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2010

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Do Karst Rivers “Deserve” Their Own Biotic Index? A Ten Years Study On Macrozoobenthos In Croatia, Biljana Rađa, Sanja Puljas Jan 2010

Do Karst Rivers “Deserve” Their Own Biotic Index? A Ten Years Study On Macrozoobenthos In Croatia, Biljana Rađa, Sanja Puljas

International Journal of Speleology

In this study we present the results of a ten year survey of the aquatic macroinvertebrate fauna along four karst rivers: Jadro, Žrnovnica, Grab and Ruda, all of them situated in the Middle Dalmatia region of Croatia, in an attempt to construct the Iliric Biotic Index, which will be more applicable for the water quality analysis than the most frequently applied biotic index in Croatia, the Italian Modification of Extended Biotic Index. The rivers geologically belong to the Dinaric karst, unique geological phenomena in Europe. Benthic macroinvertebrates were collected along each river at 15 sites by standard methods of sampling …

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Spatial Distribution Of Soda Straws Growth Rates Of The Coufin Cave (Vercors, France), Yves Perrette, Stéphane Jaillet Jan 2010

Spatial Distribution Of Soda Straws Growth Rates Of The Coufin Cave (Vercors, France), Yves Perrette, Stéphane Jaillet

International Journal of Speleology

The Choranche Cave system (Vercors, France) is an excellent locality for measuring the growth rates of large numbers soda straws. This is especially the case for the Coufin Cave, as enlargement of the cave entrance in 1875 led to a change in stalactite color from brown to white, thus providing a reliable chronomarker. The date of this brown-to-white calcite transition has been confirmed by lamina counting. We measured and georeferenced the growth-lengths of 306 soda straws in a 1m2 area of the roof of the Coufin Cave entrance chamber. Because of the very slow and sometimes inexistent water feeding …

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Karst Geology And Cave Fauna Of Austria: A Concise Review, Erhard Christian, Christoph Spötl Jan 2010

Karst Geology And Cave Fauna Of Austria: A Concise Review, Erhard Christian, Christoph Spötl

International Journal of Speleology

The state of cave research in Austria is outlined from the geological and zoological perspective. Geologic sections include the setting of karst regions, tectonic and palaeoclimatic control on karst, modern cave environments, and karst hydrology. A chapter on the development of Austrian biospeleology in the 20th century is followed by a survey of terrestrial underground habitats, biogeographic remarks, and an annotated selection of subterranean invertebrates.

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Optimal Integrator-Less Tracking Controller For Uncertain Systems, Anusha Mannava Jan 2010

Optimal Integrator-Less Tracking Controller For Uncertain Systems, Anusha Mannava

Masters Theses

"Tracking controllers are designed to drive the system on the desired trajectory with minimum error. In real life, all systems have uncertainties such as friction, modeling inaccuracies or damage that cause the performance to deviate from the ideal response. This research is aimed at addressing the tracking problem in the optimal context and a generalized method to handle the uncertainties is proposed. In the first paper, an optimal tracking controller without an integral component is formulated for a linear system. This design can handle time varying, non-zero references and effectively alleviates the risk of 'wind up'. A neural network based …

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Bayesian Approaches On Observational Before-After Highway Safety Analysis, Daxiao Liu Jan 2010

Bayesian Approaches On Observational Before-After Highway Safety Analysis, Daxiao Liu

Masters Theses

"Observational before-after evaluation of roadway safety treatments effect is a necessary and challenging study area for traffic safety engineers. In decades, empirical Bayesian approach has been widely adopted among researchers in this area. In this approach, the researcher combined before period observation data with a safety performance function estimated from similar groups to estimate the expected number of crashes that would have occurred in the after period without the treatment. Comparing this estimate with the number of crashes observed in the after period, the researcher evaluated the effectiveness of the treatment. This approach accounts for well-known regression-to-the-mean effects. However, as …

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Impact Of Management Status, Gender, And Level Of Project Involvement On Corporate Governance In A Role-Based Enterprise Portal Environment, Daniel Augusto Pereira Brás Sequeira Jan 2010

Impact Of Management Status, Gender, And Level Of Project Involvement On Corporate Governance In A Role-Based Enterprise Portal Environment, Daniel Augusto Pereira Brás Sequeira

Masters Theses

"The underlying objective of this research project is to investigate the impact of management status, gender, and level of project involvement on corporate governance in a role-based enterprise portal environment. This is achieved through a case study which included the development of a role-based enterprise portal site prototype assessed through surveys targeted at different stakeholders at the case company. Six hypotheses were formulated addressing the core research question. The outcomes of the hypotheses testing suggest employees' perceptions of role-based enterprise portal's effectiveness, usability, and corporate identity design are, in general, not influenced by the employees' management role, gender, and project …

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Characterizing Near-Field Circuit Board Radiation Using Crossed Electric And Magnetic Dipole Sources, Weiping He Jan 2010

Characterizing Near-Field Circuit Board Radiation Using Crossed Electric And Magnetic Dipole Sources, Weiping He

Masters Theses

"A method to analyze radiated emissions of electronic components/circuits is presented in this thesis. More specifically the purpose of this approach is to determine an equivalent source model to accurately represent the radiated emissions produced by the circuits and components. The proposed equivalent source model, which is able to predict both electric and magnetic fields at various distances from the device under test, consists of an array of both electric and magnetic dipoles. Each source point includes two electric dipoles orientated in x and y directions and two magnetic dipoles in x and y directions"--Abstract, page iii.

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Control And Applications Of Double Input Dc-Dc Power Electronic Converters, Venkata Anand Kishore Prabhala Jan 2010

Control And Applications Of Double Input Dc-Dc Power Electronic Converters, Venkata Anand Kishore Prabhala

Masters Theses

"Multi-input power electronic converters (MIPEC) are increasingly gaining interest in the fields of renewable energy systems and hybrid electric vehicles (HEV). The main advantage of MIPECs is their ability to interface several energy sources and storage devices using a single power conversion stage. Therefore, they provide simpler control and smaller parts count. In this thesis, various aspects of the utilization of double-input (DI) converters in solar and HEV applications are explored. For instance, a DI buckboost topology is proposed for a photovoltaic (PV)/battery energy system. The converter is controlled in a way that maximum power is drawn from the PV …

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Improving Resiliency Using Graph Based Evolutionary Algorithms, Jayakanth Jayachandran Jan 2010

Improving Resiliency Using Graph Based Evolutionary Algorithms, Jayakanth Jayachandran

Masters Theses

"Resiliency is an important characteristic of any system. It signifies the ability of a system to survive and recover from unprecedented disruptions. Various characteristics exist that indicate the level of resiliency in a system. One of these attributes is the adaptability of the system. This adaptability can be enhanced by redundancy present within the system. In the context of system design, redundancy can be achieved by having a diverse set of good designs for that particular system. Evolutionary algorithms are widely used in creating designs for engineering systems, as they perform well on discontinuous and/or high dimensional problems. One method …

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Signal Analysis For Multiple Target Materials Through Wavelet Transforms, Rajat Pashine Jan 2010

Signal Analysis For Multiple Target Materials Through Wavelet Transforms, Rajat Pashine

Masters Theses

"Signal identification based on different sensing systems like microwaves, infra-red, x-rays and terahertz waves is one of the classic problems in signal processing. Earlier methods had relied mainly on the amplitude spectrum obtained by these sensing techniques mainly due to non-availability of the phase information for the signals. Most of them are based on techniques like absorbance spectrum that requires a reference material's signal for the test material's identification. They are also sensitive to noise and highly dependent on the peak detection algorithms. Modern equipments with both amplitude and phase information provide an opportunity for time-domain signal based methods that …

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Fpga Implementation Of Pso Algorithm And Neural Networks, Parviz Palangpour Jan 2010

Fpga Implementation Of Pso Algorithm And Neural Networks, Parviz Palangpour

Masters Theses

"This thesis describes the Field Programmable Gate Array (FPGA) implementations of two powerful techniques of Computational Intelligence (CI), the Particle Swarm Optimization algorithm (PSO) and the Neural Network (NN). Particle Swarm Optimization (PSO) is a popular population-based optimization algorithm. While PSO has been shown to perform well in a large variety of problems, PSO is typically implemented in software. Population-based optimization algorithms such as PSO are well suited for execution in parallel stages. This allows PSO to be implemented directly in hardware and achieve much faster execution times than possible in software. In this thesis, a pipelined architecture for hardware …

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2-D Path Planning For Direct Laser Deposition Process, Swathi Routhu Jan 2010

2-D Path Planning For Direct Laser Deposition Process, Swathi Routhu

Masters Theses

"The zigzag and offset path have been the two most popular path patterns for tool movement in machining process. Different from the traditional machining processes, the quality of parts produced by the metal deposition process is much more dependent upon the choice of deposition paths. Due to the nature of the metal deposition processes, various tool path patterns not only change the efficiency but also affect the deposition height, a critical quality for metal deposition process. This thesis presents the research conducted on calculating zigzag pattern to improve efficiency by minimizing the idle path. The deposition height is highly dependent …

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Closed-Form Solutions To Discrete-Time Portfolio Optimization Problems, Mathias Christian Goggel Jan 2010

Closed-Form Solutions To Discrete-Time Portfolio Optimization Problems, Mathias Christian Goggel

Masters Theses

"In this work, we study some discrete time portfolio optimization problems. After a brief introduction of the corresponding continuous time models, we introduce the discrete time financial market model. The change in asset prices is modeled in contrast to the continuous time market by stochastic difference equations. We provide solutions for these stochastic difference equations. Then we introduce the discrete time risk-measure and the portfolio optimization problems. We provide closed form solutions to the discrete time problems. The main contribution of this thesis are the closed form solutions to the discrete time portfolio models. For simulation purposes the discrete time …

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Quantification Of Product Color Preference In A Utility Function, Hannah L. Turner Jan 2010

Quantification Of Product Color Preference In A Utility Function, Hannah L. Turner

Masters Theses

"Currently, many marketing and engineering tools exist to help a designer optimize quantitative attributes of a product, such as height, weight, volume, or cost. However, these methods cannot effectively take into consideration aesthetic attributes of a product, or any other attributes for which there is no understood functional relationship between the attribute's potential values and the consumer's preference. This research has begun the work of developing this necessary functional relationship for the aesthetic attribute of color and has created a methodology for further research. To do this, colors were represented by their red, green, and blue light components, and preference …

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Stable Isotopes Reveal A Consistent Consumer-Diet Relationship Across Hundreds Of Kilometres, Mathew A. Vanderklift, Thomas Wernberg Jan 2010

Stable Isotopes Reveal A Consistent Consumer-Diet Relationship Across Hundreds Of Kilometres, Mathew A. Vanderklift, Thomas Wernberg

Research outputs pre 2011

Characterising geographical variation in trophic interactions is an important step towards understanding the consequences of changes in food webs. We characterised geographical variation across ~1000 km in stable isotope values (δ15N and δ13C) of the widely distributed sea urchin Heliocidaris erythrogramma and macroalgae that are its potential food. Variation in δ15N of H. erythrogramma and macroalgae was typically greatest among locations separated by hundreds of km, while variation in δ13C was typically greatest among reefs separated by a few km. Geographical variation in δ15N and δ13C of H. erythrogramma was well-explained by variation in δ15N and δ13C of the kelp …

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Redtnet: A Network Model For Strategy Games, Philip Hingston, Mike Preuss, Daniel Spierling Jan 2010

Redtnet: A Network Model For Strategy Games, Philip Hingston, Mike Preuss, Daniel Spierling

Research outputs pre 2011

In this work, we develop a simple, graph-based framework, RedTNet, for computational modeling of strategy games and simulations. The framework applies the concept of red teaming as a means by which to explore alternative strategies. We show how the model supports computer-based red teaming in several applications: realtime strategy games and critical infrastructure protection, using an evolutionary algorithm to automatically detect good and often surprising strategies.

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Autonomous Bee Colony Optimization For Multi-Objective Function, F Zeng, James Decraene, Malcolm Low, Philip Hingston, C Wentong, Z Suiping, M Chandramohan Jan 2010

Autonomous Bee Colony Optimization For Multi-Objective Function, F Zeng, James Decraene, Malcolm Low, Philip Hingston, C Wentong, Z Suiping, M Chandramohan

Research outputs pre 2011

An Autonomous Bee Colony Optimization (A-BCO) algorithm for solving multi-objective numerical problems is proposed. In contrast with previous Bee Colony algorithms, A-BCO utilizes a diversity-based performance metric to dynamically assess the archive set. This assessment is employed to adapt the bee colony structures and flying patterns. This self-adaptation feature is introduced to optimize the balance between exploration and exploitation during the search process. Moreover, the total number of search iterations is also determined/optimized by A-BCO, according to user pre-specified conditions, during the search process. We evaluate A-BCO upon numerical benchmark problems and the experimental results demonstrate the effectiveness and robustness …

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A Novel Binarization Algorithm For Ballistics Imaging Systems, Zhihu Huang, Jinsong Leng Jan 2010

A Novel Binarization Algorithm For Ballistics Imaging Systems, Zhihu Huang, Jinsong Leng

Research outputs pre 2011

The identification of ballistics specimens from imaging systems is of paramount importance in criminal investigation. Binarization plays a key role in preprocess of recognizing cartridges in the ballistic imaging systems. Unfortunately, it is very difficult to get the satisfactory binary image using existing binary algorithms. In this paper, we utilize the global and local thresholds to enhance the image binarization. Importantly, we present a novel criterion for effectively detecting edges in the images. Comprehensive experiments have been conducted over sample ballistic images. The empirical results demonstrate the proposed method can provide a better solution than existing binary algorithms.

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Android Forensics: Simplifying Cell Phone Examinations, Jeff Lessard, Gary Kessler Jan 2010

Android Forensics: Simplifying Cell Phone Examinations, Jeff Lessard, Gary Kessler

Research outputs pre 2011

It is hardly appropriate to call the devices many use to receive the occasional phone call a telephone any more. The capability of these devices is growing, as is the number of people utilizing them. By the end of 2009, 46.3% of mobile phones in use in the United States were reported to be smart phones (AdMob, 2010). With the increased availability of these powerful devices, there is also a potential increase for criminals to use this technology as well. Criminals could use smart phones for a number of activities such as committing fraud over e-mail, harassment through text messages, …

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Wireless Acoustic Communications And Power Supply For In-Vivo Biomedical Devices, Graham Wild, Steven Hinckley Jan 2010

Wireless Acoustic Communications And Power Supply For In-Vivo Biomedical Devices, Graham Wild, Steven Hinckley

Research outputs pre 2011

Pacemakers are common biomedical devices used in the treatment of specific cardiovascular problems. Current research in biomedical engineering is investigating the use of so called brain pacemakers to regulate conditions such as Parkinson's and other neurological conditions. In this paper, we demonstrate the principle of acoustic communications and power harvesting, in vivo. The signals are intended to be used for fixed in vivo biomedical devices, such as pacemakers, were wired and wireless RF communications cannot be used. Results show the performance of the communications channel. The frequency response, transfer function and transient response (at resonance) of the communications channel were …

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Examining Pacing Profiles In Elite Female Road Cyclists Using Exposure Variation Analysis, Chris Abbiss, Leon Straker, Marc Quod, David Martin, Paul Laursen Jan 2010

Examining Pacing Profiles In Elite Female Road Cyclists Using Exposure Variation Analysis, Chris Abbiss, Leon Straker, Marc Quod, David Martin, Paul Laursen

Research outputs pre 2011

Objective In this study, the amplitude and time distribution of power output in a variety of competitive cycling events through the use of a new mathematical analysis was examined: exposure variation analysis (EVA). Design Descriptive field study. Setting Various professional road cycling events, including; a 5-day—eight-stage tour race, a 1-day World Cup event and the Australian National Individual Time Trial Championships. Participants 9 elite female cyclists (mean (SD), mass = 57.8 (3.4) kg, height = 167.3 (2.8) cm, Vo2peak = 63.2 (5.2) ml kg−1 min−1). Interventions None. Main outcome measurements The variation in power output and the quantification of the …

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A Novel Subspace Outlier Detection Approach In High Dimensional Data Sets, Jinsong Leng Jan 2010

A Novel Subspace Outlier Detection Approach In High Dimensional Data Sets, Jinsong Leng

Research outputs pre 2011

Many real applications are required to detect outliers in high dimensional data sets. The major difficulty of mining outliers lies on the fact that outliers are often embedded in subspaces. No efficient methods are available in general for subspace-based outlier detection. Most existing subspacebased outlier detection methods identify outliers by searching for abnormal sparse density units in subspaces. In this paper, we present a novel approach for finding outliers in the ‘interesting’ subspaces. The interesting subspaces are strongly correlated with `good' clusters. This approach aims to group the meaningful subspaces and then identify outliers in the projected subspaces. In doing …

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Light Reductions Drive Macroinvertebrate Changes In Amphibolis Griffithii Seagrass Habitat, Adam Gartner, Paul S. Lavery, Kathryn Mcmahon, Anne Brearley, Helen Barwick Jan 2010

Light Reductions Drive Macroinvertebrate Changes In Amphibolis Griffithii Seagrass Habitat, Adam Gartner, Paul S. Lavery, Kathryn Mcmahon, Anne Brearley, Helen Barwick

Research outputs pre 2011

Numerous anthropogenic activities can significantly reduce the amount of light reaching seagrass habitats. Typically these result in morphological and physiological changes to the plant and associated algal epiphytes. However, the flow-on effects to seagrass-dependent fauna induced by these disturbances has yet to be examined. This study investigated the effects of different light reduction intensity (high: ~92% reduction; moderate: ~84% reduction), duration (3, 6 and 9 mo) and timing (post-winter and post-summer) on the density and biomass of macroinvertebrate epifauna within an Amphibolis griffithii seagrass ecosystem (Western Australia). There were generally lower epifauna densities and biomass within shaded seagrass plots. When …

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Interrogation Of Water Catchment Data Sets Using Data Mining Techniques, Ajdin Sehovic, Leisa Armstrong, Dean Diepeveen Jan 2010

Interrogation Of Water Catchment Data Sets Using Data Mining Techniques, Ajdin Sehovic, Leisa Armstrong, Dean Diepeveen

Research outputs pre 2011

Current environmental challenges such as increasing dry land salinity, water logging, eutrophication and high nutrient runoff in south western regions of Western Australia (WA) may have both cultural and environmental implications in the near future. Advances in computing through the application of data mining ,and geographic information services provide the tools to conduct •studies that can indicate possible changes in these water catchment areas of WA. The research examines the existing spatial data mining techniques that can be used to interpret trends in WA water catchment land use. Large GIS data sets of the water catchments on Peel-Harvey region have …

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Caviar And The Australian Stock Markets : An Appetiser, David E. Allen, A. K. Singh Jan 2010

Caviar And The Australian Stock Markets : An Appetiser, David E. Allen, A. K. Singh

Research outputs pre 2011

Value-at-Risk (VaR) has become the universally accepted metric adopted internationally under the Basel Accords for banking industry internal control and for regulatory reporting. This has focused attention on methods of measuring, estimating and forecasting lower tail risk. One promising technique is Quantile Regression which holds the promise of efficiently calculating (VAR). To this end, Engle and Manganelli in (2004) developed their CAViaR model (Conditional Autoregressive Value at Risk). In this paper we apply their model to Australian Stock Market indices and a sample of stocks, and test the efficacy of four different specifications of the model in a set of …

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Official/ Unofficial: Information Management And Social Association, Kay Hearn Jan 2010

Official/ Unofficial: Information Management And Social Association, Kay Hearn

Research outputs pre 2011

This paper explores the debates around civil society and corporatism as ways of understanding changes in social association, including non-governmental organisations and protest groups, and information management in relation to the development of the Internet. Both concepts have been used to examine the changes that have taken place since the implementation of the Open Door Policy and more recently the development of the Internet, and have shed light on the way in which new forms of social association operate, and on their relationship to the government. However, both concepts tend to be deterministic and eductionist positions. Instead, I use a …

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Adaptive Optical Splitter Employing An Opto-Vlsi Processor And A 4-F Imaging System, Haithem Ab Mustafa, Feng Xiao, Kamal Alameh Jan 2010

Adaptive Optical Splitter Employing An Opto-Vlsi Processor And A 4-F Imaging System, Haithem Ab Mustafa, Feng Xiao, Kamal Alameh

Research outputs pre 2011

A novel adaptive optical splitter structure employing an Opto-VLSI processor and 4-f imaging system is proposed and experimentally demonstrated. By driving the Opto-VLSI processor with computer generated multicasting phase holograms, an input optical signal launched into an input optical fiber port can be split and coupled into many output optical fiber ports with arbitrary splitting ratios. A proof-of-principle 1 2 adaptive optical splitter structure driven by optimized multicasting phase holograms uploaded onto the Opto-VLSI processor is developed, demonstrating an arbitrary splitting ratio over a wavelength range exceeding 50 nm.

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How Do You Make Information Security User Friendly?, Andrew Jones Jan 2010

How Do You Make Information Security User Friendly?, Andrew Jones

Research outputs pre 2011

This article explores the past and the present situation, outlines a new approach, and presents conclusions.

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Ignorant Experts: Computer And Network Security Support From Internet Service Providers, Patryk Szewczyk, Craig Valli Jan 2010

Ignorant Experts: Computer And Network Security Support From Internet Service Providers, Patryk Szewczyk, Craig Valli

Research outputs pre 2011

The paper examines the advice and support provided by seven major Internet Service Providers in Australia through late 2009 and early 2010 in relation to computer and network security. Previous research has indicated that many end-users will attempt to utilise the support provided by Internet Service Providers as a simple and effective method by which to obtain key information in regards to computer security. This paper demonstrates that in many cases the individuals working at the help desk are either reluctant to provide IT security support or have insufficient skill to provide the correct information.

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Adiabatic Coherent Quantum Tunneling Of Ultracold Atoms Trapped In An Asymmetrical Two-Dimensional Magnetic Lattices, Ahmed Abdelrahman, Kamal Alameh, Peter Hannford Jan 2010

Adiabatic Coherent Quantum Tunneling Of Ultracold Atoms Trapped In An Asymmetrical Two-Dimensional Magnetic Lattices, Ahmed Abdelrahman, Kamal Alameh, Peter Hannford

Research outputs pre 2011

We propose a new method to realize a two-dimensional magnetic lattice, having two different configurations of asymmetric magnetic lattice, which exhibits magnetic band gap structure, and a symmetric magnetic lattice. We also describe the tunneling mechanisms of magnetically trapped ultracold atoms, prepared in a degenerate quantum gas such as Bose-Einstein Condensate (BEC). A coherent quantum tunneling of ultracold atoms between the sites of the asymmetrical magnetic lattice can be realized which induces the adiabatically controlled dc Josephson current. At critical phase transitions, namely at certain values of site phase difference and population fraction, a plasma oscillation can be observed in …

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