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Title: Evaluation and validation of soft robotic end effectors for produce harvesting
Creator: Dutcher, Zachary F.
Date: 2018
Collection: Electronic Theses & Dissertations
Description: Global population is expected to exceed 9 billion people by 2050 which will require a 70% increase in net global food production. 75% of global farm holdings are considered small at 2.5 acres or less. While contemporary industrial farming gains efficiency through increased mechanization, it comes with significant environmental costs. Industrial farming practices such as frequent tillage, monocropping and use of synthetic fertilizers, pesticides and herbicides are unsustainable practices that...
Show moreGlobal population is expected to exceed 9 billion people by 2050 which will require a 70% increase in net global food production. 75% of global farm holdings are considered small at 2.5 acres or less. While contemporary industrial farming gains efficiency through increased mechanization, it comes with significant environmental costs. Industrial farming practices such as frequent tillage, monocropping and use of synthetic fertilizers, pesticides and herbicides are unsustainable practices that will continue to degrade the surrounding ecosystem. Small scale farms present an opportunity to utilize regenerative farming practices; however, they are potentially challenging to scale up and expensive to automate with conventional automation solutions. In this thesis, soft robotic end effectors are explored as a potential means of harvesting on regenerative (as well as conventional) farms. Three end effector designs are testing for parameters including grasp variability, grasp effectiveness and real-world simulation on apple orchards at Michigan State University. Apple harvesting metrics including detachment force, diameter and weight have been collected for one hundred early harvest Spartan-Macintosh variety apples. Results of this evaluation show promise for the application of these low-cost technologies; however, much work is needed before a complete and viable soft robotic harvesting system is available.
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Title: Design, construction, & calibration of a sixty-inch integrating sphere photometer
Creator: Hedrich, Walter A.
Date: 1932
Collection: Electronic Theses & Dissertations

Title: The design and organisation features of two online courses : a case study of their emergence and evolution
Creator: Richards, Kari
Date: 2017
Collection: Electronic Theses & Dissertations
Description: This study reports the findings of a qualitative case study that examined how elements of design and organization were conceptualized and enacted in two graduate level online courses, and, how these conceptualizations and enactments evolved. Data was collected through interviews and ‘think-alouds’ with the course instructors and through screen captures of the course home pages. The Community of Inquiry Framework (CoI) (Garrison, Anderson, & Archer, 2000) was used as a lens to analyze the data...
Show moreThis study reports the findings of a qualitative case study that examined how elements of design and organization were conceptualized and enacted in two graduate level online courses, and, how these conceptualizations and enactments evolved. Data was collected through interviews and ‘think-alouds’ with the course instructors and through screen captures of the course home pages. The Community of Inquiry Framework (CoI) (Garrison, Anderson, & Archer, 2000) was used as a lens to analyze the data for the Design & Organization element of the framework’s concept of Teaching Presence. The analysis identified patterns in the five features of the Design & Organization element: Setting Curriculum, Designing Methods, Establishing Time Parameters, Utilizing the Medium, and Establishing Netiquette. The data shows variation in the way most of the features are conceptualized and enacted in the online courses, with some exceptions. These variations reflect the different experiences, expectations, and logic of the two instructors, while the exceptions reflect the influence of external norming agents such as the Learning Management System or institutional guidelines. The results indicate a wider range of possibilities in course design and organization than the CoI framework has been conceptualized to account for, which has implications for the various programs and institutions using the framework as an instrument for their evaluation of online courses.
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Title: Integration of planning, design, and construction to train 21st century urban professionals
Creator: Dalton, Robert
Date: 2016
Collection: Electronic Theses & Dissertations
Description: The built environment professions are struggling as budgets decrease and scope and importance increase. Attempting to save money, clients are turning to multidisciplinary offices for all-in-one service. Higher education can respond to these shifting trends by preparing the students for a growth mindset and openness to the ideas constructed by a team rather than an individual. Integrative learning may foster such minds. Integrative learning concerns the building of cognitive connections from...
Show moreThe built environment professions are struggling as budgets decrease and scope and importance increase. Attempting to save money, clients are turning to multidisciplinary offices for all-in-one service. Higher education can respond to these shifting trends by preparing the students for a growth mindset and openness to the ideas constructed by a team rather than an individual. Integrative learning may foster such minds. Integrative learning concerns the building of cognitive connections from one skill or piece of knowledge to the next. This study found cultural areas shared among professions as well as those distinct to one profession. These cultural attributes group into four categories: axiology, epistemology, methodology, and ontology. All professions rate learning (epistemology) the required skills best while they work in offices, rather than their time in higher education. Methodologies include the tasks accomplished to plan, design, and build a project and the tools used to do so. Each profession brings their own contributions to problem solving and uses varied software to accomplish their means. These contributions are highly related to the corresponding values (axiology), though mean ratings indicate a high value for a task even if it is not one’s own. The study concludes by assessing the products (ontology) that may be created by the professions most likely to work together. The teams coming together most often represent the professions of the exterior spaces, building and interior spaces, and the legal and real estate professions. Employers and educators alike may use this information to understand the differences among the professional cultures and how bridging these divides or allowing gaps to remain can impact the project delivery.
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Title: Enhancing item pool utilization when designing multistage computerized adaptive tests
Creator: Yang, Lihong
Date: 2016
Collection: Electronic Theses & Dissertations
Description: In recent years, the multistage adaptive test (MST) has gained increasing popularity in the field of educational measurement and operational testing. MST refers to a test in which pre-constructed sets of items are administered adaptively and are scored as a unit (Hendrickson, 2007). As a special case of Computerized Adaptive Testing (CAT), a MST program needs the following components: an item response theory (IRT) model or non-IRT-based alternatives; an item pool design; module assembly;...
Show moreIn recent years, the multistage adaptive test (MST) has gained increasing popularity in the field of educational measurement and operational testing. MST refers to a test in which pre-constructed sets of items are administered adaptively and are scored as a unit (Hendrickson, 2007). As a special case of Computerized Adaptive Testing (CAT), a MST program needs the following components: an item response theory (IRT) model or non-IRT-based alternatives; an item pool design; module assembly; ability estimation; routing algorithm; and scoring (Yan et al., 2014). A significant amount of research has been conducted on components like module assembly, ability estimation, routing and scoring, but few studies have addressed the component of item pool design. An item pool is defined as consisting of a maximal number of combinations of items that meet all content specifications for a test and provide sufficient item information for estimation at a series of ability levels (van der Linden et al., 2006). An item pool design is very important because any successful MST assembly is inseparable from an optimal item pool that provides sufficient and high-quality items (Luecht & Nungester, 1998). Reckase (2003, 2010) developed the p-optimality method to design optimal item pools using the unidimensional Rasch model in CAT, and it has been proved to be efficient for different item types and IRT models. The present study extended this method to MST context in supporting and developing different MST panel designs under different test configurations. The study compared the performance of the MST assembled under the most popularly studied panel designs in the literature, such as 1-2, 1-3, 1-2-2, and 1-2-3. A combination of short, medium and long tests with different routing test proportions were used to build up different tests. Using one of the most popularly investigated IRT models, the Rasch model, simulated optimal item pools were generated with and without practical constraints of exposure control. A total number of 72 optimal items pools were generated and the measurement accuracy was evaluated by an overall sample and conditional sample using various statistical measures. The p-optimality method was also applied in an operational MST licensure test to see if it is feasible in supporting test assembly and achieving sufficient measurement accuracy in practice. Results showed that the different MST panel designs achieved sufficient measurement accuracy by using the items from the optimal item pools built with the p-optimality method. The same was true with the operational item pool. Measurement accuracy was related to test length, but not so much to the routing test proportions. Exposure control affected the item pool size, but the distributions of the item parameters and item pool characteristics for all the MST panel designs were similar under the two conditions. The item pool sizes under the exposure control conditions were several times larger than those under no exposure control, depending on the types of MST panel designs and routing test proportions. The results from this study provide information for how to enhance item pool utilization when designing multistage computerized adaptive tests, facilitating the MST assembly process, and improving the scoring accuracy.
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Title: Design and evaluation of a health care needs assessment tool for adults with cerebral palsy and mental retardation
Creator: Clark, Nuala Catherine
Date: 1991
Collection: Electronic Theses & Dissertations

Title: Reliable 5G system design and networking
Creator: Liang, Yuan (Graduate of Michigan State University)
Date: 2019
Collection: Electronic Theses & Dissertations
Description: The upcoming fifth generation (5G) system is expected to support a variety of different devices and applications, such as ultra-reliable and low latency communications, Internet of Things (IoT) and mobile cloud computing. Reliable and effective communications lie in the core of the 5G system design. This dissertation is focused on the design and evaluation of robust 5G systems under both benign and malicious environments, with considerations on both the physical layer and higher layers. For...
Show moreThe upcoming fifth generation (5G) system is expected to support a variety of different devices and applications, such as ultra-reliable and low latency communications, Internet of Things (IoT) and mobile cloud computing. Reliable and effective communications lie in the core of the 5G system design. This dissertation is focused on the design and evaluation of robust 5G systems under both benign and malicious environments, with considerations on both the physical layer and higher layers. For the physical layer, we study secure and efficient 5G transceiver under hostile jamming. We propose a securely precoded OFDM (SP-OFDM) system for efficient and reliable transmission under disguised jamming, a serious threat to 5G, where the jammer intentionally confuses the receiver by mimicking the characteristics of the authorized signal, and causes complete communication failure. We bring off a dynamic constellation by introducing secure randomness between the legitimate transmitter and receiver, and hence break the symmetricity between the authorized signal and the disguised jamming. It is shown that due to the secure randomness shared between the authorized transmitter and receiver, SP-OFDM can achieve a positive channel capacity under disguised jamming. The robustness of the proposed SP-OFDM scheme under disguised jamming is demonstrated through both theoretic and numerical analyses. We further address the problem of finding the worst jamming distribution in terms of channel capacity for the SP-OFDM system. We consider a practical communication scenario, where the transmitting symbols are uniformly distributed over a discrete and finite alphabet, and the jamming interference is subject to an average power constraint, but may or may not have a peak power constraint. Using tools in functional analysis and complex analysis, first, we prove the existence and uniqueness of the worst jamming distribution. Second, by analyzing the Kuhn-Tucker conditions for the worst jamming, we prove that the worst jamming distribution is discrete in amplitude with a finite number of mass points. For the higher layers, we start with the modeling of 5G high-density heterogeneous networks. We investigate the effect of relay randomness on the end-to-end throughput in multi-hop wireless networks using stochastic geometry. We model the nodes as Poisson Point Processes and calculate the spatial average of the throughput over all potential geometrical patterns of the nodes. More specifically, for problem tractability, we first consider the simple nearest neighbor (NN) routing protocol, and analyze the end-to-end throughput so as to obtain a performance benchmark. Next, note that the ideal equal-distance routing is generally not realizable due to the randomness in relay distribution, we propose a quasi-equal-distance (QED) routing protocol. We derive the range for the optimal hop distance, and analyze the end-to-end throughput both with and without intra-route resource reuse. It is shown that the proposed QED routing protocol achieves a significant performance gain over NN routing. Finally, we consider the malicious link detection in multi-hop wireless sensor networks (WSNs), which is an important application of 5G multi-hop wireless networks. Existing work on malicious link detection generally requires that the detection process being performed at the intermediate nodes, leading to considerable overhead in system design, as well as unstable detection accuracy due to limited resources and the uncertainty in the loyalty of the intermediate nodes themselves. We propose an efficient and robust malicious link detection scheme by exploiting the statistics of packet delivery rates only at the base stations. More specifically, first, we present a secure packet transmission protocol to ensure that except the base stations, any intermediate nodes on the route cannot access the contents and routing paths of the packets. Second, we design a malicious link detection algorithm that can effectively detect the irregular dropout at every hop (or link) along the routing path with guaranteed false alarm rate and low miss detection rate.
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Title: Instrument automation and measurement data curation platform for enhancing research reproducibility and knowledge discovery
Creator: Gtat, Yousef
Date: 2019
Collection: Electronic Theses & Dissertations
Description: "Many applications demand the continued development of sensing systems that employ smart sensors, instrumentation circuits, and signal processing techniques to extract relevant information from real-world environments. In the engineering efforts to develop new sensors, tasks such as instrument automation, measurement process curation, real-time data acquisition, data analysis, and long-term tracking of inter-related datasets generate a significant volume and variety of information that is...
Show more"Many applications demand the continued development of sensing systems that employ smart sensors, instrumentation circuits, and signal processing techniques to extract relevant information from real-world environments. In the engineering efforts to develop new sensors, tasks such as instrument automation, measurement process curation, real-time data acquisition, data analysis, and long-term tracking of inter-related datasets generate a significant volume and variety of information that is challenging to organize, record, and analyze. Sensor development and characterization experiments can be laborious, prone to human error, difficult to repeat precisely, and can produce data that are challenging to interpret. Such issues highlight a need for a structured, automated approach to curate measurement processes and data acquisition. This thesis presents the first software platform for i) digitally designing measurement recipes, ii) remotely scheduling and monitoring experiment execution, iii) automatic data acquisition, iv) analyzing and storing results datasets, and v) linking the datasets with their prospective meta-datasets for deeper analysis and inspection. The proposed platform is flexible and capable of managing a large set of diverse instruments, measurement recipes and sensor datasets. By employing several design abstractions, it allows users to remotely design, schedule, monitor and execute measurement-based experiments while archiving results along with their information-rich metadata therefore preserving the provenance of the datasets. The platform enable precise timing control of instruments and stimulus signals along with long-term tracking of datasets eliminating manual errors and human omissions thus enhancing research reproducibility and promoting knowledge discovery methodologies."--Page ii.
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Title: Design of a centrifugal pump for liquid fuel pumping application
Creator: Cao, David Thiepxuan
Date: 2002
Collection: Electronic Theses & Dissertations

Title: SLEEP MANAGEMENT AS A COLLABORATIVE WORK FOR THE FAMILY : DESIGNING SLEEP MANAGEMENT SYSTEMS TO IMPROVE BEDTIME ROUTINE
Creator: Shin, Ji Youn
Date: 2022
Collection: Electronic Theses & Dissertations
Description: Sleep is a vital health issue. In families with young children, sleep problems can influence the physical, emotional, and behavioral health of all family members. Previous studies have investigated sleep as an individual activity, rarely considering the interconnected aspects of sleep among family members. To understand the social aspects of family sleep, this dissertation consists of two studies which can help researchers and designers understand the core issues of family sleep and address...
Show moreSleep is a vital health issue. In families with young children, sleep problems can influence the physical, emotional, and behavioral health of all family members. Previous studies have investigated sleep as an individual activity, rarely considering the interconnected aspects of sleep among family members. To understand the social aspects of family sleep, this dissertation consists of two studies which can help researchers and designers understand the core issues of family sleep and address them through the design of sleep-support technology. In the first study, I identified sleep as a complex experience entangled with the social dynamics between family members. For example, children's sleep means time not just for children to rest, but for a parent to have self-care. The results suggested how the boundaries that define sleep in terms of time (at night), space (in bedrooms), and unit of analysis (individual-focused) limit designers' opportunities to tackle the deeper sleep issues of families. I also suggest "division of labor" as an important but rarely discussed design concept to enhance family sleep, and as a promising design theme for home technologies that address issues emerging from social dynamics between household members. In the second study, by incorporating the identified themes from the first stage, I designed and tested two types of family-based sleep management prototypes. These prototypes redistributed the sleep-relevant tasks among family members and provided them with chances to reflect on the difficulties and values involved in the tasks. Through the in-the-wild study deploying two design prototypes in home settings, this study empirically revealed the importance of considering social dynamics as a design factor for family sleep management technologies. Implications of future design are discussed.
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Title: A design of a revetment wall for erosion control on Red Cedar river
Creator: Holgate, Joseph
Date: 1948
Collection: Electronic Theses & Dissertations

Title: On the evolution of mutation bias in digital organisms
Creator: Rupp, Matthew
Date: 2011
Collection: Electronic Theses & Dissertations
Description: Mutation is one of the primary drivers of genetic change. In this work I study mutation biases, which are sets of different genetic-state inflow probabilities. Mutation biases have the potential to change the composition of genomes over time, leading to divergent short- and long-term evolutionary outcomes. I use digital organisms, self-replicating computer programs, to explore whether or not mutation biases are capable of altering the long-term adaptive behavior of populations; whether...
Show moreMutation is one of the primary drivers of genetic change. In this work I study mutation biases, which are sets of different genetic-state inflow probabilities. Mutation biases have the potential to change the composition of genomes over time, leading to divergent short- and long-term evolutionary outcomes. I use digital organisms, self-replicating computer programs, to explore whether or not mutation biases are capable of altering the long-term adaptive behavior of populations; whether mutation biases can be competitive traits; and whether mutation biases can evolve. I find that mutation biases can alter the long-term adaptive behavior of mutation bias-obligate populations in terms of both mean fitness and complex trait evolution. I also find that mutation biases can compete against one another under a variety of conditions, meaning mutation bias can selectable over relatively-short periods of time. The competitive success of a mutation bias does not always depend upon the presence of beneficial mutations, implicating an increase in the probability of neutral mutations as a sufficient mechanism for bias selection. Finally, I demonstrate that by giving organisms a mutable mutation bias allele, populations preferentially evolve to possess specific biases over others. Overall, this work shows that mutation bias can act as a selectable trait, influencing the evolution of populations with regard to both their internal-genetic and external environments.
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Title: Advances in oscillometric blood pressure measurement
Creator: Chandrasekhar, Anand
Date: 2019
Collection: Electronic Theses & Dissertations
Description: High blood pressure (BP) is a major cardiovascular risk factor that is treatable, yet hypertensionawareness and control rates are low. Ubiquitous BP monitoring technology could improve hypertensionmanagement, but existing devices require an inflatable cuff and are not compatible withsuch anytime, anywhere measurement of BP. Oscillometry is the blood pressure (BP) measurementprinciple of most automatic cuff devices. We extended the oscillometric principle, which is usedby most automatic cuff...
Show moreHigh blood pressure (BP) is a major cardiovascular risk factor that is treatable, yet hypertensionawareness and control rates are low. Ubiquitous BP monitoring technology could improve hypertensionmanagement, but existing devices require an inflatable cuff and are not compatible withsuch anytime, anywhere measurement of BP. Oscillometry is the blood pressure (BP) measurementprinciple of most automatic cuff devices. We extended the oscillometric principle, which is usedby most automatic cuff devices, to develop a couple of instruments to measure cuff-less BP usinga smartphone-based device and standalone iPhone application. As the user presses her/his fingeragainst the smartphone, the external pressure of the underlying artery is steadily increased while thephone measures the applied pressure and resulting variable amplitude blood volume oscillations.A smartphone application provides visual feedback to guide the amount of pressure applied overtime via the finger pressing and computes systolic and diastolic BP from the measurements.We prospectively tested the smartphone-based device for real-time BP monitoring in humansubjects to evaluate usability (n = 30) and accuracy against a standard automatic cuff-based device(n = 32). We likewise tested a finger cuff device, which uses the volume-clamp method of BPdetection. About 90% of the users learned the finger actuation required by the smartphone-baseddevice after one or two practice trials. The device yielded bias and precision errors of 3.3 and 8.8mmHg for systolic BP and [Special character(s) omitted]5:6 and 7:7 mmHg for diastolic BP over a 40 to 50 mmHg range of BP.These errors were comparable to the finger cuff device. Cuff-less and calibration-free monitoringof systolic and diastolic BP may be feasible via a smartphone. In addition, we tested the iPhoneapplication. The application yielded bias and precision errors of -4.0 and 11.4 mmHg for systolicBP and -9.4 and 9.7 mmHg for diastolic BP (n = 18). These errors were near the finger cuff deviceerrors. This proof-of-concept study surprisingly indicates that cuff-less and calibration-free BPmonitoring may be feasible with many existing and forthcoming smartphones.These devices use empirical algorithms, already descried in the literature, to estimate bloodpressure. Hence, the next objective was to establish formulas to explain three popular empiricalalgorithms- the maximum amplitude, derivative, and fixed ratio algorithms. A mathematicalmodel of the oscillogram was developed and analyzed to derive parametric formulas for explainingeach algorithm. Exemplary parameter values were obtained by fitting the model to measuredoscillograms. The model and formulas were validated by showing that their predictions correspondto measurements. The formula for the maximum amplitude algorithm indicates that it yields aweighted average of systolic and diastolic BP (0.45 and 0.55 weighting) instead of commonlyassumed mean BP. The formulas for the derivative algorithm indicate that it can accurately estimatesystolic and diastolic BP (<1.5 mmHg error), if oscillogram measurement noise can be obviated.The formulas for the fixed ratio algorithm indicate that it can yield inaccurate BP estimates, becausethe ratios change substantially (over a 0.5-0.6 range) with arterial compliance and pulse pressureand error in the assumed ratio translates to BP error via large amplification (>40). The establishedformulas allow for easy and complete interpretation of perhaps the three most popular oscillometricBP estimation algorithms in the literature while providing new insights. The model and formulasmay also be of some value towards improving the accuracy of automatic cuff BP measurementdevices.
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Title: Toward a sustainable online Q&A community via design decisions based on individuals' expertise : evidence from simulations
Creator: Liang, Yuyang
Date: 2020
Collection: Electronic Theses & Dissertations
Description: Online Q&A communities have become an important channel for internet users to seek information and share knowledge. Existing research extensively focuses on the individual components of Q&A communities, such as content quality and user characteristics, but fails to provide a comprehensive understanding of the communities as complex social systems, whose behavior depends on the interactions of a large number of social agents. In this dissertation, I integrated the key components in online Q&A...
Show moreOnline Q&A communities have become an important channel for internet users to seek information and share knowledge. Existing research extensively focuses on the individual components of Q&A communities, such as content quality and user characteristics, but fails to provide a comprehensive understanding of the communities as complex social systems, whose behavior depends on the interactions of a large number of social agents. In this dissertation, I integrated the key components in online Q&A communities via agent-based modeling to provide a systematic examination of Q&A communities and help inform better community design to manage users' expertise. I conducted computer simulations and virtual experiments based on existing findings and theories as well as data from a large online Q&A community to understand how two design decisions, including expertise indication and question routing, influence the sustainability of a Q&A community as well as result in possible trade-offs involved in implementing these design decisions. Results indicate that these design decisions are likely to lead to a larger membership size and a higher rate of solved questions. In addition, implementing design decisions will also influence the member structure of a community. Question routing tends to prioritize experts' needs and benefits while expertise indication is more likely to attract beginners. These findings suggest that these design decisions should be leveraged according to the development stage a community is in. This research also demonstrates the value of agent-based modeling in terms of generating insights for Q&A community design by showing the underlying structural outcomes of the design decisions.
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Title: Targeting metabolic vulnerabilities in breast cancer subtypes
Creator: Ogrodzinski, Martin Peter
Date: 2020
Collection: Electronic Theses & Dissertations
Description: Breast cancer is a highly prevalent and deadly disease. Globally, it is the most diagnosed cancer in women and is responsible for the most cancer-related deaths among women. Breast cancer is also a remarkably heterogeneous disease, with clear variability in clinical parameters including histological presentation, receptor status, and gene expression patterns that differ between patients. A significant amount of effort has been spent characterizing breast cancer into subtypes, with the main...
Show moreBreast cancer is a highly prevalent and deadly disease. Globally, it is the most diagnosed cancer in women and is responsible for the most cancer-related deaths among women. Breast cancer is also a remarkably heterogeneous disease, with clear variability in clinical parameters including histological presentation, receptor status, and gene expression patterns that differ between patients. A significant amount of effort has been spent characterizing breast cancer into subtypes, with the main goal of improving patient outcomes by: 1) designing targeted therapies, and 2) improving our ability to determine patient prognosis. While scientists have made significant strides in meeting these goals, we still lack targeted therapies for some subtypes of breast cancer, and current therapies often fail to provide a lasting cure. Thus, additional research is needed to improve patient care. One promising area in breast cancer research is cancer metabolism. Using metabolism as a therapeutic target is rapidly gaining traction, as it is now widely appreciated that cancer cells exhibit significant differences in metabolism compared to normal cells. The primary goal of this dissertation is to study the metabolism of distinct subtypes of breast cancer and identify metabolic vulnerabilities that can be used to effectively treat each subtype.This thesis will begin with a review of current classification strategies for breast cancer subtypes and knowledge regarding subtype-specific metabolism. It will also consider modern techniques for targeting breast cancer metabolism for therapeutic benefit. Breast cancer heterogeneity and metabolism are investigated using cell lines and tumors derived from the MMTV-Myc mouse model, which mimics the complexity observed in human disease. Cell lines derived from two histologically defined subtypes, epithelial-mesenchymal transition (EMT) and papillary, are used to establish clear metabolic profiles for each subtype. Metabolic vulnerabilities are identified in glutathione biosynthesis and the tricarboxylic acid cycle in the EMT subtype and nucleotide biosynthesis is determined to be a metabolic weakness in the papillary subtype. It is further shown that pharmacologically targeting each of these metabolic pathways has the greatest effect on reducing proliferation when used against the vulnerable subtype. These in vitro findings are then expanded upon by integrating genomic and metabolomic data acquired from in vivo tumors. In vivo experiments reveal that the EMT and papillary tumors prefer parallel pathways to generate nucleotides, with the EMT subtype preferring to salvage nucleotides while the papillary subtype prefers to produce nucleotides de novo. CRISPR/Cas9 gene editing is used to functionally characterize the metabolic effects of targeting nucleotide salvage and de novo biosynthesis in the EMT and papillary subtypes, and determine that targeting the preferred pathway of each subtype is most effective at slowing tumor growth.Overall, this work demonstrates the power of using metabolism as a therapeutic target of breast cancer, and further shows that metabolic vulnerabilities specific to individual subtypes can be used effectively to guide personalized medicine.
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Title: Efficient and secure system design in wireless communications
Creator: Song, Tianlong
Date: 2016
Collection: Electronic Theses & Dissertations
Description: Efficient and secure information transmission lies in the core part of wireless system design and networking. Comparing with its wired counterpart, in wireless communications, the total available spectrum has to be shared by different services. Moreover, wireless transmission is more vulnerable to unauthorized detection, eavesdropping and hostile jamming due to the lack of a protective physical boundary.Today, the two most representative highly efficient communication systems are CDMA (used...
Show moreEfficient and secure information transmission lies in the core part of wireless system design and networking. Comparing with its wired counterpart, in wireless communications, the total available spectrum has to be shared by different services. Moreover, wireless transmission is more vulnerable to unauthorized detection, eavesdropping and hostile jamming due to the lack of a protective physical boundary.Today, the two most representative highly efficient communication systems are CDMA (used in 3G) and OFDM (used in 4G), and OFDM is regarded as the most efficient system. This dissertation will focus on two topics: (1) Explore more spectrally efficient system design based on the 4G OFDM scheme; (2) Investigate robust wireless system design and conduct capacity analysis under different jamming scenarios. The main results are outlined as follows.First, we develop two spectrally efficient OFDM-based multi-carrier transmission schemes: one with message-driven idle subcarriers (MC-MDIS), and the other with message-driven strengthened subcarriers (MC-MDSS). The basic idea in MC-MDIS is to carry part of the information, named carrier bits, through idle subcarrier selection while transmitting the ordinary bits regularly on all the other subcarriers. When the number of subcarriers is much larger than the adopted constellation size, higher spectral and power efficiency can be achieved comparing with OFDM. In MC-MDSS, the idle subcarriers are replaced by strengthened ones, which, unlike idle ones, can carry both carrier bits and ordinary bits. Therefore, MC-MDSS achieves even higher spectral efficiency than MC-MDIS.Second, we consider jamming-resistant OFDM system design under full-band disguised jamming, where the jamming symbols are taken from the same constellation as the information symbols over each subcarrier. It is shown that due to the symmetricity between the authorized signal and jamming, the BER of the traditional OFDM system is lower bounded by a modulation specific constant. We develop an optimal precoding scheme, which minimizes the BER of OFDM systems under full-band disguised jamming. It is shown that the most efficient way to combat full-band disguised jamming is to concentrate the total available power and distribute it uniformly over a particular number of subcarriers instead of the entire spectrum. The precoding scheme is further randomized to reinforce the system jamming resistance.Third, we consider jamming mitigation for CDMA systems under disguised jamming, where the jammer generates a fake signal using the same spreading code, constellation and pulse shaping filter as that of the authorized signal. Again, due to the symmetricity between the authorized signal and jamming, the receiver cannot really distinguish the authorized signal from jamming, leading to complete communication failure. In this research, instead of using conventional scrambling codes, we apply advanced encryption standard (AES) to generate the security-enhanced scrambling codes. Theoretical analysis shows that: the capacity of conventional CDMA systems without secure scrambling under disguised jamming is actually zero, while the capacity can be significantly increased by secure scrambling.Finally, we consider a game between a power-limited authorized user and a power-limited jammer, who operate independently over the same spectrum consisting of multiple bands. The strategic decision-making is modeled as a two-party zero-sum game, where the payoff function is the capacity that can be achieved by the authorized user in presence of the jammer. We first investigate the game under AWGN channels. It is found that: either for the authorized user to maximize its capacity, or for the jammer to minimize the capacity of the authorized user, the best strategy is to distribute the power uniformly over all the available spectrum. Then, we consider fading channels. We characterize the dynamic relationship between the optimal signal power allocation and the optimal jamming power allocation, and propose an efficient two-step water pouring algorithm to calculate them.
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Title: Design and simulation of a microwave powered microplasma system for local area materials processing
Creator: Narendra, Jeffri Julliarsa
Date: 2010
Collection: Electronic Theses & Dissertations
Description: A microwave powered microplasma source is developed and tested for materials processing on spatially localized areas. A small diameter stream of plasma (less than 2 mm in diameter) is created by focusing microwave energy inside a discharge tube. The discharge then flows out the end of the tube onto the surface being processed delivering ions and reactive radicals. The diameter of the plasma stream from the tube to the material being processed can be controlled by an aperture mounted at the...
Show moreA microwave powered microplasma source is developed and tested for materials processing on spatially localized areas. A small diameter stream of plasma (less than 2 mm in diameter) is created by focusing microwave energy inside a discharge tube. The discharge then flows out the end of the tube onto the surface being processed delivering ions and reactive radicals. The diameter of the plasma stream from the tube to the material being processed can be controlled by an aperture mounted at the end of the tube. The spot size of the localized plasma stream ranges from 2 mm down to 10's micrometers depending on the aperture size. The discharge is created by using 2.45 GHz microwave energy that is coupled into the discharge using a small foreshortened cylindrical cavity that has a hollow inner conductor and a small capacitive gap at the end of the cavity. A processing gas mixture is fed through a 2 mm inner diameter quartz tube which is located inside the hollow inner conductor of the cavity. This tube is exposed to a high electric field at the small gap end of the cavity thus generating a surface wave plasma. The length of the surface wave discharge in the tube can be extended by increasing the microwave power to the discharge so that the plasma reaches the aperture. The operating pressures range from 0.5 Torr to 100 Torr and the microwave power utilized ranges from a few Watts to 10's Watts. Several properties of the discharge including plasma power density, electron density and electron temperature are measured. The power densities of argon and Ar/O₂ plasma discharges vary from 10's to over 450 W/cm3. The plasma density and electron temperature of argon discharges are measured using a double Langmuir probe placed in the materials processing area. The plasma densities are in the range of 1011 - 1013 cm-3.Computational modeling of the plasma discharge and the microwave excitation of the discharge is performed using a finite element analysis. The goal of the modeling study is to complement and understand the design, development and operation of the microwave powered microplasmas. A self-consistent model of the foreshortened cylindrical cavity and plasma discharge is presented with results compared to experimental measurements. The microplasma system is incorporated into a micromanufacturing system that integrates the plasma source with an atomic force microscope for surface measurements and nanomanipulation of the surface. Selected applications of the micromachining system demonstrated include using the microplasma as a spatially localized etcher, free radical source, and ultraviolet light source. Silicon and ultrananocrystalline (UNCD) diamond etching is performed using Ar/SF₆ and Ar/O₂ discharges, respectively, with etching rates of 0.2 - 2 μm/min and 0.6 - 2 μm/hr. Localized removal of photoresist is done by using the microplasma as a free radical source and photoresist is exposed to ultraviolet light from the microplasma source to create spatially localized patterns.
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Title: Environments Effect on Mood : A Comparative Analysis of Environments on Mood Enhancement
Creator: Hayes, Jonah
Date: 2021
Collection: Electronic Theses & Dissertations
Description: Mental health is an issue that millions of people are suffering and struggling with, reconnecting with natural environments could be part of the solution to this problem. Although research demonstrated the significance of the healing properties of natural environments, little research compared natural environments to each other. This research explores which aspects of different natural environments have a positive impact on mood. Using survey questionnaires, two environments were tested. The...
Show moreMental health is an issue that millions of people are suffering and struggling with, reconnecting with natural environments could be part of the solution to this problem. Although research demonstrated the significance of the healing properties of natural environments, little research compared natural environments to each other. This research explores which aspects of different natural environments have a positive impact on mood. Using survey questionnaires, two environments were tested. The first being natural environments, where participant exposure to man-made or urban elements is limited and they are surrounded by natural elements. The second environment, urban environments, are spaces such as parks that are not separated from the urban environment. While in the urban environments’ participants were still able to perceive the urban elements that surrounds the space, such as cars, buildings, and roads. Participants were surveyed before and after using the spaces to allow the measuring and analysis of the change the participants experienced. Both the change in mental restoration, but also of the perceived variables of the space. Statistical analysis of the survey responses showed that a greater amount of change to the perceived variables, and mental restoration happened in natural environments, but both environments were restorative. This supports the idea that accessibility to a diverse set of environments and recreational elements will increase mental restoration. Therefore, policy practitioners, and designers should work to increase park space accessibility to a diverse set of environments and recreation amenities.
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Title: Investigation of planar terahertz passive devices and coupling methods for on-wafer applications
Creator: Myers, Joshua Carl
Date: 2015
Collection: Electronic Theses & Dissertations
Description: In recent years, developments have pushed the cut-off frequencies of transistors near 1 THz, enabling for the first time the design of large bandwidth transmit/receive modules. While there has been a significant interest in the research community to implement these devices, many challenges have slowed such progress. Primarily, these challenges stem from the high dielectric and metal losses many materials display in the THz spectrum. However, to implement wafer-level integrated circuits in the...
Show moreIn recent years, developments have pushed the cut-off frequencies of transistors near 1 THz, enabling for the first time the design of large bandwidth transmit/receive modules. While there has been a significant interest in the research community to implement these devices, many challenges have slowed such progress. Primarily, these challenges stem from the high dielectric and metal losses many materials display in the THz spectrum. However, to implement wafer-level integrated circuits in the THz spectrum, efficient passive devices that are integration compatible must be developed. For any integrated system, many of the most important passive building blocks of the system are reduced to efficient waveguiding, filtering, and coupling between any active components, necessary measurement systems, and input sources. In this dissertation, efficient passive terahertz components, including waveguides, filters, and input couplers, are developed. First, a method of efficiently coupling THz radiation between commercial quasi-optical THz systems and integration compatible THz components is introduced. The primary method developed is the use of high-density polyethylene focusing probes which can be easily fabricated so that they are compatible with commercial THz systems. The efficiency of the probes are then investigated when used with a simple silicon-based dielectric waveguide. Next, dielectric ridge waveguides made of silicon are investigated for low loss THz wave propagation. A theoretical effective index method is applied to determine the modal propagation properties of the waveguides as well as the attenuation of the structures. FEM simulation is also carried out to verify these results. Various ridge waveguides made on silicon wafers are investigated through measurement and determined to provide low-loss waveguiding properties in the THz spectrum. The focus is then shifted to the design of thin-film integration compatible THz filters. These filters are designed with multi-objective evolutionary algorithms coupled with FEM modeling. Bandwidth, stopband characteristics, multi-resonance, and other properties of the filters are developed and improved through optimization. The filters are measured using a commercial THz system, and shown to match well with the optimized expectations.Finally, another waveguiding structure is introduced which is built with thin-metal periodic structures on thin-film substrates. These structures efficiently guide THz waves along the surface of the textured metal structures. With these structures, other passive THz circuits, such as power splitters and sensors, are also developed. The waveguiding structures, as well as power splitter, are measured in conjunction with the dielectric focusing probes developed previously, and show to provide high transmission properties at specific design frequencies. Throughout this dissertation efficient waveguides, filters, and coupling methods are introduced. These methods are compatible with current semiconductor fabrication techniques, enabling device realization directly on-wafer. In addition, all of the passive devices that are developed are simple to fabricate, as well as low-cost. Through the work presented in this dissertation, the realization of passive building blocks for on-wafer active THz circuits are developed, which in turn provides the possible realization of active on-wafer THz circuits.
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Title: A unique approach to frequency-modulated continuous-wave radar design
Creator: Charvat, Gregory Louis
Date: 2003
Collection: Electronic Theses & Dissertations

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