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2012

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Articles 11251 - 11280 of 12196

Full-Text Articles in Physical Sciences and Mathematics

First Year Morphological Evolution Of An Artificial Berm At Fort Myers Beach, Florida, Katherine Brutsche, Ping Wang Jan 2012

First Year Morphological Evolution Of An Artificial Berm At Fort Myers Beach, Florida, Katherine Brutsche, Ping Wang

Geology Faculty Publications

This Coastal and Hydraulics Engineering Technical Note (CHETN) documents the sediment characteristics and first year morphological evolution of an artificial berm placed just offshore in Fort Myers Beach, Florida, based on a series of field data collection periods during the first year after the berm construction.

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Geology Of National Parks Modules For The Spreadsheets Across The Curriculum Library, H. L. Vacher, Thomas C. Juster, Judy Mcllrath, Mark Rains Jan 2012

Geology Of National Parks Modules For The Spreadsheets Across The Curriculum Library, H. L. Vacher, Thomas C. Juster, Judy Mcllrath, Mark Rains

Geology Faculty Publications

No abstract provided.

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Progress Towards Heterocycles As Inhibitors Of Plasminogen Activator Inhibitor-1, Gregory Alan Abernathy Jan 2012

Progress Towards Heterocycles As Inhibitors Of Plasminogen Activator Inhibitor-1, Gregory Alan Abernathy

Master's Theses and Doctoral Dissertations

No abstract provided.

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The Synthesis Of Amphiphilic Diblock Copolymers: An Investigation Into The Formation Of Micelles As A Function Of Hydrophobic Block Length, Kevin S. Kawchak Jan 2012

The Synthesis Of Amphiphilic Diblock Copolymers: An Investigation Into The Formation Of Micelles As A Function Of Hydrophobic Block Length, Kevin S. Kawchak

Master's Theses and Doctoral Dissertations

Acrylate-based amphiphilic diblock copolymers show great potential for anti-cancer drug transport due to their ability to aggregate into protective core-shell micelles. Using RAFT polymerization, copolymers containing poly(acrylic acid) and poly(methyl acrylate) blocks were made with high monomer conversion and narrow distributions of molecular weight for eventual use in medicinal applications. Based on previous findings of copolymers with low weight hydrophobic blocks failing to micellize, it was hypothesized that increasing the poly(methyl acrylate) block length would allow for micelle formation. 1H-NMR experiments conducted in the presence of an aqueous solution yielded diminished and broadened resonances of the lengthened hydrophobic block, which …

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Synthesis And Purification Of Potential Antimicrobial Peptides, Christopher Ryan Snyder Jan 2012

Synthesis And Purification Of Potential Antimicrobial Peptides, Christopher Ryan Snyder

Master's Theses and Doctoral Dissertations

No abstract provided.

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Development Techniques For Android Platform Mobile Device Application, Ivan Njunjic Jan 2012

Development Techniques For Android Platform Mobile Device Application, Ivan Njunjic

Master's Theses and Doctoral Dissertations

This thesis focuses on Android application development techniques needed to implement a mobile application portal that consists of features used at Eastern Michigan University. Since there is not a single source available to developers that explains such techniques, this thesis represents a unique manual for such development. Based on the similarity of features, mainly in terms of data nature and access, five techniques are defined in a step-by-step procedural manner. This is accomplished by outlining the development techniques and presenting them “in action” with coding examples from a fully developed demo application. As a result, the demo application demonstrates functional …

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Assessing Effectiveness Of Concept Map As Instructional Tool In High School Biology, Ritchie Adlaon Jan 2012

Assessing Effectiveness Of Concept Map As Instructional Tool In High School Biology, Ritchie Adlaon

LSU Master's Theses

This thesis emphasizes on an alternate instructional tool called “Concept Map”. The goal of this study was to determine the effectiveness of using concept maps in improving the science achievement of 10th -grade students and compare it with a traditional approach for a Biology unit. Furthermore, the interaction of the student’s concept mapping ability and their learning gains was investigated. Both the control and the experimental groups were required to take a pre test before instruction and a posttest at the end of three weeks. The test consisting of 31 questions was used to assess learning gains on a Biology …

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Magnetostratigraphy Susceptibility Correlations For The Guadalupian-Lopingian Boundary And The Placement Of The North American Ochoan Series: Texas (Usa) And South China, Matthew Allan Clark Jan 2012

Magnetostratigraphy Susceptibility Correlations For The Guadalupian-Lopingian Boundary And The Placement Of The North American Ochoan Series: Texas (Usa) And South China, Matthew Allan Clark

LSU Master's Theses

Stratigraphic studies have emphasized the use of multiple, geochemical and geochemical proxies to investigate critical geologic boundaries, events and their correlation throughout the entire Phanerozoic. In this study, an emerging geophysical proxy, mass-specific, low-field magnetic susceptibility (χ) is used to investigate the global correlation of the Guadalupian-Lopingian (G-L) boundary, to better resolve and supplement biostratigraphic correlations, including inferred G-L boundary sections defining the base of the North American Ochoan Series. The North American Ochoan Series of West Texas, defined lithostratigraphically by the contact between the Bell Canyon and Castile Formations, represents a unique and well-studied sequence in the Delaware Basin, …

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Artificial Oyster Reefs In The Northern Gulf Of Mexico: Management, Material, And Faunal Effects, Jessica Nicole Furlong Jan 2012

Artificial Oyster Reefs In The Northern Gulf Of Mexico: Management, Material, And Faunal Effects, Jessica Nicole Furlong

LSU Master's Theses

Artificial oyster reefs seek to restore reef ecosystem services, such as water filtration, shoreline protection, and habitat for nekton. This study established three objectives to address the dispersed nature of artificial reef information in the Gulf of Mexico (GoM) and lack of post-construction monitoring assessments. First, to document the extent of activities in the GoM, we developed a database of all inshore artificial oyster reefs created for restoration purposes. Of the 422 reefs in the resultant database, a third or less provided records of entities involved (27%), restoration goals (24%), area (20%), monitoring efforts (15%), relief (9%), and costs (8%). …

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Using Generalized Estimating Equations To Analyze Repeated Measures Binary Data From The Young Adolescent Crowd Study, Lauren Ashley Beacham Jan 2012

Using Generalized Estimating Equations To Analyze Repeated Measures Binary Data From The Young Adolescent Crowd Study, Lauren Ashley Beacham

LSU Master's Theses

The young adolescent crowd study (YACS) was conducted in order to look at the influence of various factors on use of controlled substances by middle school students. The contributing factors investigated were demographics (gender and race), self-esteem in different modalities such as school or athletic performance, and the peer group students belong to. Each student has a binary response for whether they have used alcohol, marijuana or cigarettes which was recorded in both seventh and eighth grade. Since the data has a binary repeated measures response, generalized estimating equations (GEE) in a logistic regression setting is a good way to …

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Measuring City Commitment To Climate Change Mitigation, Kelsey Wefer Clinton Jan 2012

Measuring City Commitment To Climate Change Mitigation, Kelsey Wefer Clinton

LSU Master's Theses

An increasing number of cities are focusing on sustainability and climate change mitigation by joining groups such the International Council for Local Environmental Initiatives (ICLEI). ICLEI uses a five-step milestone process to help cities achieve their mitigation goals. These milestones include conducting a greenhouse gas inventory, setting reduction targets, creating a Climate Action Plan, and implementing and monitoring that plan. Prior studies have examined factors that may influence a city’s decision to join ICLEI, but few have looked at how committed the cities are to sustainability and to ICLEI itself after joining the organization. The purpose of this study is …

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Spatial Ability And Achievement In High School Physics, Michael Shawn Liner Jan 2012

Spatial Ability And Achievement In High School Physics, Michael Shawn Liner

LSU Master's Theses

This study investigates the relationship between a student’s spatial abilities and their success in high school physics. First, I investigate whether the success of students in high school physics class correlates with their spatial abilities before taking the class. Second, I investigate whether taking high school physics has an effect on student’s spatial abilities. No direct intervention was given to any of the students. Three instruments were administered to determine the student’s spatial abilities, The Perspective Taking/Spatial Orientation Test (Hegarty & Waller, 2004), The Mental Rotation Test (Peters & Laeng, 1995), and The Paper Folding Test (Ekstrom, French, Harmon, & …

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Composition And Physiological Characteristics Of The University Lake Ecosystem Phytoplankton Community: Impacts Of Seasonal And Episodic Events, Brianne Elizabeth Norris Jan 2012

Composition And Physiological Characteristics Of The University Lake Ecosystem Phytoplankton Community: Impacts Of Seasonal And Episodic Events, Brianne Elizabeth Norris

LSU Master's Theses

This research determined the changes in phytoplankton community composition in a shallow subtropical lake, influenced by urban surroundings. Specifically this research focused on the effects of seasonal progression and episodic events on the changing inorganic nutrient dynamics and the effects those dynamics had on the phytoplankton community composition and productivity. This research quantified gross primary production and respiration to determine if seasonality or episodic events were acting as forcing functions of the phytoplankton community composition. Water samples were collected weekly at three sites on the lake’s perimeter, as well as following episodic events, to monitor nitrate (NO3), phosphate (PO4-3), ammonium …

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Movements And Habitat Use Of Southeastern Blue Sucker Cycleptus Merdionalis In The Lower Pearl River, Devon Charles Oliver Jan 2012

Movements And Habitat Use Of Southeastern Blue Sucker Cycleptus Merdionalis In The Lower Pearl River, Devon Charles Oliver

LSU Master's Theses

Riverine fisheries management programs often do not focus on non-sport and non-commercial fishes, such as catostomids, yet many suckers have become threatened or endangered throughout river systems in the United States because of habitat alterations. In the Pearl River, sedimentation, dam construction, and other hydrologic modifications have negatively impacted habitats used by southeastern blue suckers Cycleptus meridionalis, a species of concern in both Louisiana and Mississippi. The principal objective of this project was to investigate habitat use of likely historically abundant southeastern blue suckers in the lower Pearl River. During electrofishing surveys in 2010 and 2011, we observed no southeastern …

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Mapping Of The Oil Window In The Eagle Ford Shale Play Of Southwest Texas Using Thermal Modeling And Log Overlay Analysis, Austin Pourciau Cardneaux Jan 2012

Mapping Of The Oil Window In The Eagle Ford Shale Play Of Southwest Texas Using Thermal Modeling And Log Overlay Analysis, Austin Pourciau Cardneaux

LSU Master's Theses

The Eagle Ford formation in South Texas has been an established hydrocarbon play since 2008. The Eagle Ford is considered an unconventional resource because it is a source, reservoir, and seal. Hydraulic fracturing and horizontal drilling have enabled this play. As drilling and production continue the limits of this play are being defined. The area between dry gas and wet gas/condensate has been known for some time since the initial production started in dry gas and moved up-dip. After the oil window was discovered, the contact between wet gas/condensate started to become more defined. Now companies are beginning to delineate …

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Evaluation Of Growth Rates And Establishment Patterns Of Water-Elm (Planera Aquatica) And Baldcypress (Taxodium Distichum) In Response To Hydrologic And Climatic Conditions At Catahoula Lake, Louisiana, Sanjeev Joshi Jan 2012

Evaluation Of Growth Rates And Establishment Patterns Of Water-Elm (Planera Aquatica) And Baldcypress (Taxodium Distichum) In Response To Hydrologic And Climatic Conditions At Catahoula Lake, Louisiana, Sanjeev Joshi

LSU Master's Theses

Hydrologic alterations frequently lead to vegetation changes in floodplain ecosystems. In Louisiana, there has been an expansion of water-elm (Planera aquatica) and to a lesser extent baldcypress (Taxodium distichum) at Catahoula Lake, a Ramsar Wetland of International Importance. Water-elm and baldcypress both are flood tolerant species; baldcypress growth is known to be influenced by hydrologic conditions more than climate. The expansion of these woody trees has reduced herbaceous vegetation valuable for waterfowl. In this study, I tested two hypotheses that establishment of water-elm trees into the lake increased after the construction of water control structures in the nearby Black River …

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A Treatment Planning Comparison Of Dual-Arc Vmat Vs. Helical Tomotherapy For Post-Mastectomy Radiotherapy, Geoffrey Paul Nichols Jan 2012

A Treatment Planning Comparison Of Dual-Arc Vmat Vs. Helical Tomotherapy For Post-Mastectomy Radiotherapy, Geoffrey Paul Nichols

LSU Master's Theses

Purpose: To investigate the feasibility of volumetric modulated arc therapy (VMAT) for post-mastectomy radiotherapy (PMRT) and to compare dual-arc VMAT treatment plans to helical tomotherapy (HT) plans on the basis of dosimetric quality, radiobiological calculations and delivery efficiency. Methods: Dual-arc VMAT and HT treatment plans were created for fifteen patients previously treated at our clinic. Planning target volumes (PTV) included the chest wall and regional lymph nodes. The following metrics were used to compare treatment plans for each patient: dose homogeneity index (DHI) and conformity index (CI); coverage of the PTV; dose to organs at risk (OAR); tumor control probability …

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Impact Of Teaching Style On Student Learning Of Evolution, Laurie Font Jan 2012

Impact Of Teaching Style On Student Learning Of Evolution, Laurie Font

LSU Master's Theses

Natural selection is a topic that is laden with misconceptions. These misconceptions are often not addressed, and students can leave a biology classroom with the same incorrect ideas that they entered with. These misconceptions can be identified and addressed by using the Concept Inventory of Natural Selection (CINS). Furthermore, by teaching using methods that encourage hands-on, inquiry based techniques, students are more apt to reconcile these misconceptions and have a deeper understanding of the natural selection process. The goal of my research was to show a positive correlation between reduction in student misconceptions about natural selection and inquiry based activities. …

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Focus Question Effect On Dynamic Thinking In A Concept Map, Blake John Orgeron Jan 2012

Focus Question Effect On Dynamic Thinking In A Concept Map, Blake John Orgeron

LSU Master's Theses

A concept map is an educational tool designed to help identify, represent, and categorize relationships between different ideas relating to an overall concept. Relationships or transitions between the ideas are created by students and can either be static or dynamic. Static transitions help to describe, define, and organize knowledge for a given domain. Dynamic transitions show how a change in quantity, quality, or state in one concept causes change in quantity, quality, or state in the other concept. The focus question of the map directs student input of the concepts and ultimately determines what types of transitions are used. The …

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The Effects Of Carbon On Nitrogen Transformations In Restored Wetland And Wastewater Soils, Jared M. Theriot Jan 2012

The Effects Of Carbon On Nitrogen Transformations In Restored Wetland And Wastewater Soils, Jared M. Theriot

LSU Master's Theses

Since the industrialization of the Haber-Bosch process in the 1940’s, anthropogenic activity has nearly doubled the Earth’s nitrogen fixation. Furthermore, nitrate has become the number one groundwater contaminant in the United States and has harmful effects such as eutrophication, algal blooms, and pollution of drinking water. Soils from two sites influenced by high nitrate loading were examined to determine their biogeochemical integrity. First, the Loosahatchie Bar, located northwest of Memphis, Tennessee, is influenced by excess surface water nitrate loading by the Mississippi River. The Loosahatchie Bar is a newly restored wetland that now has similar hydrologic influence to an upstream …

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Pretesting In Science: Effect On Unit Test Scores, Mary Catherine Johnson Jan 2012

Pretesting In Science: Effect On Unit Test Scores, Mary Catherine Johnson

LSU Master's Theses

ABSTRACT This study examines the effect that pretesting has on unit test scores in a high school Biology I classroom. The experimental classes were given a pretest before four units of curriculum and then taught the concepts of these units with a traditional lecture based methodology. Their unit test scores were compared to a control class that did not take pretests before the units. In addition, the End of Course (EOC) test scores of the control and experimental classes were compared to determine if pretesting improved transfer of knowledge to a different type of test. Pretesting did not cause a …

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Mathematical Modeling In The High School Classroom, Selena Oswalt Jan 2012

Mathematical Modeling In The High School Classroom, Selena Oswalt

LSU Master's Theses

Mathematical modeling is the procedure whereby students apply mathematical concepts learned in class to new and unfamiliar situations. A modeling task is a mathematically-rich problem that engages students in mathematical thinking, drawing upon their previously learned knowledge and supporting their understanding of the mathematical concepts currently being covered. Modeling requires students to assign meaning to the mathematical concepts and to extend the concepts beyond rote learning. In order for students to be successful in a classroom that is centered around the idea of mathematical modeling, the students must be taught how to collaborate with other students, persevere through challenging problems, …

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Nitrogen Biogeochemistry In A Restored Mississippi River Delta: A Modeling Approach, Benjamin Lee Branoff Jan 2012

Nitrogen Biogeochemistry In A Restored Mississippi River Delta: A Modeling Approach, Benjamin Lee Branoff

LSU Master's Theses

There is evidence that significant reductions (about 50%) in surface water nitrate concentrations within coastal deltaic wetlands receiving diverted Mississippi River water can be contributed to denitrification. Yet there is also contrasting evidence that other processes could be responsible for this nitrate reduction. As Louisiana plans the implementation of major Mississippi River sediment diversions, a thorough understanding of nitrogen dynamics is necessary to reduce risks of coastal eutrophication and offshore hypoxia. A mechanistic numerical computer model has been developed to simulate nitrogen biogeochemistry within the wetlands of the prograding Wax Lake Delta. This model is calibrated to observed fluxes within …

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Performance Analysis Of Two Priority Queuing Systems In Tandem, Faouzi Kamoun Jan 2012

Performance Analysis Of Two Priority Queuing Systems In Tandem, Faouzi Kamoun

All Works

In this paper, we consider a tandem of two head-of-line (HOL) non-preemptive priority queuing systems, each with a single server and a deterministic service-time. Two classes of traffic are considered, namely high priority and low priority traffic. By means of a generating function approach, we present a technique to derive closed-form expressions for the mean buffer occupancy at each node and mean delay. Finally, we illustrate our solution technique with some numerical examples, whereby we illustrate the starvation impact of the HOL priority scheduling discipline on the performance of the low-priority traffic stream. Our research highlights the important fact that …

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A Novel Method Of Studying Ion Formation And Fragmentation Using A Modified Time-Of-Flight Mass Spectrometer, David S. Ames Jan 2012

A Novel Method Of Studying Ion Formation And Fragmentation Using A Modified Time-Of-Flight Mass Spectrometer, David S. Ames

Dissertations and Theses @ UNI

Laser desorption has been an important tool in mass spectrometry. It has been known that an order of magnitude more neutrals than ions are produced during laser desorption. A Time-Of-Flight Mass Spectrometer with an infinitely adjustable acceleration region was constructed to map the population distribution of neutral ion precursors and metastable ions in the flight tube. Desorption was performed by using a nitrogen UV laser at 337 nm. Experiments conclude that the majority of post-source ionization of neutrals occurs approximately 2.5 cm from the sample-laser interface. The intensity of ions tapers rapidly out to 6.0 cm, however ions were detected …

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Crisis Response Information Networks, Shan L. Pan, Gary Pan, Dorothy Leidner Jan 2012

Crisis Response Information Networks, Shan L. Pan, Gary Pan, Dorothy Leidner

Research Collection School Of Accountancy

In the past two decades, organizational scholars have focused significant attention on how organizations manage crises. While most of these studies concentrate on crisis prevention, there is a growing emphasis on crisis response. Because information that is critical to crisis response may become outdated as crisis conditions change, crisis response research recognizes that the management of information flows and networks is critical to crisis response. Yet despite its importance, little is known about the various types of crisis information networks and the role of IT in enabling these information networks. Employing concepts from information flow and social network theories, this …

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First Remote Sensing Observations Of Trifluoromethane (Hfc-23) In The Upper Troposphere And Lower Stratosphere, Jeremy J. Harrison, Christopher D. Boone, Alexander T. Brown, Nicholas D. C. Allen, Geoffrey C. Toon, Peter F. Bernath Jan 2012

First Remote Sensing Observations Of Trifluoromethane (Hfc-23) In The Upper Troposphere And Lower Stratosphere, Jeremy J. Harrison, Christopher D. Boone, Alexander T. Brown, Nicholas D. C. Allen, Geoffrey C. Toon, Peter F. Bernath

Chemistry & Biochemistry Faculty Publications

This work reports the first remote sensing measurements of atmospheric HFC-23 (CHF3) using solar occultation measurements made by the Atmospheric Chemistry Experiment Fourier transform spectrometer (ACE-FTS) and the Jet Propulsion Laboratory Mark IV (MkIV) balloon interferometer. A total of 8809 ACE occultations measured between 2004 and 2010 have been processed, along with 24 MkIV occultations measured between 1989 and 2007. ACE data (yearly averages over the 10-25 km altitude range) in the tropics/subtropics (40°S-40°N) reveal a trend of 4.0 ± 1.6% per year in the growth of HFC-23 for 2004-2009 (or 3.9 ± 1.2% per year for 2004-2010), …

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Structural And Optical Studies On La Doped Cds Nanocrystalline Films, Kusumanjali Dehmukh, Mimi Mukherjee, Shashi Bhushan Jan 2012

Structural And Optical Studies On La Doped Cds Nanocrystalline Films, Kusumanjali Dehmukh, Mimi Mukherjee, Shashi Bhushan

Turkish Journal of Physics

This paper reports the synthesis of pure and lanthanum (La) doped nanocrystalline CdS semiconducting films on the glass substrate by means of chemical bath deposition (CBD), with Cd(CH_3COO)_2 as Cadmium (Cd) ion source, (NH_2)_2CS as sulphur (S) ion source and Thioglycerol as capping agent. Long, rod like structures is observed in SEM micrographs of the films. XRD studies show the existence of both hexagonal and cubic phases. Increase in FWHM is observed for smaller particle due to nanocrystalline effect. UV-VIS absorption studies show shift of absorption edge towards lower wavelength side. Corresponding change in band gap energy results in shift …

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Specific Heat Of Ytterbium Iron Garnet Yb_3fe_5o_{12} At Low Temperatures, Abdelmalek Boumali, Oumhani Derar Jan 2012

Specific Heat Of Ytterbium Iron Garnet Yb_3fe_5o_{12} At Low Temperatures, Abdelmalek Boumali, Oumhani Derar

Turkish Journal of Physics

The state of the Yb^{3+} ion of the ytterbium iron garnet (Yb_3Fe_5O_{12}) is suitable for the development of theoretical models with rather good approximations. Using the theory of two-level paramagnetic ions, the total and magnetic specific heat at low temperatures has been calculated. The influence of tensors g and G on the specific heat of YbIG has been examined. A comparison has been made of our results and those obtained with a model based on of the approximation of Weiss Molecular-Field (WMF) and experimental data.

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Characterization Of Analog Modulation Of Algaas Lasers And The Induced Intensity Noise, Moustafa Ahmed, Nour Zaki El-Sayed, Hameeda Ibrahim, Kamal Abdelhady Jan 2012

Characterization Of Analog Modulation Of Algaas Lasers And The Induced Intensity Noise, Moustafa Ahmed, Nour Zaki El-Sayed, Hameeda Ibrahim, Kamal Abdelhady

Turkish Journal of Physics

The dynamics of AlGaAs laser diodes under analog intensity modulation are characterized and the associated intensity noise is evaluated. The study is based on numerical solution of the stochastic rate equations of semiconductor lasers. Based on the shape of the modulated laser signal, the modulation dynamics are classified into eight distinct types. Four types are characterized by continuous periodic signals, and three types have periodic pulsing signals. These signals happen to have period doubling or superposed by sub-peaks from the relaxation oscillations of the laser. The last type is chaos, in which the signal is irregular and non-uniform. The noise …

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