Coalition Formation Game for Cooperative Cognitive Radio Using Gibbs Sampling

This paper considers a cognitive radio network in which each secondary user selects a primary user to assist in order to get a chance of accessing the primary user channel. Thus, each group of secondary users assisting the same primary user forms a coaltion. Within each coalition, sequential relaying is employed, and a relay ordering algorithm is used to make use of the relays in an efficient manner. It is required then to find the optimal sets of secondary users assisting each primary user such that the sum of their rates is maximized. The problem is formulated as a coalition formation game, and a Gibbs Sampling based algorithm is used to find the optimal coalition structure.Comment: 7 pages, 2 figure

Object Oriented Implementation of the Parallel Toolkit Library

With manufacturing efficiencies and technological innovation the computing power of commodity machines has been increasing accompanied by decreasing costs. With the very favorable price/performance ratio the computing community has shifted from monolithic machines to networked machines. This has created the need for software to manage the parallelism of the network. One such work has been the Parallel Toolkit Library. The Parallel Toolkit Library provides support for common design functionalities used throughout parallel programs. This work extends the PTK C library for C++ parallel programs. The motivation for the current project stems from the need to let parallel programs reap the benefits of a library with an object oriented programming approach. This also fits well with the introduction of C++ bindings in MPI. The library has been structured on object-oriented concepts. The functionality of the PTK-C has been encapsulated into various classes. Individual functionalities have also been split into multiple classes leading to modularity and reusability of code. Template programming has been used to ensure type safety. The testing results are consistent with expectations in that the PTK-C++ is very much comparable to the PTK-C in terms of performance. In most cases, it would be more efficient to use the toolkit than to rewrite the code to recreate the efficiencies already present in the library

Easy-to-Use Augmented Reality in the Mobile Industry: an Internship Experience

This report details the work and research I have completed over the past few months with BUNDLAR. This company is a startup located in startup incubator 1871. BUNDLAR is currently developing their augmented reality mobile app that will launch in the near future. Over my time with them, I helped with market research. My research was focused on the Augmented Reality industry and performing competitive analysis on other AR companies. With this research, I was able to provide BUNDLAR with valuable recommendations and insights that helped shape their development around the target audience and industry. In addition, I also focused on performing quality assurance testing on a beta version of their mobile app. Because Iwas part of their target audience, I was able to provide valuable feedback on my user experience and report any problems and difficulties I experienced. Through my internship, I wanted to help BUNDLAR with releasing their easy-to-use AR platform. In this report, I will focus on my experience, business project, and key learnings.https://digitalcommons.imsa.edu/intern_reports_2020/1006/thumbnail.jp

Electromagnetic Wave-Matter Interactions in Complex Opto-Electronic Materials and Devices

This dissertation explores the fundamentals of light-matter interaction towards applications in the field of Opto-electronic and plasmonic devices. In its core, this dissertation attempts and succeeds in the the modeling of light-matter interactions, which is of high importance for better understanding the rich physics underlying the dynamics of electromagnetic field interactions with charged particles. Here, we have developed a self-consistent multi-physics model of electromagnetism, semiconductor physics and thermal effects which can be readily applied to the field of plasmotronics and Selective Laser Melting (SLM). Plasmotronics; a sub-field of photonics has experienced a renaissance in recent years by providing a large variety of new physical effects and applications. Most importantly, plasmotronics promises devices with ultra-small footprints and ultrafast operating speeds with lower energy consumption compared to conventional electronics. One of the primary objectives of this dissertation is to present an optoelectronic switch termed as Surface Plasmon Polariton Diode (SPPD) for functional plasmonic circuits based on active control of Surface Plasmon Polaritons (SPPs) at degenerate PN+-junction interfaces. In this context, the operational characteristics of the proposed plasmonic device are studied by the self-consistent multi-physics model that couples the electromagnetic, thermal and IV characteristics of the device. The SPPD uses heavily doped PN+-junction where SPPs propagate at the interface between N and P-doped layer and can be switched by an external voltage. Here, we explore the features of SPPD using three different semiconductor materials; GaAs, Silicon and Indium Gallium Arsenide (In0.53Ga0.47As). When compared to Si and GaAs, the In0.53Ga0.47As provides higher optical confinement, reduced system size and faster operation. For this reason, in our dissertation (In0.53Ga0.47As) is identified as the best semiconductor material for the practical implementation of the optoelectronic switch providing high optical confinement, reduced system size, and fast operation. The optimal device is shown to operate at signal modulation surpassing -100 dB and switching rates up to 50 GHz, thus potentially providing a new pathway toward bridging the gap between electronic and photonic devices. Also, the proposed optoelectronic switch is compatible with the current CMOS semiconductor fabrication techniques and could lead to nanoscale semiconductor-based optoelectronics. Furthermore, we have extended the concept of the above optoelectronic switch to design and study a new type of all-optical switch, referred to as Surface Plasmon Polariton Diode (thermal) (SPPDt). The SPPDt operation is governed by a unique optical nonlinearity that exists only for surface electromagnetic waves, i.e. SPPs, propagating at highly doped semiconductor junction interfaces. This dissertation will address the design and characterization of the SPPDt and will bring new insights into the underlying thermo optic nonlinearity. The gained understanding will be applied to design practically feasible devices including logic gates which can bridge the temporal and spatial gap between electronics and optics by providing high switching rates and signal input/output (I/O) power modulation. Enhanced light-matter interactions have further been explored and extended towards tailoring plasmonic resonances due to laser interactions with metal powder beds pertaining to Selective Laser Melting (SLM) processes. This is done by adapting the self consistent model developed for the plasmonic device to better understand the complex electrodynamic and thermodynamic processes involved in SLM. The SLM is an advanced rapid prototyping or additive manufacturing technology that uses high power density laser to fabricate metal/alloy components with minimal geometric constraints. The fabrication process is multi-physics in nature and its study requires the development of complex simulation tools. In this dissertation, for the first time, the electromagnetic interactions with dense powder beds are investigated under full-wave formalism. Localized gap and surface plasmon polariton resonance effects are identified as possible mechanisms toward improved absorption in small and medium-size titanium powder beds. Furthermore, observed near homogeneous temperature distributions across the metal powders indicates fast thermalization processes and allows for the development of simple analytical models to describe the dynamic interplay of laser facilitated Joule heating and effects of radiation and thermal conduction. The Explicit description is provided for important SLM process parameters such as critical laser power density, saturation temperature, and time to melt. Specific guidelines are presented for improved energy efficiency and optimization of the SLM process deposition rates

Pharmacokinetic Evaluation of a Novel Compound, Sn79, a Putative Sigma-2 Receptor Antagonist, By Intravenous and Oral Administration in Rats

Considering the alarming rates at which substance drug abuse, especially cocaine, is increasing in today\u27s society, there is a lot of impetus on the development of medications that can effectively help alleviate its toxicity and addiction. The affinity of cocaine to sigma receptors (sigma-1 and sigma-2) rendered the hypothesis that blocking sigma receptors could be a possible mechanism to attenuate cocaine-induced toxicity and addiction. In this view, SN79, a synthetic compound with selectivity to both sigma-1 and sigma-2 receptors garnered our attraction for its use as an antagonist. This dissertation encompasses detailed investigation of SN79 from drug discovery and development perspective. Development and validation of a bio-analytical method using ultra performance liquid chromatography-mass spectrophotometry to selectively separate and identify SN79 in biological matrix was a crucial part of this project. Determination of various physicochemical parameters including aqueous solubility, chemical stability, Log P and pKa etc are presented. A number of in vitro tests necessary for predicting the compound\u27s profile in the body were also performed. Single dose pharmacokinetic studies were conducted in fasted and fed state rats that help determine the disposition of SN79 in vivo

Electromagnetic Wave-Matter Interactions in Complex Optoelectronic Materials and Devices

Understanding the intricate physics of light-matter interactions is of high importance for the development of contemporary optoelectronic technologies. We have developed a multi-physics model which couples electromagnetism, semiconductor physics and thermal effects for applications in the fields of plasmotronics and Selective Laser Melting (SLM). A device architecture based on an InGaAs degenerate PN+-junction is shown to operate at signal modulation surpassing -100dB and switching rates up to 50GHz, thus providing a new pathway toward bridging the gap between electronic and photonic devices. Furthermore, the developed self-consistent model is adapted for studies of the complex electrodynamic and thermodynamic processes involved in SLM. The results provide new insights into the dynamic interplay between laser facilitated joule heating, radiation and thermal conduction; this under the full-wave formalism. Description is provided for important SLM process parameters such as critical laser power density, saturation temperature, and time to melt. Specific guidelines are presented for improved energy efficiency and optimization of the SLM process deposition rates

Predicting How People Vote From How They Tweet

In 2016 Donald Trump stunned the nation and not a single pollster predicted the outcome. For the last few decades, pollsters have relied on phone banking as their main source of information. There is reason to believe that this method does not present the complete picture it once did due to several factors--less landline usage, a younger and more active electorate, and the rise of social media. Social media specifically has grown in prominence and become a forum for political debate. This project quantitatively analyzes political twitter data and leverages machine learning techniques such as Naive-Bayes to model election results. Early results are promising, and a true evaluation of the model will come from testing in future elections

Socioeconomic characteristics of cancer mortality in the United States of America: a spatial data mining approach

Cancer is the second leading cause of death in the United States of America. Though it is generally known that cancer is influenced by environment, its relation to socioeconomic conditions is still widely debated. This research analyzed the spatial distribution of cancer mortalities of breast, colorectal, lung, and prostate, and their associated socioeconomic characteristics using association rule mining technique. The mortality patterns were analyzed at the county and health service area levels that corresponded to the years between 1999 – 2002 and 1988 – 1992, respectively. Distinct socioeconomic characteristics of cancer mortality were revealed by the association rule mining technique. The counties that had very high rates of breast cancer mortality also had very low percent of whites who walked to work; very high rates of colorectal cancer mortality was associated with very low percentage of foreign born population; very high rates of lung cancer mortality was associated with very low percent of whites who walked to work; and counties that had very high prostate cancer mortality rates had a very low percentage of their residents born in the west. The cancer mortality and socioeconomic variables were discretized using equal interval, natural breaks, and quantile discretization methods to analyze the impact discretization techniques have on the cancer mortality and socioeconomic patterns obtained using association rule mining. The three discretization techniques produced patterns that involved different rates of cancer mortality and socioeconomic characteristics. Results of this analysis showed that a 5-class interval natural breaks discretization technique achieved the highest discretization accuracy, while the equal interval method produced association rules that had the highest support value. The research also analyzed the effect of scale on the patterns produced by the association rule technique. At the county level breast and lung cancers associated with mode of transportation to work, whereas colorectal and prostate cancers associated with place of birth. At the health service area level, the association rule with the highest support value among the breast-, colorectal-, and prostate-cancer mortality rates involved a household family characteristics, whereas high lung cancer mortality rates were associated with low educational attainment