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- Helical Propagation (3)
- Bandwidth Multiplier (2)
- Fiber optic channel (2)
- Optical Communication (2)
- Adaptive optics (1)
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- Agent systems (1)
- Attenuation (1)
- Autocorrelation (1)
- Beam Profile (1)
- Block-matching (1)
- Crisis management (1)
- Deconvolution (1)
- Denoising (1)
- Dispersion (1)
- EM Waveguide Model (1)
- Electromagnetic Propagation (1)
- Extended expansion (1)
- Horizontal path imaging (1)
- Image processing (1)
- Image reconstruction (1)
- Increased efficiency (1)
- Intensity-dependent noise (1)
- Medical imagery (1)
- Multiplexing (1)
- Optical Multiplexing; Bandwidth Enhancement; CAD Model; Fiber Taper Technique; Fiber Beam Profile. (1)
- Optical communication (1)
- Pulse Spreading (1)
- Rotary engine (1)
- Skew Rays (1)
- Soft computing (1)
Articles 1 - 11 of 11
Full-Text Articles in Engineering
Turbulence Measurement With Coherent Doppler Sonar, Jeremy Dillon
Turbulence Measurement With Coherent Doppler Sonar, Jeremy Dillon
Link Foundation Ocean Engineering and Instrumentation Fellowship Reports
The ocean has been described as Earth's "fi nal frontier" in a vision statement on ocean exploration (National Oceanic and Atmospheric Administration, 2000). The search for new insight is motivated by the fact that our environmental and economic security depends critically on the ocean and the freshwater bodies that drain into it. As the vast majority of the ocean is unknown and unexplored, there is great potential for scientifi c discovery beneath the sea surface (McNutt, 2002). The development of remote and in situ sensors forms a cornerstone of this vision for exploring ocean dynamics at new scales.
Cad Simulated And Experimental Beam Profile Analysis Of Single-Mode Tapered Fibers For Optical Bandwidth Enhancement Applications, Syed H. Murshid, Raka Biswas, Abhijit Chakravarty
Cad Simulated And Experimental Beam Profile Analysis Of Single-Mode Tapered Fibers For Optical Bandwidth Enhancement Applications, Syed H. Murshid, Raka Biswas, Abhijit Chakravarty
Electrical Engineering and Computer Science Faculty Publications
Most developments in data transfer techniques are incremental by nature and the goal of increasing total capacity in optical communications and networking requires new concepts for basic transmission media. The transmission data rates can only be enhanced by introducing new modulation and multiplexing techniques. In this paper different single mode tapered fiber waveguides are used to design a Spatial Multiplexer Unit (SMU) for a novel optical fiber multiplexing technique called the Spatial Domain Multiplexing (SDM) that allows co-propagation of two or more channels of exactly same wavelength without interfering with each other. This paper also presents a CAD model for …
Novel Wavelength Diversity Technique For High-Speed Atmospheric Turbulence Compensation, William W. Arrasmith, Sean F. Sullivan
Novel Wavelength Diversity Technique For High-Speed Atmospheric Turbulence Compensation, William W. Arrasmith, Sean F. Sullivan
Electrical Engineering and Computer Science Faculty Publications
The defense, intelligence, and homeland security communities are driving a need for software dominant, real-time or near-real time atmospheric turbulence compensated imagery. The development of parallel processing capabilities are finding application in diverse areas including image processing, target tracking, pattern recognition, and image fusion to name a few. A novel approach to the computationally intensive case of software dominant optical and near infrared imaging through atmospheric turbulence is addressed in this paper. Previously, the somewhat conventional wavelength diversity method has been used to compensate for atmospheric turbulence with great success. We apply a new correlation based approach to the wavelength …
Sdm Propagation Model For Multiple Channels Using Ray Theory, Syed H. Murshid, Ebad Zahir, Abhijit Chakravarty
Sdm Propagation Model For Multiple Channels Using Ray Theory, Syed H. Murshid, Ebad Zahir, Abhijit Chakravarty
Electrical Engineering and Computer Science Faculty Publications
Spatial Domain Multiplexing (SDM) is a novel optical fiber multiplexing technique where multiple channels of the same wavelength are launched at specific angles inside a standard step index multimode carrier fiber. These channels are confined to specific locations inside the fiber and they do not interfere with each other while traversing the length of the fiber. Spatial filtering techniques are employed at the output end to separate, route and process the individual channels. These skew ray channels inside the SDM system follow a helical trajectory along the fiber. The screen projection of the skew rays resembles a circular polygon. A …
Denoising Of X-Ray Imagery With Spatially-Varying Estimates Of Noise Variance, Samuel Peter Kozaitis
Denoising Of X-Ray Imagery With Spatially-Varying Estimates Of Noise Variance, Samuel Peter Kozaitis
Electrical Engineering and Computer Science Faculty Publications
We described a way to use a block-matching 3-D denoising algorithm to reduce noise in x-ray imagery. We first filtered an image multiple times using different estimates of the noise variance. From a simple estimate of the denoised image, we then estimated the noise variance at each pixel of the image. Using this approach, we obtained improved results when compared to using a single value of estimate for the noise variance. Even a small number of quantization levels of the estimates of the noise showed improved results.
Sdm Propagation Model For Multiple Channels Using Electromagnetic Theory And Vortex Analysis, Syed H. Murshid, Ebad Zahir, Raka Biswas, Abhijit Chakravarty
Sdm Propagation Model For Multiple Channels Using Electromagnetic Theory And Vortex Analysis, Syed H. Murshid, Ebad Zahir, Raka Biswas, Abhijit Chakravarty
Electrical Engineering and Computer Science Faculty Publications
Spatial Domain Multiplexing (SDM) is a novel technique in optical fiber communications. Single mode fibers are used to launch Gaussian beams of the same wavelength into a multimode step index fiber at specific angles. Based on the launch angle, the channel follows a helical path. The helical trajectory is explained with the help of vortex theory. The electromagnetic wave based vortex formation and propagation is mathematically modeled for multiple channels and the results are compared against experimental and simulated data. The modeled output intensity is analyzed to show a relationship between launch angle and the electric field intensity.
Comparison Of Experimental And Mathematical Models Of Attenuation And Dispersion For Co-Propagating Helical Channels Of Same Wavelength In Optical Fibers, Syed H. Murshid, Abhijit Chakravarty
Comparison Of Experimental And Mathematical Models Of Attenuation And Dispersion For Co-Propagating Helical Channels Of Same Wavelength In Optical Fibers, Syed H. Murshid, Abhijit Chakravarty
Electrical Engineering and Computer Science Faculty Publications
Spatial reuse of optical frequencies in optical fibers is possible through a novel Spatial Domain Multiplexing (SDM) technique that enables simultaneous propagation of two or more spatially multiplexed channels of exactly the same wavelength by confining them to unique spatial locations inside the fiber. Spatial filtering techniques are employed at the output end to separate the individual optical channels. The SDM channels follow helical path inside the carrier fiber and do not interfere with each other. This paper presents electromagnetic wave based model to analyze two such co-propagating SDM channels and then compares the model predictions to experimental data. The …
Simulation And Thermodynamic Analysis Of Extended Expansion On A Concept Rotary Engine Including Its Effects On Fuel Efficiency, Denis Allemant Andre, Matthew James Jensen, Gerald Micklow, James Brenner, Helgevon Helldorff
Simulation And Thermodynamic Analysis Of Extended Expansion On A Concept Rotary Engine Including Its Effects On Fuel Efficiency, Denis Allemant Andre, Matthew James Jensen, Gerald Micklow, James Brenner, Helgevon Helldorff
Mechanical and Civil Engineering Faculty Publications
This paper describes a novel method for extended expansion in a rotary combustion engine running ordinary gasoline. The engine consists of a toroidal-shaped piston that rotates around a drum to expand and evacuate the hot gas. There are several problems with today’s internal combustion (IC) engines. Current IC engines do not always have the necessary internal volume to extract the maximum work possible, and since the whole process of compression, combustion, and expansion happen within the same space, excess heat builds up and increases emissions of nitric oxides and nitrogen dioxide. The proposed solution is to redesign the IC engine …
Link Foundation 2008‐2010 Energy Fellowship Report, Vanessa Schweizer
Link Foundation 2008‐2010 Energy Fellowship Report, Vanessa Schweizer
Link Foundation Energy Fellowship Reports
I completed my PhD in Engineering and Public Policy at Carnegie Mellon University in May of 2010. My dissertation, entitled Developing Useful Long-term Energy Projections in the Face of Climate Change, seeks to identify methods that may calibrate expert judgments for anticipating long--‐term outcomes for energy demand and related greenhouse gas emissions that may not be obvious. The motivation for this research is to move beyond the false dichotomy that currently exists in traditional scenario analysis regarding questions of likelihood. Scenario exercises that aim to explore multiple visions of the future insist that judgments about the likelihood of each alternative …
Investigation And Modeling Of Ice Fracture In Cold Ocean Engineering Applications, Rocky S. Taylor
Investigation And Modeling Of Ice Fracture In Cold Ocean Engineering Applications, Rocky S. Taylor
Link Foundation Ocean Engineering and Instrumentation Fellowship Reports
Ice conditions present a significant challenge in the design of ships and structures for the development of offshore energy resources in cold ocean environments. Many regions throughout the world including Alaska, Canada, Russia, Norway, Kazakhstan and China are developing offshore energy resources in ice-prone environments. The growth and stability of the global economy is closely linked to that of our energy supply, and offshore industrial activity in Northern regions has increased significantly in recent years. One of the most significant engineering challenges when designing structures for ice environments is the estimation of design ice loads. The design load scenario for …
A Crisis Management Approach To Mission Survivability In Computational Multi-Agent Systems, Marco Carvalho, Aleksander Byrski, Marek Kisiel-Dorohinicki
A Crisis Management Approach To Mission Survivability In Computational Multi-Agent Systems, Marco Carvalho, Aleksander Byrski, Marek Kisiel-Dorohinicki
Electrical Engineering and Computer Science Faculty Publications
In this paper we present a biologically-inspired approach for mission survivability (consideredas the capability of fulfilling a task such as computation) that allows the system to be aware ofthe possible threats or crises that may arise. This approach uses the notion of resources usedby living organisms to control their populations.We present the concept of energetic selectionin agent-based evolutionary systems as well as the means to manipulate the configuration ofthe computation according to the crises or user’s specific demands.