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Description
Breast microcalcifications are a potential indicator of cancerous tumors. Current visualization methods are either uncomfortable or impractical. Impedance measurement studies have been performed, but not in a clinical setting due to a low sensitivity and specificity. We are hoping to overcome this challenge with the development of a highly accurate impedance probe on a biopsy needle. With this technique, microcalcifications and the surrounding tissue could be differentiated in an efficient and comfortable manner than current techniques for biopsy procedures. We have developed and tested a functioning prototype for a biopsy needle using bioimpedance sensors to detect microcalcifications in the human body. In the final prototype a waveform generator sends a sin wave at a relatively low frequency(<1KHz) into the pre-amplifier, which both stabilizes and amplifies the signal. A modified howland bridge is then used to achieve a steady AC current through the electrodes. The voltage difference across the electrodes is then used to calculate the impedance being experienced between the electrodes. In our testing, the microcalcifications we are looking for have a noticeably higher impedance than the surrounding breast tissue, this spike in impedance is used to signal the presence of the calcifications, which are then sampled for examination by radiology.
ContributorsWen, Robert Bobby (Co-author) / Grula, Adam (Co-author) / Vergara, Marvin (Co-author) / Ramkumar, Shreya (Co-author) / Kozicki, Michael (Thesis director) / Ranjani, Kumaran (Committee member) / School of Molecular Sciences (Contributor) / Electrical Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Leveraging Machine Learning and Wireless Sensing for Robot Localization - Location Variance Analysis
Description
Object localization is used to determine the location of a device, an important aspect of applications ranging from autonomous driving to augmented reality. Commonly-used localization techniques include global positioning systems (GPS), simultaneous localization and mapping (SLAM), and positional tracking, but all of these methodologies have drawbacks, especially in high traffic indoor or urban environments. Using recent improvements in the field of machine learning, this project proposes a new method of localization using networks with several wireless transceivers and implemented without heavy computational loads or high costs. This project aims to build a proof-of-concept prototype and demonstrate that the proposed technique is feasible and accurate.
Modern communication networks heavily depend upon an estimate of the communication channel, which represents the distortions that a transmitted signal takes as it moves towards a receiver. A channel can become quite complicated due to signal reflections, delays, and other undesirable effects and, as a result, varies significantly with each different location. This localization system seeks to take advantage of this distinctness by feeding channel information into a machine learning algorithm, which will be trained to associate channels with their respective locations. A device in need of localization would then only need to calculate a channel estimate and pose it to this algorithm to obtain its location.
As an additional step, the effect of location noise is investigated in this report. Once the localization system described above demonstrates promising results, the team demonstrates that the system is robust to noise on its location labels. In doing so, the team demonstrates that this system could be implemented in a continued learning environment, in which some user agents report their estimated (noisy) location over a wireless communication network, such that the model can be implemented in an environment without extensive data collection prior to release.
Modern communication networks heavily depend upon an estimate of the communication channel, which represents the distortions that a transmitted signal takes as it moves towards a receiver. A channel can become quite complicated due to signal reflections, delays, and other undesirable effects and, as a result, varies significantly with each different location. This localization system seeks to take advantage of this distinctness by feeding channel information into a machine learning algorithm, which will be trained to associate channels with their respective locations. A device in need of localization would then only need to calculate a channel estimate and pose it to this algorithm to obtain its location.
As an additional step, the effect of location noise is investigated in this report. Once the localization system described above demonstrates promising results, the team demonstrates that the system is robust to noise on its location labels. In doing so, the team demonstrates that this system could be implemented in a continued learning environment, in which some user agents report their estimated (noisy) location over a wireless communication network, such that the model can be implemented in an environment without extensive data collection prior to release.
ContributorsChang, Roger (Co-author) / Kann, Trevor (Co-author) / Alkhateeb, Ahmed (Thesis director) / Bliss, Daniel (Committee member) / Electrical Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
At present, the vast majority of human subjects with neurological disease are still diagnosed through in-person assessments and qualitative analysis of patient data. In this paper, we propose to use Topological Data Analysis (TDA) together with machine learning tools to automate the process of Parkinson’s disease classification and severity assessment. An automated, stable, and accurate method to evaluate Parkinson’s would be significant in streamlining diagnoses of patients and providing families more time for corrective measures. We propose a methodology which incorporates TDA into analyzing Parkinson’s disease postural shifts data through the representation of persistence images. Studying the topology of a system has proven to be invariant to small changes in data and has been shown to perform well in discrimination tasks. The contributions of the paper are twofold. We propose a method to 1) classify healthy patients from those afflicted by disease and 2) diagnose the severity of disease. We explore the use of the proposed method in an application involving a Parkinson’s disease dataset comprised of healthy-elderly, healthy-young and Parkinson’s disease patients.
ContributorsRahman, Farhan Nadir (Co-author) / Nawar, Afra (Co-author) / Turaga, Pavan (Thesis director) / Krishnamurthi, Narayanan (Committee member) / Electrical Engineering Program (Contributor) / Computer Science and Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
Buck converters are a class of switched-mode power converters often used to step down DC input voltages to a lower DC output voltage. These converters naturally produce a current and voltage ripple at their output due to their switching action. Traditional methods of reducing this ripple have involved adding large discrete inductors and capacitors to filter the ripple, but large discrete components cannot be integrated onto chips. As an alternative to using passive filtering components, this project investigates the use of active ripple cancellation to reduce the peak output ripple. Hysteretic controlled buck converters were chosen for their simplicity of design and fast transient response. The proposed cancellation circuits sense the output ripple of the buck converter and inject an equal ripple exactly out of phase with the sensed ripple. Both current-mode and voltage-mode feedback loops are simulated, and the effectiveness of each cancellation circuit is examined. Results show that integrated active ripple cancellation circuits offer a promising substitute for large discrete filters.
ContributorsWang, Ziyan (Author) / Bakkaloglu, Bertan (Thesis director) / Kitchen, Jennifer (Committee member) / Electrical Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2017-12
Description
This thesis will examine the recruitment process of educated millennials coming from four-year institutions to their first job out of college. When referring to millennials throughout my research, I am specifically focusing on current college graduates in order to better relate to my own experiences as a soon-to-be-graduate seeking a job. I will examine the various recruiting techniques, i.e. channels to connect with graduates, and the hiring and interview process as a whole. This thesis will also discuss the challenges and differences of recruiting millennials versus other generations. It will also discuss the latest trends in college and early talent recruiting. In order to do this, I conducted a number of in-depth interviews with recruiters and hiring managers from various companies that recruit heavily from Arizona State University (ASU), in order to determine what these companies have done to be successful among young college graduates. I aimed to identify the specific techniques that these companies use to connect with recent college graduates, what skills these firms are looking for, and what the hiring process looks like for new millennial employees. I also conducted an extensive online literature search about recruiting educated millennials in the workforce, and I used that information as a basis to form my interview questions. The interviews were meant to confirm or deny that research, but the interviewees also revealed many new trends and insights. I hope that this information will be beneficial not only to college seniors seeking first-time employment, but also to other companies who feel that they are struggling to capture young talent.
ContributorsCapra, Alexandria Luccia (Author) / Kalika, Dale (Thesis director) / Eaton, Kathryn (Committee member) / W. P. Carey School of Business (Contributor) / Department of Marketing (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
ASU's international student population has been growing exponentially in the last few years. Specifically, the fastest growing group has been international students from China. However, many of these students are arriving with inaccurate expectations of life at an American university. Furthermore, prospective students in China that have a desire to attend school in the U.S. are struggling to find a university that is affordable and respected. There is a huge opportunity for ASU to reach this market of students and increase their enrollment of international Chinese students. Our project aimed to create advertisements of ASU that target international Chinese students and their parents. The purpose of our project is to provide inspiration that ASU can utilize to create a professional marketing campaign to target this population of potential students.
ContributorsKagiyama, Kristen (Co-author) / Le, Alethea (Co-author) / Chien, Hsui Fen (Thesis director) / Chau, Angie (Committee member) / W. P. Carey School of Business (Contributor) / Department of Marketing (Contributor) / Department of Supply Chain Management (Contributor) / School of International Letters and Cultures (Contributor) / School of Sustainability (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Fringe: Abstract Fringe is a feature length screenplay and a work of original science fiction. The story takes place in the future, on a planet far from Earth but it is told from the human perspective and is meant to draw into question many issues present in society today: prejudice, hatred, multiculturalism, war, and social division. The screenplay seeks to pose an allegorical relationship between the humanity living on the planet, and the enemies they face, and the present day conflict between America and the Middle East or ISIS. The story follows Miles as he is forced to ally with his sworn enemy, the Lue, and learn to fight together to save his world from destruction. Miles begins the film bitter, resentful, and filled with prejudice towards his foes, much like a majority of Americans today. Instead of focussing on that conflict though, my story unites these two bitter enemies and asks them to put aside their violent and hateful pasts to fight a new, more powerful foe together. As the events unfold my characters learn that their enemies can be just like them and that they have something valuable to offer their world. My screenplay is about finding commonality with the enemy, on both sides of a conflict. By the end of my tale, Miles learns that there is good to be found in the world, even in his sworn enemies, if he looks close enough. It may seem like an archetypal plot on the surface but I worked hard to create a world that has not been seen in film before, an original science fiction universe that can bring these issues into the light and entertain an audience while doing so. I feel that my screenplay does just that, offering entertainment with and edge of social commentary, and stays true to the science fiction form.
ContributorsTrcic, Colton Walker (Author) / Maday, Gregory (Thesis director) / Bernstein, Gregory (Committee member) / WPC Graduate Programs (Contributor) / W. P. Carey School of Business (Contributor) / School of Film, Dance and Theatre (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
The January 12, 2010 Haiti earthquake, which hit Port-au-Prince in the late afternoon, was the cause of over 220,000 deaths and $8 billion in damages \u2014 roughly 120% of national GDP at the time. A Mw 7.5 earthquake struck rural Guatemala in the early morning in 1976 and caused 23,000-25,000 deaths, three times as many injuries, and roughly $1.1 billion in damages, which accounted for approximately 30% of Guatemala's GDP. The earthquake which hit just outside of Christchurch, New Zealand early in the morning on September 4, 2010 had a magnitude of 7.1 and caused just two injuries, no deaths, and roughly 7.2 billion USD in damages (5% of GDP). These three earthquakes, all with magnitudes over 7 on the Richter scale, caused extremely varied amounts of economic damage for these three countries. This thesis aims to identify a possible explanation as to why this was the case and suggest ways in which to improve disaster risk management going forward.
ContributorsHeuermann, Jamie Lynne (Author) / Schoellman, Todd (Thesis director) / Mendez, Jose (Committee member) / Department of Supply Chain Management (Contributor) / Department of Economics (Contributor) / W. P. Carey School of Business (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Traditional educational infrastructures and their corresponding architectures have degenerated to work in opposition to today's scholastic objectives. In consideration of the necessity of formal education and academic success in modern society, a re-imagination of the ideal educational model and its architectural equivalent is long overdue. Fortunately, the constituents of a successful instructional method exist just outside our windows. This thesis, completed in conjunction with the ADE422 architectural studio, seeks to identify the qualities of a new educational paradigm and its architectural manifestation through an exploration of nature and biophilic design. Architectural Studio IV was challenged to develop a new academic model and corresponding architectural integration for the Herberger Young Scholars Academy, an educational institution for exceptionally gifted junior high and high school students, located on the West Campus of Arizona State University. A commencing investigation of pre-established educational methods and practices evaluated compulsory academic values, concepts, theories, and principles. External examination of scientific studies and literature regarding the functions of nature within a scholastic setting assisted in the process of developing a novel educational paradigm. A study of game play and its relation to the learning process also proved integral to the development of a new archetype. A hypothesis was developed, asserting that a nature-centric educational model was ideal. Architectural case studies were assessed to determine applicable qualities for a new nature-architecture integration. An architectural manifestation was tested within the program of the Herberger Young Scholars Academy and through the ideal functions of nature within an academic context.
ContributorsTate, Caroline Elizabeth (Author) / Underwood, Max (Thesis director) / Hejduk, Renata (Committee member) / De Jarnett, Mitchell (Committee member) / The Design School (Contributor) / W. P. Carey School of Business (Contributor) / School of Sustainability (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
The vastly growing field of supercomputing is in dire need of a new measurement system to optimize JMRAM (Josephson junction magnetoresistive random access memory) devices. To effectively measure these devices, an ultra-low-noise, low cost cryogenic dipping probe with a dynamic voltage range is required. This dipping probe has been designed by ASU with <100 nVp-p noise, <10 nV offsets, 10 pV to 16 mV voltage range, and negligible thermoelectric drift. There is currently no other research group or company that can currently match both these low noise levels and wide voltage range. Two different dipping probes can be created with these specifications: one for high-use applications and one for low-use applications. The only difference between these probes is the outer shell; the high-use application probe has a shell made of G-10 fiberglass for a higher price, and the low-use application probe has a shell made of AISI 310 steel for a lower price. Both types of probes can be assembled in less than 8 hours for less than $2,500, requiring only soldering expertise. The low cost and short time to create these probes makes wide profit margins possible. The market for these cryogenic dipping probes is currently untapped, as most research groups and companies that use these probes build their own, which allows for rapid business growth. These potential consumers can be easily reached by marketing these probes at superconducting conferences. After several years of selling >50 probes, mass production can easily become possible by hiring several technicians, and still maintaining wide profit margins.
ContributorsHudson, Brooke Ashley (Author) / Adams, James (Thesis director) / Anwar, Shahriar (Committee member) / Materials Science and Engineering Program (Contributor) / W. P. Carey School of Business (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05