinar Jan 2002

Hybrid Sr Arq Scheme Using Trellis Coded Modulation For Point-To-Multipoint Communication Over Nonstationary Channels, Necmi̇ Taşpinar

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a type-I hybrid SR ARQ scheme using trellis coded modulation (TCM) for point-to-multipoint communication was analyzed on nonstationary broadcast channels where the channel bit error rate (BER) varies over time. A nonstationary channel is modelled as a two-state Markov chain. In the numerical calculations, it is found that, for a given p_{1} and \bar \varepsilon , the values of the average burst length \bar b have a very small influence on the throughput. Numerical results show that the throughput is better for values between 10 ^{-6} and 10 ^{-4}of average bit error rate \bar \varepsilon if the …

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Stability Analysis Of A Closed-Loop Control For A Pulse Width Modulated Dc Motor Drive, Fatma Gürbüz, Eyüp Akpinar Jan 2002

Stability Analysis Of A Closed-Loop Control For A Pulse Width Modulated Dc Motor Drive, Fatma Gürbüz, Eyüp Akpinar

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, the effect of the variation of amplitude and the chopping period of a PWM signal on the stability of a closed-loop control for a DC motor drive is investigated. First, the entire system is formulated as a Linear Quadratic (LQ) tracker with output feedback [1]. Then, stability analysis for the varying amplitude and the varying chopping period is carried out by the methods of root locus and the Jury test. Finally, stability limits obtained from a root locus and Jury test are checked by the simulation of the system in MATLAB.

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Cover And Contents Jan 2002

Cover And Contents

Turkish Journal of Electrical Engineering and Computer Sciences

No abstract provided.

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Stimulated Polarization In \Bf Linbo_{3} And \Bf Ba_{2}Nanb_{5}O_{15} Crystals, Süleyman Çabuk, Amirullah Mamedov Jan 2002

Stimulated Polarization In \Bf Linbo_{3} And \Bf Ba_{2}Nanb_{5}O_{15} Crystals, Süleyman Çabuk, Amirullah Mamedov

Turkish Journal of Physics

Thermally Stimulated Conductivity (TSC) and thermoelectret state in LiNbO_{3} and Ba_{2}NaNb_{5}O_{15} were measured as a function of temperature and time in dark and under UV excitation at liquid nitrogen temperature. Effect of polarization and the other external influences on thermoelectret were investigated. The thermal activation energy levels of traps were determined from TSC measurements as well as parameters (electric field, temperature, etc.) which are necessary for characterizing thermoelectrets were obtained.

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The B --> S G G Decay In The General Two Higgs Doublet Model, E. O. İltan Jan 2002

The B --> S G G Decay In The General Two Higgs Doublet Model, E. O. İltan

Turkish Journal of Physics

We study the decay width of the inclusive process b --> s g g in the two Higgs doublet model with three-level flavor changing neutral currents (model III). We analyse the dependencies of the differential decay width to the s- quark energy E_s and model III parameters, charged Higgs mass m_H_{^{±}} and Yukawa coupling \bar{\xi}_{N,bb}^D. We observe that there exist a considerable enhancement in the decay width for the relevant process. This enhancement can be reduced by choosing C_7^{eff} as negative or increasing the lower bound of m_H_{^{±}} to the large values. This is an interesting result which gives an …

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Properties Of Cold And Hot Polarized Nuclear Matter With Realistic Nucleon Nucleon Interaction, S. A. Moharram Jan 2002

Properties Of Cold And Hot Polarized Nuclear Matter With Realistic Nucleon Nucleon Interaction, S. A. Moharram

Turkish Journal of Physics

The Thomas-Fermi (TF) model is used to calculate the equation of state ofthermal polarized nuclear-matter (NM) within a nonrelativistic Hartree-Fock (HF) scheme. The potential employed is a new realistic version of the density-dependent M3Y effective nucleon-nucleon (NN) interaction where the Yukawa strengths are based on the G-matrix of the Paris interaction. To study the basic properties of asymmetric nuclear matter, this potential is generalized by introducing spin and spin-isospin components into the original M3Y effective NN interaction. The resulting equation of state (EOS) is soft. The results obtained are in reasonable agreement with previous theoretical estimates.

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Microstructure And Critical Current Of Hot-Pressed Ybco Ceramics, Şadan Özcan, Tezer Firat, Engi̇n Özdaş Jan 2002

Microstructure And Critical Current Of Hot-Pressed Ybco Ceramics, Şadan Özcan, Tezer Firat, Engi̇n Özdaş

Turkish Journal of Physics

The effect of hot-pressing (HPing) on the densification and the superconducting properties of YBCO were investigated. The phases and microstructure were analysed by XRD and SEM and transport properties were studied by I-V and AC susceptibility measurements. Relative density up to 93% and critical current density of 509 A/cm^{2} at 77 K were achieved through uniaxial HPing at 800°C under 325 kg/cm^{2} pressure for 4 hours. HPing raised the J_{c} from 80 A/cm^{2} to 509 A/cm^{2}. These results and AC susceptibility measurements reveal that the weak links or pinning forces were improved by increasing HPing pressure.

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Revised Stratigraphy And Facies Analysis Of Palaeocene-Eocene Supra-Allochthonous Sediments (Denizli, Sw Turkey) And Their Tectonic Significance, Hasan Sözbi̇li̇r Jan 2002

Revised Stratigraphy And Facies Analysis Of Palaeocene-Eocene Supra-Allochthonous Sediments (Denizli, Sw Turkey) And Their Tectonic Significance, Hasan Sözbi̇li̇r

Turkish Journal of Earth Sciences

A non-metamorphosed sedimentary sequence of Late Palaeocene-Eocene age exposed to the south of Dereköy Village (east of Denizli) was formerly interpreted as the uppermost part of the Menderes Massif. However, detailed field data indicates that the Dereköy succession rests unconformably on the Lycian ophiolitic mélange and thus cannot be accepted as a part of the Menderes sequence. The Dereköy succession consists of shelf to sub-marine sedimentary deposits that begin with a transgressive basal conglomerate, followed by limestone and then grading upward into clastic turbidites. The clastic beds have intra-basinal and extra-basinal fragments derived from carbonate lenses and the Lycian thrust …

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Mid-Ordovician (Late Darriwilian) Conodonts From The Southern-Central Taurides, Turkey: Geological Implications, Hüseyi̇n Kozlu, M. Cemal Göncüoğlu, Graciela N. Sarmiento, M. Ali̇ Gül Jan 2002

Mid-Ordovician (Late Darriwilian) Conodonts From The Southern-Central Taurides, Turkey: Geological Implications, Hüseyi̇n Kozlu, M. Cemal Göncüoğlu, Graciela N. Sarmiento, M. Ali̇ Gül

Turkish Journal of Earth Sciences

The Tekmen Member of the Seydişehir Formation of the Silifke-Aydıncık Nappe is exposed between the towns Silifke and Aydıncık, in the central Taurides, southern Turkey. The member is composed of sandy limestones with interbeds of reddish shales. Distinctive depositional features of the carbonates and associated siliciclastics are suggestive of a mixed carbonate-siliciclastic tempestite-type deposition in a shelf environment. The conodont fauna from the Tekmen Member includes taxa that are known from the Baltoscandian region and are referred to the Darriwilian, being the first Middle-Ordovician finding from Turkey. A late Darriwilian (late Lasnamägian to Uhakun) age migth be attributed to the …

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Tertiary Terrestrial To Shallow Marine Deposition In Central Anatolia: A Palynological Approach, Funda Akgün, Erhan Akay, Burhan Erdoğan Jan 2002

Tertiary Terrestrial To Shallow Marine Deposition In Central Anatolia: A Palynological Approach, Funda Akgün, Erhan Akay, Burhan Erdoğan

Turkish Journal of Earth Sciences

In central Turkey the Çankırı Basin developed between the Kırşehir and Sakarya continents as a collisional basin during the Tertiary. Along the southern border, between Yozgat and Yerköy, the basin fill predominantly comprises continental and shallow marine facies, and overlies the Late Cretaceous Kırşehir Block unconformably. The Yoncalı formation (shallow marine sandstones, shales and limestone lenses), the İncik formation (terrestrial conglomerates and sandstones) and the Bayat formation (subaerial lavas and pyroclastic rocks) are Middle to Late Eocene in age and grade laterally and vertically into each other. These units are unconformably overlain by a Middle Miocene continental sequence that is …

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Distribution And Origin Of Clay Minerals In Konya Neogene Sedimentary Basin, Central Anatolia, Turkey, Selahatti̇n Kadi̇r, Zehra Karakaş Jan 2002

Distribution And Origin Of Clay Minerals In Konya Neogene Sedimentary Basin, Central Anatolia, Turkey, Selahatti̇n Kadi̇r, Zehra Karakaş

Turkish Journal of Earth Sciences

Neogene sediments having both fluvial and lacustrine characteristics are widespread in the Konya region of central Anatolia. The fluvial units are typically green in colour and thick at the margin of the basin and thinning laterally basinwards. The lacustrine sediments are represented by white, beige and cream, pure, dolomitic, sandy and clayey limestone alternating with claystone. Grain size, components and matrix of the fluvial and lacustrine sediments decrease from the margin of the basin toward its center. Smectite and chlorite in detrital fluvial sediments are associated with amphibole, illite and quartz, while sepiolite and palygorskite formed diagenetically in the carbonate …

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The Role Of Crustal Fluids In Strike-Slip Tectonics: New Insights From Magnetotelluric Studies, Martyn Unsworth Jan 2002

The Role Of Crustal Fluids In Strike-Slip Tectonics: New Insights From Magnetotelluric Studies, Martyn Unsworth

Turkish Journal of Earth Sciences

The presence of fluids in the Earth's crust can dramatically change the rheology and may control a wide range of tectonic processes, especially in regions characterized by strike-slip deformation. Fluids such as water and partial melt change the electrical resistivity of the subsurface and may be detected through geophysical techniques that remotely sense electrical resistivity. For imaging to crustal and upper mantle depths, the most useful technique is magnetotellurics (MT) that uses natural electromagnetic waves as an energy source. Magnetotelluric studies of the Tibetan Plateau have detected a widespread mid-crustal layer of partial melting across almost the entire north-south extent …

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The Silistar Intrusive, Eastern Srednogorie Zone, Bulgaria: Structural Data And Potential For Porphyry Copper And Epithermal Systems, Radoslav Nakov, Thomas Kerestedjian, Angel Kunov Jan 2002

The Silistar Intrusive, Eastern Srednogorie Zone, Bulgaria: Structural Data And Potential For Porphyry Copper And Epithermal Systems, Radoslav Nakov, Thomas Kerestedjian, Angel Kunov

Turkish Journal of Earth Sciences

The Late Cretaceous Silistar intrusion comprises of gabbros, gabbro-diorites to quartz-diorites and aplites, that were emplaced into a volcano-sedimentary succession of similar age. Structural data suggest that this intrusion is part of a larger, partially exposed body. A dense network of primary and secondary joints, in many places filled with various ore and gangue minerals, is a conspicuous feature of the intrusion. Hydrothermal alteration affecting the intrusion and the wall rocks includes: uralitization (amphibole±epidote), secondary biotitization and propylitization. Propylitic alteration occurred in two stages: high temperature (epidote-actinolite-chlorite) and middle to low temperature (sericite-chlorite-carbonate-epidote and chlorite-sericite-carbonate). Products of later alteration events …

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Obituary Prof. Dr. Orhan Kaya [4th October 1937-24th November 2002] By, Tanju Kaya Jan 2002

Obituary Prof. Dr. Orhan Kaya [4th October 1937-24th November 2002] By, Tanju Kaya

Turkish Journal of Earth Sciences

No abstract provided.

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Obituary Prof. Dr. Kâzım Ergi̇n [21 May 1915-24 November 2002] By, Tuncay Taymaz Jan 2002

Obituary Prof. Dr. Kâzım Ergi̇n [21 May 1915-24 November 2002] By, Tuncay Taymaz

Turkish Journal of Earth Sciences

No abstract provided.

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Quantification Of The Spatial Gradient Of Local Volume Fraction From Tomography Images, Yongping Wang Jan 2002

Quantification Of The Spatial Gradient Of Local Volume Fraction From Tomography Images, Yongping Wang

LSU Master's Theses

Asphalt concrete has three constituents: aggregate, asphalt binder and air voids. In the mixture, aggregates serve as a skeleton of the mixture; asphalt serves as a binder to hold the aggregates together; and air voids prevent asphalt concrete from bleeding to avoid plastic mixes. The properties of asphalt concrete are controlled by the interaction of these three components. In asphalt concrete, asphalt binder, voids and aggregates are not uniformly distributed. The local volume fractions of these constituents vary with spatial locations. As a result, there exist a spatial gradient of the local volume fractions between two locations. Due to the …

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School Readiness: Characteristics, Viewpoints, And Guidelines For Developing An Effective Kindergarten Program, Vicki A. Zweibohmer Jan 2002

School Readiness: Characteristics, Viewpoints, And Guidelines For Developing An Effective Kindergarten Program, Vicki A. Zweibohmer

Graduate Research Papers

This study examined the recent literature on the subject of school readiness. Positive viewpoints, as well as negative viewpoints, associated with school readiness were discussed. Guidelines were presented for developing an effective kindergarten program with regard to school readiness. Also, conclusions were drawn from the current literature and recommendations were made for future kindergarten programs

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The Production Of A School District Video For Promotional Purposes, Rodney R. Zehr Jan 2002

The Production Of A School District Video For Promotional Purposes, Rodney R. Zehr

Graduate Research Papers

Video production for educational purposes is becoming more popular in American schools today because of the advancement of technology. With the development of digital cameras, digital video, and various forms of digital-editing software for the computer, American schools can now tap into a new and growing form of media that will continue to grow in popularity as technology continues to advance in the future. 1 The video project for the Mason City Community School District in Mason City, Iowa was initiated as a graduate project through the University of Northern Iowa in Cedar Falls, Iowa. This project was started because …

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Motivation And Mandatory Standardized Testing: Utilizing The School Counselor As Consultant, Liaison, Trainer, And Advocate, Trent Taylor Jan 2002

Motivation And Mandatory Standardized Testing: Utilizing The School Counselor As Consultant, Liaison, Trainer, And Advocate, Trent Taylor

Graduate Research Papers

Since the publication of "A Nation at Risk" in 1983, the emphasis on using standardized testing has dramatically increased (Burke & Lombardi, 1998). Political candidates at all levels are using the issues of accountability and testing in campaign advertisements and as focal points to attack opponents. Today, hundreds of thousands of achievement and aptitude tests are administered each year in educational settings (Hood & Johnson, 1997).

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Literature Review : Using Humor With Children, Carol J. Aswegen Thornhill Jan 2002

Literature Review : Using Humor With Children, Carol J. Aswegen Thornhill

Graduate Research Papers

The purpose of this paper is to explore and review the literature on humor, particularly as it relates to interactions with children. Often adults, whether they are parents or teachers, devalue the use of humor in dealing with children. Research supports that humor is a beneficial component of social interactions, especially with children. Studies have shown that children are receptive to humor beginning at very young ages, and that their sense of humor is developed and finely tuned as they mature. Findings show that by using humor in social situations, stress levels can be de-escalated, defensive reactions are reduced--which in …

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A Preferred Vision For Administering Elementary/Secondary Schools : A Reflective Essay, Xina N. Zanders Jan 2002

A Preferred Vision For Administering Elementary/Secondary Schools : A Reflective Essay, Xina N. Zanders

Graduate Research Papers

All students need a safe and nurturing environment to receive a quality education. Principals should treat students as individuals judged by their character and learning style as well as their capabilities. To be an effective administrator and to establish a strong foundation, the principles of the Iowa Standards for School Leaders (ISSL) are used as guides. I will discuss each of the ISSL principles and explain how they influence my philosophy of educational leadership.

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Creating A User Friendly Website For The Boys & Girls Clubs Of Black Hawk County, Kimberly M. Carter Jan 2002

Creating A User Friendly Website For The Boys & Girls Clubs Of Black Hawk County, Kimberly M. Carter

Graduate Research Papers

Website design can be overwhelming for many viewers. Many times viewers discontinue using sites, because it.is not easy to navigate through the site. In creating the website for the Boys & Girls Clubs of Black Hawk County, user-friendliness was the focal point of the project. The Chief Professional Officer along with the staff at the Boys & Girls Clubs assisted with the development of a website by providing information that was to be included on the site. To ensure a professional look the designer relied on the four basic principles of design: contrast, repetition, alignment, and proximity. The design simplicity …

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Surfactant-Induced Relative Permeability Modifications For Oil Recovery Enhancement, Subhash C. Ayirala Jan 2002

Surfactant-Induced Relative Permeability Modifications For Oil Recovery Enhancement, Subhash C. Ayirala

LSU Master's Theses

Surfactants have been considered for enhanced oil recovery by reduced oil-water interfacial tension. However, these surfactants may enhance oil recovery via wettability alteration as well. This study experimentally determines the influence of surfactant type and concentration on oil recovery, oil-water relative permeabilities and wettability in reservoir rocks. Several coreflood experiments were conducted using Yates reservoir fluids in Berea rocks and two types of surfactants (nonionic and anionic) in varying concentrations. A coreflood simulator was used to calculate oil-water relative permeabilities by history matching recovery and pressure drop measured during the corefloods. These relative permeability variations were interpreted using Craig's rules-of-thumb …

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Cover And Contents Jan 2002

Cover And Contents

Turkish Journal of Biology

No abstract provided.

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Cover And Contents Jan 2002

Cover And Contents

Turkish Journal of Biology

No abstract provided.

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Decentralized And Adaptive Sensor Data Routing, Mengxia Zhu Jan 2002

Decentralized And Adaptive Sensor Data Routing, Mengxia Zhu

LSU Master's Theses

Wireless sensor network (WSN) has been attracting research efforts due to the rapidly increasing applications in military and civilian fields. An important issue in wireless sensor network is how to send information in an efficient and adaptive way. Information can be directly sent back to the base station or through a sequence of intermediate nodes. In the later case, it becomes the problem of routing. Current routing protocols can be categorized into two groups, namely table-drive (proactive) routing protocols and source-initiated on-demand (reactive) routing. For ad hoc wireless sensor network, routing protocols must deal with some unique constraints such as …

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Educational Leadership, Patricia Jean Bassett Jan 2002

Educational Leadership, Patricia Jean Bassett

Digitized Theses and Dissertations (prior to 2008)

A PORTFOLIO SUBMITTED IN PARTIAL FULFILLAAENT OF THE REQUIREMENTS FOR CERTIFTCATTON IN EDUCATIONAL LEADER5HIP OF KENNESAW STATE UNIVERSITY

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K(Π, 1) For Artin Groups Of Finite Type, Colum Watt, Thomas Brady Jan 2002

K(Π, 1) For Artin Groups Of Finite Type, Colum Watt, Thomas Brady

Articles

This paper is a continuation of a programme to construct new K(π, 1)’s for Artin groups of finite type which began in [4] with Artin groups on 2 and 3 generators and was extended to braid groups in [3]. These K(π, 1)’s differ from those in [6] in that their universal covers are simplicial complexes. In [4] a complex is constructed whose top-dimensional cells correspond to minimal factorizations of a Coxeter element as a product of reflections in a finite Coxeter group. Asphericity is established in low dimensions using a metric of non-positive curvature. Since the nonpositive curvature condition is …

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A Partial Order On The Orthogonal Group, Colum Watt, Thomas Brady Jan 2002

A Partial Order On The Orthogonal Group, Colum Watt, Thomas Brady

Articles

We define a natural partial order on the orthogonal group and completely describe the intervals in this partial order. The main technical ingredient is that an orthogonal transformation induces a unique orthogonal transformation on each subspace of the orthogonal complement of its fixed subspace.

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On Unit Sum Numbers Of Rational Groups, Brendan Goldsmith, Christopher Meehan, S. Wallutis Jan 2002

On Unit Sum Numbers Of Rational Groups, Brendan Goldsmith, Christopher Meehan, S. Wallutis

Articles

The unit sum numbers of rational groups are investigated: the importance of the prime 2 being an automorphism of the rational group is discussed and other results are achieved by considering the number and distribution of rational primes which are, or are not, automorphisms of the group. Proof is given of the existence of rational groups with unit sum numbers greater than 2 but of finite value .

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