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A Theoretical Study On Silicon And Iii-V Compound Nanotubes, Engi̇n Durgun, Sali̇m Çiraci

Turkish Journal of Physics

In this paper we present a theoretical study on single-wall silicon and III-V compound nanotubes. First principles plane wave calculations within density functional theory are used to predict energetics and electronic structures of armchair and zigzag nanotubes. The stability of tubular structures is further investigated at finite temperature by ab initio molecular dynamics calculations. Our results indicate that (n,0) zigzag and (n,n) armchair single-wall Si nanotubes are stable for n >= 6. Mechanically, the Si nanotubes are radially soft, however they are strong against axial deformations. Electronic analysis showed that zigzag nanotubes are metallic for n Keywords: silicon, nanotube, first …

Electrical Properites Of Superconducting Cross - (Nano) Whiskers Junction, Serdar Altin, Eyüphan Yakinci, Yakup Balci, M. Ali̇ Aksan

Turkish Journal of Physics

Bi-2212 superconducting single crystal (nano) whiskers have been fabricated by annealing a melt-quenched (glass) Bi_3Sr_2Ca_2Cu_3O_x precursor. A couple of (nano) Whiskers obtained were placed crosswise on a YSZ single crystal substrate and then heat treated at 830 C for 25 minute to form nano-scale junction. The T_c of each nano-whisker was found to be 85 K and the critical current density, J_c, of the whiskers was calculated to be 1177 Acm^{-2} at zero field. The I-V characteristics of the nano-junction at 30 K were found to show a multiple-branch structure, which is the main behavior of the Josephson junction.

Detailed Geochronology Of The Mississippi Sound During The Late Holocene, Brian Velardo

LSU Master's Theses

The Mississippi Sound is a bar-built estuary that parallels the Mississippi Coast. It is bounded on the west by the St. Bernard lobe of the Mississippi River delta, Mobile Bay to the east, and the Gulf Coast barrier islands to the south. Few studies have investigated the late Holocene history of Mississippi Sound. In the present study, historical deposition in the Sound has been investigated using core data collected throughout the western, central, and eastern Mississippi Sound. The sediments within Mississippi Sound compose a complex depositional system that have responded to changes in sea level and hydrodynamics. Two factors that …

A Comparison Of The Scientific Achievement Of Students Using Ited, Itbs, And District-Developed Performance Assessments, Marcia Ruth Powell

Graduate Research Papers

The West Delaware school district is located in northeast Iowa, halfway between Waterloo and Dubuque along highway 20. The district has approximately 650 students in grades 9-12 and employs 48 teachers. Four of these teachers teach science full-time, and two teachers from other departments pick up extra courses. The 150+ 8th grade students represented in this study were taught by two different science teachers, who also teach 7th grade science. 8th grade science is taught in a 45 minute day for the entire year, while 9th and 10th graders are taught on a 90 minute block schedule, with each class …

An Inquiry Of Plants, Brad D. Wymer

Graduate Research Papers

This project has been completed to improve the quality of instruction of the biology students at Iowa City West High School. A curricular unit covering plants has been designed keeping in mind the National Science Education Standards, the curricular benchmarks established by the Iowa City Community School District and the current research on how people learn. Applicable research that supports the inquiry approach to teaching biology, an outline of the daily events that occur during the course of the curricular unit, and examples of the use of inquiry teaching styles are included throughout this work.

Small Group Math Instruction : Is It Beneficial In A Seventh Grade Classroom?, Joellen A. Schwab

Graduate Research Papers

Is small group math instruction a beneficial practice in a regular seventh grade classroom? Two teachers and approximately 500 students were involved in a study to address that question. The study occurred from the fall of 2002 through the fall of 2004 at Hoover Middle School in Waterloo, Iowa. Before small group math instruction was implemented, students averaged approximately 61 % on chapter tests, while after its implementation students were scoring an average of 76%. Procedures included both pre and post test data analysis.

Small groups were created based on student achievement. There were three main groups: low, middle, and …

Utilizing Geographic Education Research To Increase Learning In A Seventh Grade Geography Course, Eric Uwe Schulz

Graduate Research Papers

The purpose of this paper is to review the current condition of geography education, to examine current research in geographic education, and to create a plan to improve student learning in my classroom. It outlines the re-emergence of geography education in the secondary setting and considers the quality of the national geography standards. A descriptive narrative of current geographic education research is used to determine best instructional practice and is aligned with Colorado's Model Geography Standards to link the current research with curriculum. The results of the research are then used to evaluate and improve the curriculum, pedagogy, and assessment …

Peer Tutoring And Technology Integration : You Too Can Make It Happen!, Brandy Smith

Graduate Research Papers

Technology is motivating to students and brings with it a sense of empowerment. This article looks at a successful model of technology integration. This model comes in the form of an after-school club called the "Tech Club" built upon a peer tutoring model. A lead teacher trained third grade student leaders, or the "Tech Kids" to facilitate technology "how-to" sessions in their classrooms. After learning technology basics, this core group of Tech Kids visited different third grade classrooms to teach their peers this magic. This article explains how this peer tutoring model greatly empowered these third grade students and allowed …

Implementing Distributed Practice, Christi Sires

Graduate Research Papers

Distributed practice is a daily routine where students are exposed to a math problem, asked to solve it, and then explain how they solved it. The idea of short intervals of instruction over a period of time can have remarkable results. This instructional strategy has been cited in numerous research studies, an indication that it may be successful in helping students better understand how they can solve mathematical problems.

This study will try to determine the growth of Jewett Elementary's first grade students as they were exposed to distributed practice over a period of time from first to second quarter …

Using Technology In A Social Studies Classroom, Cari R. Teske

Graduate Research Papers

Technology in education is nothing new. The quality of the type of instruction involving technology is worth analyzing. This review provides insight into implementation strategies and the 'best practices' of the integration of technology. It defines the roles teachers and administrators must play in order to have high-quality instruction. Throughout this review emphasis will be put on the strength that technology can bring to the social studies curriculum. And, how together social studies and technology can bring education to a more balanced approach to instruction. To create a type of instruction that emphasizes the equal support of all areas of …

Elements Of Leadership In Education : A Reflective Essay, James D. Walser

Graduate Research Papers

As I grew up, my interest in various academic subject areas and my enjoyment of school caused me to become interested in education as a career. I felt that I could make a contribution to the lives of my students. My specific interest in mathematics and my personality lent themselves to classroom instruction. Although I have experienced some discouraging days, I still remain confident concerning a career in education.

The Impact Of Parental Involvement On Children's Literacy Development, Annette L. Wohlers

Graduate Research Papers

Reading is a growing concern in the United States. Many students are leaving the educational system not ready to deal with the literary demands of everyday life and/or higher education. Factors that support students' growth in reading were reviewed. One specific factor that has a significant impact on literacy, which was a focus, was involvement of parents. What parents can do to assist their children's literacy development and attainment were also reviewed. A parent pamphlet design on reading at home came about from obtained information from the reviews.

English Language Learners In The Integrated Middle School Science Classroom, Julie A. Fee

Graduate Research Papers

This paper will answer three questions relating to limited English-proficiency students. First, what historical changes have occurred to improve education for the LEP student? Second, what information do teachers with adolescent LEP students, especially students who have recently immigrated, need in order to run a happy and successful class? Last, what strategies and philosophies should be used to help ESL students compete academically with their American born classmates?

Using Web-Based Material To Support Secondary Science Curriculum, Ghadeer Filimban

Graduate Research Papers

Web-based materials have introduced a new way of supporting students' learning and teachers' knowledge of the secondary science curriculum. However it is difficult to know which materials to use and how to use them. This review discussed some of the methods for teaching science, web-based materials that support these methods, how the Internet can add to teachers' knowledge, and some negative effects of using this technology. This review shows how teachers can integrate web-based materials into their teaching strategies, and can help teachers who have integrated them to be aware of the negatives of using the Internet in the classroom. …

Fracture Behavior Of Wood Plastic Composite (Wpc), Gi Young Jeong

LSU Master's Theses

In this study, the effect of notch length on impact strength and fracture toughness was examined to exploit the use of wood plastic composite (WPC) as structural materials. Impact and fracture toughness test methods and estimation procedures were carried out. To evaluate the impact strength of WPC, five different notch sizes with two different fiber orientations on the load head were prepared. In terms of fracture mechanics, notch length was converted to stress concentration factor and the relationship between stress concentration factor and impact strength was determined. Fracture surface of impact specimens was investigated to evaluate the fracture mechanism of …

An In-Situ Capping Design For The Remediation Of Petroleum Contaminated Sediments, Melanie Krystle Harris

LSU Master's Theses

Historical disposal practices used by oil companies have caused the accumulation of contaminated sediments in their nearby lakes and ponds. These companies are now faced with the challenge of remediating the bodies of water that contain these contaminated sediments. The contaminants that remain in the sediment continue to pose a threat to human health and the environment. For example, high concentrations of polycyclic aromatic hydrocarbons (PAHs), which are still present in the bottom sediments can have toxic effects on aquatic life. One form of remediation for this problem is In-Situ Capping (ISC), which is defined as a method whereby material …

Transform Techniques And Non-Stationarity With An Emphasis On Network Applications, Phat Piron

LSU Master's Theses

The recent years brought a phenomenal development of Internet. It is, therefore, important to find some ways to improve the performances. The first step in this direction is the characterization and modeling of the network traffic. It has been tested that the network traffic behaves like a self-similar process, while packets interarrivals time possess the long-range dependence property. In particular, we model them by using fractional Brownian motion and fractional Gaussian noise, respectively. Note that, the former is just the cumulative sum of the latter. By using these concepts, the traffic characterization reduces to the estimation of one value: the …

Cover And Contents

Turkish Journal of Biology

No abstract provided.

3-Dimensional Flow Measurements In Square Coaxial Jets, Thomas Lagarde

LSU Master's Theses

Results from un-forced experiments conducted in the three-dimensional flow emanating from coaxial contoured nozzles with square cross section and parallel sides are presented and discussed. Two experiments were conducted with the inner to outer jet nominal velocity ratio equal to l=0.5 and l=1.5. The Reynolds number of the outer jet based on the hydraulic diameter of the outer nozzle exit was in both cases 16,000. A multi-position hot-wire anemometry method was used for measurements in the three-dimensional turbulent flow using a dual film sensor (X-probe). A methodology was developed and implemented to derive the mean-velocity components and Reynolds stresses corrected …

Identification Of 'Structural Alerts' And Associated Mechanisms Of Action Of Mammary Gland Carcinogens In Female Rodents, Shanna Tommika Moss

LSU Master's Theses

A new structure-activity relationship (SAR) approach to modeling was utilized to study mammary gland carcinogens. A set of chemicals tested for mammary tumorigenesis that have been analyzed in the Carcinogenic Potency Database (CPDB) were subjected to several computational analyses in an attempt to predict each chemical’s carcinogenic potential. A total of six learning sets (rat and mouse mammary gland carcinogen, CPDB rat and mouse, and female-specific rodent models) were developed and validated using a SAR modeling algorithm called categorical-SAR (cat-SAR). The predictive cat-SAR program evaluates active and inactive compounds of known biological activity and predicts their biological activity from this …

Secure 3g User Authentication In Ad-Hoc Serving Networks, Lyn L. Evans

LSU Master's Theses

The convergence of cellular and IP technologies has pushed the integration of 3G and WLAN networks to the forefront. With 3G networks' failure to deliver feasible bandwidth to the customer and the emerging popularity, ease of use and high throughput of 802.11 WLANs, integrating secure access to 3G services from WLANs has become a primary focus. 3G user authentication initiated from WLANs has been defined by an enhancement to the extensible authentication protocol, EAP, used to transport user authentication requests over WLANs. The EAP-AKA protocol executes the 3G USIM user challenge and response authentication process over the IP backbone for …

A Programmable Cmos Decimator For Sigma-Delta Analog-To-Digital Converter And Charge Pump Circuits, Raghavendra Reddy Anantha

LSU Master's Theses

PROGRAMMABLE DECIMATOR FOR SIGMA-DELTA ANALOG-TO-DIGITAL CONVERTER: In this work a programmable decimator design has been presented in 1.5 μm n-well CMOS process for integration with an existing modulator to form a sigma-delta analog-to-digital converter (ADC). The decimator is implemented using a second order Cascaded Integrator Comb (CIC) filter and can be programmed to work with two different oversampling ratios of 64 and 16. The input to the decimator is provided from a first order modulator. With oversampling ratios of 64 and 16, an output resolution of 10-bit and 7-bit, respectively are achieved for the ADC. The ADC can be operated …

On Torsion-Free Crawley Groups, Brendan Goldsmith, A. L. S. Corner, R. Gobel

Articles

The notion of a Crawley p-group is well known in Abelian group theory. In this present work, a corresponding concept is introduced for torsion-free groups. The principal result, which uses the set-theoretic notions of the diamond and Martin’s axiom, establishes an independence result for N1-free Crawley groups.

An Explicit Mapping Between The Frequency Domain And The Time Domain Representations Of Nonlinear Systems, Marissa Condon, Rossen Ivanov

Articles

Explicit expressions are presented that describe the input-output behaviour of a nonlinear system in both the frequency and the time domain. The expressions are based on a set of coefficients that do not depend on the input to the system and are universal for a given system. The anharmonic oscillator is chosen as an example and is discussed for different choices of its physical parameters. It is shown that the typical approach for the determination of the Volterra Series representation is not valid for the important case when the nonlinear system exhibits oscillatory behaviour and the input has a pole …

Manev Potential And General Relativity, Rossen Ivanov, Emil Prodanov

Articles

Manevis classical potential is known to successfully modify Newtonian celestial mechanics, in accordance with the general-relativistic description. The idea of replacing the exact solution of Einsteinis equations, describing orbiting bodies, with a classical potential is widely used today. These models are not restricted to planetary motion only, but also include numerous interesting astrophysical phenomena such as accretion of matter around black holes or massive stars.

Zeros Of The Jost Function For A Class Of Exponentially Decaying Potentials, Daphne Gilbert, Alain Kerouanton

Articles

We investigate the properties of a series representing the Jost solution for the differential equation $-y''+q(x)y=lambda y$, $x geq 0$, $q in mathrm{L}({mathbb{R}}^{+})$. Sufficient conditions are determined on the real or complex-valued potential $q$ for the series to converge and bounds are obtained for the sets of eigenvalues, resonances and spectral singularities associated with a corresponding class of Sturm-Liouville operators. In this paper, we restrict our investigations to the class of potentials $q$ satisfying $|q(x)| leq ce^{-ax}$, $x geq 0$, for some $a>0$ and $c$ greator than 0.

Interaction Of Single Walled Carbon Nanotubes With Starch-Based Systems, Alan Casey, Gerald Farrell, Mary Mcnamara, Hugh Byrne, Gordon Chambers

Conference papers

The interaction of carbon nanotubes with soft organic molecules such as cyclodextrins and other saccharides has recently been shown to produce water-soluble composites. Such systems offer considerable advantages over polymer based composites due to their biocompatibility and noncovalent coupling which can potentially preserve the unique properties of the tubes. The mechanism of interaction of such systems has been proposed to be dominated by hydrophobic and hydrophilic interactions along the surface of the tube. In this study a number of composite systems have been formed with HiPco carbon nanotubes using starch and starch based polymers. The first composite formed with starch …

Temperature Dependent Spectroscopic Studies Of Hipco Swnt Composites, Sinead Keogh, Theresa Hedderman, Garrett Farrell, M Ruether, Elizabeth Gregan, Mary Mcnamara, Gordon Chambers, Hugh Byrne

Articles

No abstract provided.

Inquiry In Early Childhood Teacher Education: Reflections On Practice, Jane Tingle Broderick, Seong Bock Hong

ETSU Faculty Works

As teacher educators we work to make inquiry methodology explicit to help teacher candidates construct the link between theory and practice. Bringing inquiry learning into the early childhood curriculum method courses raises the potential for inquiry teaching practice for teacher candidates and models a constructivist practice in a higher education setting. Of the numerous curriculum studies available, few focus on methods of inquiry to guide adult learners’ to construct inquiry- teaching practices that they can transfer to their work with children. To improve the quality of our teaching in an Early Childhood Teacher Education program we researched and developed several …

Native Or Introduced? Fossil Pollen And Spores May Say. An Example From The Azores Islands, Jacqueline F.N. Van Leeuwen, Hanno Schäfer, W. O. Van Der Knapp, Tammy M. Rittenour, Svante Björck, Brigitta Ammann

Geosciences Faculty Publications

Aim: Among the various possible approaches to assess whether a species is native or introduced, the analysis of subfossil pollen and spores from natural archives is a valuable tool. Requirements include a sufficiently high taxonomic resolution of the pollen morphology, as well as sufficient temporal and spatial resolution. The aim of this study is to show the usefulness of this method in solving whether the taxon is native or introduced.

Location: The results are derived from two islands of the Azores: Flores and Pico. Methods: Analysis of pollen and spores in lake sediments; radiocarbon dating of the studied sediments.

Results: …