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2008

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Collection Of Nitrate In A Denuder, Hannah Feig Jan 2008

Collection Of Nitrate In A Denuder, Hannah Feig

Undergraduate Journal of Mathematical Modeling: One + Two

Data are given for aerosol nitrate (NO3-) size distributions in the atmosphere as recorded by a cascade impactor and by an annular denuder. Using this data, our goal is to find the percent of nitrate in the atmosphere that the denuder is able to detect. This requires that we find the size distribution of nitrate that enters the denuder. From these data and calculations, we find that 32.8% of nitrate in the atmosphere can be detected by the denuder. Nitrate was measured to study its affects on seagrass in the Tampa Bay and to compare nitrate levels with …

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Critical Axial Load, Walt Wells Jan 2008

Critical Axial Load, Walt Wells

Undergraduate Journal of Mathematical Modeling: One + Two

Our objective in this paper is to solve a second order differential equation for a long, simply supported column member subjected to a lateral axial load using Heun's numerical method. We will use the solution to find the critical load at which the column member will fail due to buckling. We will calculate this load using Euler's derived analytical approach for an exact solution, as well as Euler's Numerical Method. We will then compare the three calculated values to see how much they deviate from one another. During the critical load calculation, it will be necessary to calculate the moment …

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Criteria Pollutant Concentration, Victor Neese Jan 2008

Criteria Pollutant Concentration, Victor Neese

Undergraduate Journal of Mathematical Modeling: One + Two

With the assistance of Assistant Professor Jeff Cunningham (Civil & Environmental Engineering Department, USF) a study was carried out pertaining to the amount of CO and NOx pollutants emitted from a highway having two lanes in each direction. The receptor of the pollutants is a hypothetical housing development located near the highway. The concentrations were found by utilizing information regarding meteorological conditions, estimated emissions rates, and distances from the highway less than or equaling 2 km.

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Democracy Uncaged, Suzanna Sherry Jan 2008

Democracy Uncaged, Suzanna Sherry

Constitutional Commentary, Vols 1–36 (1984–2022)

Book Review of Our Undemocratic Constitution: Where the Constitution Goes Wrong (and How We The People Can Correct It). By Sanford Levinson. Oxford University Press. 2006. Pp. ix + 233. Reviewed by: Suzanna Sherry

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Expanding Educational Opportunity Through School And Housing Choice, Myron Orfield, Nicholas Wallace Jan 2008

Expanding Educational Opportunity Through School And Housing Choice, Myron Orfield, Nicholas Wallace

Studies

This research paper details the prevalence of segregation in many Twin Cities schools.

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Photovoltaic Cells Based On Copper Phthalocyanine And Cadmium Sulfide Heterojunction, Sandeep Kumar Marda Jan 2008

Photovoltaic Cells Based On Copper Phthalocyanine And Cadmium Sulfide Heterojunction, Sandeep Kumar Marda

University of Kentucky Master's Theses

This work focuses on the solar cell based on the heterostructure formed between Copper Phthalocyanine (CuPc) and Cadmium Sulfide (CdS). Two different fabrication techniques were used for depositing the organic and inorganic layers of CuPc and CdS layers respectively. CuPc was deposited by electrodeposition while CdS was deposited by chemical bath deposition. Hybrid CdS/CuPc thin films were obtained from CdS films grown on Glass/ITO by chemical bath deposition followed by electrodeposition of CuPc onto these films and annealing at 250˚C after the deposition of each layer. The maximum open circuit voltage (Voc) and the short circuit current density …

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Evaluation Of 1,3,5 Trimethylbenzene Degradation In The Detailed Tropospheric Chemistry Mechanism, Mcmv3.1, Using Environmental Chamber Data, A. Metzger, J. Dommen, J. Duplissy, A. S.H. Prevot, J. Kleffmann, Yasin F. Elshorbany, A. Wisthaler, U. Baltensperger Jan 2008

Evaluation Of 1,3,5 Trimethylbenzene Degradation In The Detailed Tropospheric Chemistry Mechanism, Mcmv3.1, Using Environmental Chamber Data, A. Metzger, J. Dommen, J. Duplissy, A. S.H. Prevot, J. Kleffmann, Yasin F. Elshorbany, A. Wisthaler, U. Baltensperger

USF St. Petersburg Campus Faculty Publications

The degradation mechanism of 1,3,5-trimethyl-benzene (TMB) as implemented in the Master Chemical Mechanism version 3.1 (MCM) was evaluated using data from the environmental chamber at the Paul Scherrer Institute. The results show that the MCM provides a consistent description of the photo-oxidation of TMB/NO(x) mixtures for a range of conditions. In all cases the agreement between the measurement and the simulation decreases with decreasing VOC-NO(x) ratio and in addition with increasing precursor concentration. A significant underestimation of the decay rate of TMB and thus underestimation of reactivity in the system, consistent with results from previous appraisals of the MCM, was …

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Using Science Notebooks To Improve Writing Skills And Conceptual Understanding., Malcolm B. Butler, Catherine Nesbit Jan 2008

Using Science Notebooks To Improve Writing Skills And Conceptual Understanding., Malcolm B. Butler, Catherine Nesbit

USF St. Petersburg Campus Faculty Publications

The purpose of this article is to provide teachers with strategies for improving students' writing and deepening their conceptual understanding through the use of science notebooks. The strategies include using various resources and providing a variety of feedback opportunities for students. A sample science investigation and an accompanying science notebook entry illustrate these strategies.

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Context, Process And Change: The Status Of Prospective Teachers' Perceptions Of Teaching Process, Abdurrahman Sahin, Hulusi Cokadar, Muhammet Usak Jan 2008

Context, Process And Change: The Status Of Prospective Teachers' Perceptions Of Teaching Process, Abdurrahman Sahin, Hulusi Cokadar, Muhammet Usak

Essays in Education

Teacher candidates come to teacher education programs with beliefs shaped out of traditional contexts in their earlier lives. Those beliefs influence their new learning outcomes. It is therefore important for teacher education programs to identify the degree of perceptions that entry- and exit-level candidates hold. The purpose of this study is to identify and compare entry- and exit-level candidates’ degree of perceptions about teaching process and to understand if their perceptions relate to their personal variables. This is a descriptive study. The data were gathered by 28-item Teaching Process Perception Scale developed by the researchers. Collected from 267 teacher candidates …

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How Learning Mathematics Parallels Learning A Second Language And Implications For Teaching, Michael E. Matthews Jan 2008

How Learning Mathematics Parallels Learning A Second Language And Implications For Teaching, Michael E. Matthews

Essays in Education

This paper investigates the hypothesis that the language and symbols used to communicate mathematics (ML) can be considered a separate language from natural languages like English. Using definitions and characteristics found in natural languages, the paper investigates when and how these aspects show up in ML. ML is established as a separate language in most features. The paper continues by combining major findings in second language acquisition research with mathematics education research to develop suggestions to improve ML learning and thus improve mathematical learning.

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Optical And Structural Properties Of Zinc Based Nanoparticles Depend On Temperature And Molar Concentration, Alfonso Juan Hinojosa Jan 2008

Optical And Structural Properties Of Zinc Based Nanoparticles Depend On Temperature And Molar Concentration, Alfonso Juan Hinojosa

Physics Theses - Archive

Zinc based nanoparticles have great potential for use in radiation detection as well as uses in solid state lighting. In this thesis, we report the synthesis of ZnO: Eu3+ with the use of solid state diffusion at temperatures between 600 C and 700 C. We found that the emission of the nanoparticles depends particularly on the synthesis temperature as well as the molar concentration. The emission of the samples can be tuned to either the wavelengths of 495 nm and 611 nm. The formation of ZnO: Eu3+ has been identified with the use the Transmission Electron Microscope (TEM). The TEM …

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A Particle Filter Based Framework For Indoor Wireless Localization Using Custom Ieee 802.15.4 Nodes, Vijay Vasant Dixit Jan 2008

A Particle Filter Based Framework For Indoor Wireless Localization Using Custom Ieee 802.15.4 Nodes, Vijay Vasant Dixit

Computer Science and Engineering Theses - Archive

Locating people and objects as soon as possible and fair amount of precision has always been an important part of any organization or industry, especially in manufacturing, healthcare, and logistics. Systems that now have the ability to locate objects or people are called Real Time Location Systems (RTLS). They typically use small low-power transmitters called tags attached to assets (or worn by people) as well as sets of readers that map the location of these tags. Systems that map the longitude and attitude of an object are geo-location systems and generally use GPS for location mapping. Systems that map a …

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Dynacet: A Minimum-Effort Driven Dynamic Faceted Search System Over Structured Databases, Haidong Wang Jan 2008

Dynacet: A Minimum-Effort Driven Dynamic Faceted Search System Over Structured Databases, Haidong Wang

Computer Science and Engineering Theses - Archive

In this thesis, we propose minimum-effort driven navigational techniques for enterprise database systems based on the faceted search paradigm. Our proposed techniques dynamically suggest facets for drilling down into the database such that the cost of navigation is minimized. At every step, the system asks the user a question or a set of questions on different facets and depending on the user response, dynamically fetches the next most promising set of facets, and the process repeats. Facets are selected based on their ability to rapidly drill down to the most promising tuples, as well as on the ability of the …

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Modeling And Simulation Of A General Motors Conveyor System Using A Custom Decision Optimizer, Mirza Mohammad Lutfe Elahi Jan 2008

Modeling And Simulation Of A General Motors Conveyor System Using A Custom Decision Optimizer, Mirza Mohammad Lutfe Elahi

Computer Science and Engineering Theses - Archive

The temporal behavior of conveyor systems can be modeled using discrete event (DE) simulations. DE modeling provides a quick and cost effective method for analyzing complex problems as different scenarios can be tested rapidly without affecting the day to day activities of production systems. A simulation model coupled with decision optimization on routing choices enables the evaluation of different decision strategies.In the General Motors paint shop at Arlington, Texas, the complex conveyor system moving cars to the paint booths has been observed to mix up same color batches of cars coming from the body shop. At the paint booth, every …

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Use Of Wireless Signal Characteristics For Mobile Robotics Localization And Access Point Mapping, Joshua Davies Jan 2008

Use Of Wireless Signal Characteristics For Mobile Robotics Localization And Access Point Mapping, Joshua Davies

Computer Science and Engineering Theses - Archive

Mobile robotics is an interesting and challenging emerging field in computer science.To properly achieve true autonomy, a robot must be able to determine where it is in relationshipto a global frame of reference and it must be able to do so with a minimum of interaction fromhuman operators and impose as few constraints on its surroundings as possible. The uncertainnature of mobility and perception requires that advanced probabilistic inference techniques beapplied to minimize error. This work examines the applicability of radio-frequency signals to the mobile robotlocalization problem to localize quickly over a wide area. Particle filtering techniques areemployed to adjust …

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Thermal Characterization Of Dielectrically Isolated Bipolar Junction Transistor, Daewoo Kim Jan 2008

Thermal Characterization Of Dielectrically Isolated Bipolar Junction Transistor, Daewoo Kim

Electrical Engineering Dissertations - Archive

Since the integrated circuit (IC) was invented in 1960, the operating speed of semiconductor devices has steadily increased and the number of semiconductor devices in an IC chip has grown by a size reduction of the devices. This trend has lead to the rapid increase of power consumption and heat generation. As a result of this increase, thermal characterization of semiconductor devices has become more important.It is especially important to consider thermal characteristics of the dielectrically isolated complementary bipolar junction transistor (DIBJT) which offers many advantages. However, a major disadvantage of this device is an increase in self-heating. Because the …

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Towards An Implementation Of Avoip: Anonymous Voice-Over-Ip, Bikas Raj Gurung Jan 2008

Towards An Implementation Of Avoip: Anonymous Voice-Over-Ip, Bikas Raj Gurung

Computer Science and Engineering Theses - Archive

Voice over IP (VoIP) is one of the fastest growing telecommunicaiton market today. However with great popularity comes greater security risk. When we communicate over the Internet we expose our identity to all the prying eyes, even if we do not want to. Even though VoIP data can be secured by using encryption, sometimes the relationships between users can be sensitive. To provide stronger privacy for these users, we propose anonymous VoIP (aVoIP) - a means to secure user privacy in VoIP. The biggest challenge in introducing anonymity to VoIP system is in providing acceptable Quality of Service (QoS). Users …

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Temporal Potential Function Approach For Path Planning In Dynamic Environments, Vamsikrishna Gopikrishna Jan 2008

Temporal Potential Function Approach For Path Planning In Dynamic Environments, Vamsikrishna Gopikrishna

Computer Science and Engineering Theses - Archive

A Dynamic environment is one in which either the obstacles or the goal or both are in motion. In most of the current research, robots attempting to navigate in dynamic environments use reactive systems. Although reactive systems have the advantage of fast execution and low overheads, the tradeoff is in performance in terms of the path optimality. Often, the robot ends up tracking the goal, thus following the path taken by the goal, and deviates from this strategy only to avoid a collision with an obstacle it may encounter. In a path planner, the path from the start to the …

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Adapting Harmonic Function Path Planning: To Reflect User Motion Preferences, Giles John D'Silva Jan 2008

Adapting Harmonic Function Path Planning: To Reflect User Motion Preferences, Giles John D'Silva

Computer Science and Engineering Theses - Archive

Every human in the real world has a unique motion preference while moving to achieve a given task. These preferences could be expressed by moving in a straight line, following the wall along a corridor, avoiding sharp turns, preferring hard flat surfaces over damp uneven surfaces, choosing the shortest path to the goal or by giving a high priority towards safety by maintaining a definite distance from obstacles. To automatically incorporate user preferences into motion planning we could extract the trajectories taken by the user to achieve a task in a given local vironment and attempt to use them in …

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Cou-19-1, Ornitología Neotropical Jan 2008

Cou-19-1, Ornitología Neotropical

Ornitología Neotropical

No abstract provided.

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Cover, Ornitología Neotropical Jan 2008

Cover, Ornitología Neotropical

Ornitología Neotropical

No abstract provided.

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Cover, Ornitología Neotropical Jan 2008

Cover, Ornitología Neotropical

Ornitología Neotropical

No abstract provided.

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Algae Bloom In A Lake, David Sanabria Jan 2008

Algae Bloom In A Lake, David Sanabria

Undergraduate Journal of Mathematical Modeling: One + Two

The objective of this paper is to determine the likelihood of an algae bloom in a particular lake located in upstate New York. The growth of algae in this lake is caused by a high concentration of phosphorous that diffuses to the surface of the lake. Our calculations, based on Fick's Law, are used to create a mathematical model of the driving force of diffusion for phosphorous. Empirical observations are also used to predict whether the concentration of phosphorous will diffuse to the surface of this lake within a specified time and under specified conditions.

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Accent On Learning, 2008-2009, University Of South Florida Jan 2008

Accent On Learning, 2008-2009, University Of South Florida

USF Catalogs (Accent on Learning)

No abstract provided.

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Bulletin: General Catalog Issue 2008-2009, Portland State University Jan 2008

Bulletin: General Catalog Issue 2008-2009, Portland State University

Bulletin & Curriculum Change Documents

No abstract provided.

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Judicial Transparency In An Age Of Prediction, Adam M. Samaha Jan 2008

Judicial Transparency In An Age Of Prediction, Adam M. Samaha

Villanova Law Review (1956 - )

No abstract provided.

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Concerning The Financing Of Public Schools, And Making An Appropriation Therefor., Colorado General Assembly Jan 2008

Concerning The Financing Of Public Schools, And Making An Appropriation Therefor., Colorado General Assembly

Session Laws 2001-Present

No abstract provided.

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Concerning Changes To The Statutes Related To Higher Education, And, In Connection Therewith, Clarifying The Roles Of The Department Of Higher Education And The Colorado Commission On Higher Education, Consolidating Provisions Related To The Private Occupational School Division, And Repealing Obsolete Provisions., Colorado General Assembly Jan 2008

Concerning Changes To The Statutes Related To Higher Education, And, In Connection Therewith, Clarifying The Roles Of The Department Of Higher Education And The Colorado Commission On Higher Education, Consolidating Provisions Related To The Private Occupational School Division, And Repealing Obsolete Provisions., Colorado General Assembly

Session Laws 2001-Present

No abstract provided.

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Removing Long-Term Errors From The Avhrr Observation Based On Normalized Difference Vegetation Index (Ndvi), Md Zahidur Rahman, Leonid Roytman, Atiqur Rahman, Felix Kogan, Runa Jesmin Jan 2008

Removing Long-Term Errors From The Avhrr Observation Based On Normalized Difference Vegetation Index (Ndvi), Md Zahidur Rahman, Leonid Roytman, Atiqur Rahman, Felix Kogan, Runa Jesmin

Publications and Research

This paper investigates Normalized Difference Vegetation Index (NDVI) stability in the NOAA/NESDIS Global Vegetation Index (GVI) data during 1982-2003. Advanced Very High Resolution Radiometer (AVHRR) weekly data for the five NOAA afternoon satellites for the China dataset is studied, for it includes a wide variety of different ecosystems represented globally. It was found that data for the years 1988, 1992, 1993, 1994, 1995 and 2000 are not stable enough compared to other years because of satellite orbit drift, and AVHRR sensor degradation. It is assumed that data from NOAA-7 (1982, 1983), NOAA-9 (1985, 1986), NOAA-11 (1989, 1990), NOAA-14 (1996, 1997), …

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The Effectiveness Of Block Schedule In Middle School, Ginger L. Markham Jan 2008

The Effectiveness Of Block Schedule In Middle School, Ginger L. Markham

Perspectives In Learning

Block scheduling in one form or another seems to be highly effective when properly used. It invites depth in learning, inquiry based and student based learning, which corresponds with Georgia Performance Standards (GPS). The faculty and staff of Veterans Memorial Middle School are planning to meet the needs of the students by changing their teaching methods to support the GPS and alternating 4X4 block schedule. The author would recommend any middle school use a block schedule of some type in order to meet the needs of their school. Once the teachers buy into the concept, there is no limit to …

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