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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: 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: 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: 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

Title: Framework for incorporating rutting prediction model in the reliability-based design of flexible pavements
Creator: Kim, Hyung Bae
Date: 1999
Collection: Electronic Theses & Dissertations

Title: A method for employing qualitative data in the development of spatial agent-based models
Creator: Molen, Nicholas
Date: 2016
Collection: Electronic Theses & Dissertations
Description: Developers of agent-based models of socioecological systems are in a power-laden relationship with those they presume to model. It has often been the case that these developers do not inform their model with any sort of rich cultural data, and instead rely upon established methods from areas such as economics, laboratory psychology, and machine learning. While these methods can be effective, ignoring the perspective of the humans being represented in an ABM risks validation of that model for...
Show moreDevelopers of agent-based models of socioecological systems are in a power-laden relationship with those they presume to model. It has often been the case that these developers do not inform their model with any sort of rich cultural data, and instead rely upon established methods from areas such as economics, laboratory psychology, and machine learning. While these methods can be effective, ignoring the perspective of the humans being represented in an ABM risks validation of that model for the wrong reasons and a marginalization of the humans represented in the model. Qualitative data collection methods, such as the collection of narratives, can aid not only in the elucidation of cultural ecological complexity, but also in the anchoring of an ABM to the political and ecological perspectives presented. While qualitative methods might lead to ABMs with higher fidelity to their real-world counterparts without as many power issues, making use of qualitative data during model development can be quite challenging, and no clear general methods exist. This thesis proposes a method to utilize long-form key informant narratives in the development of spatial agent-based models by linking the textual analysis of source documents to multiple modeling steps utilizing mental mapping and Object-Process Methodology extended for Multi-Agent-Systems (OPM/MAS). To test this method, narratives from migrants during the American Dust Bowl were analyzed and used to construct grounded models. The resulting model of a migrant agent is simple, easily understood and implemented, and its components can be linked directly to elements in the source narratives.
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Title: Natural landscaping, a comparison of design treatments in a surface mine setting
Creator: Wang, Lishuang
Date: 2013
Collection: Electronic Theses & Dissertations
Description: Planners, designers, scientists, and citizens are interested in rehabilitation, reclamation and protection of the post-mining environment. Consequently, a fair amount of research from scholars is focused on the technical aspects concerning the revegetation of the landscape and the science of reclamation; while only a small portion of the literature concerns planning and design. In this thesis, a case study in the Upper Peninsula of Michigan is used to explore post-ming treatments: abandoned...
Show morePlanners, designers, scientists, and citizens are interested in rehabilitation, reclamation and protection of the post-mining environment. Consequently, a fair amount of research from scholars is focused on the technical aspects concerning the revegetation of the landscape and the science of reclamation; while only a small portion of the literature concerns planning and design. In this thesis, a case study in the Upper Peninsula of Michigan is used to explore post-ming treatments: abandoned mine, resort development. a super hotel resot, and natural vegetation communities. The treatments (k=4) were evaluated with an environmental quality measure upon 10 images from each treatment (b=10). The results indicated that the resort and the natural community were best treatments, significantly better than the abandoned mine treatment (p<0.05). The super hotel was ranked as the third, which is less preferred than the two best treatments, but much better than the abandoned mine treatment (p<0.05). By identifying difference between each treatment, the results shows people have preference for natural environment and natural landscape is beautiful in their views.
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Title: Impact of color on children's play behaviors
Creator: Safferman, Bridget Nicole
Date: 2015
Collection: Electronic Theses & Dissertations
Description: IMPACT OF COLOR ON CHILDREN’S PLAY BEHVIORSByBridget Nicole SaffermanThis research examines the effects of differently colored playground balls on the play behaviors of children between the ages of three and four. Color vision in human beings triggers certain physical and psychological responses that can influence behavioral changes; the goal of this observational study is to determine if these responses are strong enough to influence the type and durations of children’s play. This...
Show moreIMPACT OF COLOR ON CHILDREN’S PLAY BEHVIORSByBridget Nicole SaffermanThis research examines the effects of differently colored playground balls on the play behaviors of children between the ages of three and four. Color vision in human beings triggers certain physical and psychological responses that can influence behavioral changes; the goal of this observational study is to determine if these responses are strong enough to influence the type and durations of children’s play. This observational study was conducted on children between the ages of 36 and 60 months old who were enrolled in a children’s daycare and child development research facility. Results of this study produced trends that indicate that certain colors do have an impact on the level of activity in which children play, namely, that children exhibit a greater number of play behaviors on traditional playgrounds, but play longer on nature playgrounds. Additionally, trends suggested that red and yellow, warm colors, increase the number of active and low active play behaviors observed and blue, a cool color, increases the durations of play behaviors. This knowledge suggest that color could be a viable tool in designing play spaces to meet specific needs and promoting different play behaviors in childrenKeywords: Color, Children’s Play Behaviors, Children’s Play Durations, Level of Activity
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Title: Wide-band antenna design for use in minimal-scan, microwave tomographic imaging
Creator: Klaser, Jacob
Date: 2013
Collection: Electronic Theses & Dissertations
Description: Microwave tomography is widely used in biomedical imaging and nondestructive evaluation of dielectric materials. A novel microwave tomography system that uses an electrically-conformable mirror to steer the incident energy for producing multi-view projection data is being developed in the Non-Destructive Evaluation Laboratory (NDEL). Such a system will have a significant advantage over existing tomography systems in terms of simplicity of design and operation, particularly when there is...
Show moreMicrowave tomography is widely used in biomedical imaging and nondestructive evaluation of dielectric materials. A novel microwave tomography system that uses an electrically-conformable mirror to steer the incident energy for producing multi-view projection data is being developed in the Non-Destructive Evaluation Laboratory (NDEL). Such a system will have a significant advantage over existing tomography systems in terms of simplicity of design and operation, particularly when there is limited-access of the structure that is being imaged. The major components of a mirror-based tomography system are the source mirror assembly, and a receiver array for capturing the multi-view projection data. This thesis addresses the design and development of the receiver array. This imaging array features balanced, anti-podal Vivaldi antennas, which offer large bandwidth, high gain and a compact size. From the simulations, as well as the experimental results for the antenna, the return loss (S11) is below -10dB for the range from 2.2GHz to 8.2GHz, and the gain is measured to be near 6dB. The data gathered from the receiver array is then run through MATLAB code for tomographic reconstruction using the Filtered Back-Propagation algorithm from limited-view projections. Initial results of reconstruction from the measured data shows the feasibility of the approach, but a significant challenge remains in interpolating the data for a limited number of receiving antenna elements and removing noise from the reconstructed image.
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Title: A methodology for material design applied to porous media with flow
Creator: Bandyopadhyay, Deep
Date: 2008
Collection: Electronic Theses & Dissertations

Title: The design of a bus terminal for Lansing, Mich
Creator: Edwards, William B.
Date: 1932
Collection: Electronic Theses & Dissertations

Title: Diagnostic tools for improving the amount of adaptation in adaptive tests using overall and conditional indices of adaptation
Creator: Ju, Unhee
Date: 2019
Collection: Electronic Theses & Dissertations
Description: In recent years, computerized adaptive testing (CAT) has been widely used in educational and clinical settings. The basic idea of CAT is relatively straightforward. A computer is used to administer items tailored for individuals to maximize the measurement precision of their proficiency estimates. However, the administration of CAT is not so simple. Those who administer CATs must, while trying to optimize an item selection criterion, consider a variety of practical issues such as test...
Show moreIn recent years, computerized adaptive testing (CAT) has been widely used in educational and clinical settings. The basic idea of CAT is relatively straightforward. A computer is used to administer items tailored for individuals to maximize the measurement precision of their proficiency estimates. However, the administration of CAT is not so simple. Those who administer CATs must, while trying to optimize an item selection criterion, consider a variety of practical issues such as test security, content balancing, the purpose of testing, and other test specifications. Such extraneous factors make it possible that a CAT might have so many constraints that in practice it is barely adaptive at all. This concern is at the forefront of the current study, which poses two key questions: How adaptive is a highly adaptive test really? How can the level of adaptation be improved? This study aims to develop three new statistical indicators to measure the amount of adaptation conditional on the examinees' proficiency levels in CAT. It also aims to evaluate the feasibility and utility of these adaptation measures in helping to diagnose and improve adaptivity that occurs during the CAT administration. Extending work done by Reckase, Ju, and Kim (2018), the proposed measures are based on three components-the differences in the locations between the selected items and the examinee's current proficiency estimates, the variations in the item locations administered to each examinee, and the magnitude of information that the test presents to each examinee. Hence, they can be used to assess adaptivity during the CAT process, as well as to identify differences in the level of adaptation for individuals or subgroups of examinees. To demonstrate the performance of the proposed adaptation indices, this study conducted analyses of real operational testing data from a healthcare licensure examination, as well as comprehensive simulation studies under various conditions that affect adaptivity in a CAT. The key findings of the study suggest that the proposed adaptation indices are likely to function as intended to sensitively detect the magnitude of adaptivity for a CAT over the proficiency continuum. These new measures shed light on how much adaptation of a given test occurs across individual proficiency levels or subpopulations. With some guidelines for the interpretation of these measures recommended in this study, the adaptation indices can also readily serve as diagnostic tools in practice for helping test practitioners design item pools and adaptive tests that support high adaptivity.
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Title: Extended operational range of a feedback-controlled optical microphone for aeroacoustics research
Creator: Feeney, Sara
Date: 2012
Collection: Electronic Theses & Dissertations
Description: This study is an extension of a previous study conducted at MSU on a feedback-controlled optical microphone for potential use in "beam-forming" arrays employing anywhere from thirty to one hundred microphones in aeroacoustics research. The membrane of the microphone is made from PVDF (polyvinylidene-fluoride), a material with piezoelectric properties, giving a means for opposing the sound-produced deflection of the membrane using a feedback loop. The feedback capability of the microphone...
Show moreThis study is an extension of a previous study conducted at MSU on a feedback-controlled optical microphone for potential use in "beam-forming" arrays employing anywhere from thirty to one hundred microphones in aeroacoustics research. The membrane of the microphone is made from PVDF (polyvinylidene-fluoride), a material with piezoelectric properties, giving a means for opposing the sound-produced deflection of the membrane using a feedback loop. The feedback capability of the microphone allows it to self-calibrate and gives it response-matching capabilities in array applications---a unique advantage over current microphone technology, as manual, individual calibration of each microphone in an array can be time-consuming.The present research goal is to extend the operational range of the microphone. Two provisions were proposed to accomplish this goal: the addition of a microphone back-plate with small holes to create a means to damp the membrane motion; also, by employing an optical sensor that measures membrane displacement averaged over an area rather than at a point, as used in the previous study, to attenuate the high-order resonance modes which cause instability in the control. The improved feedback microphone will ultimately enhance the capability of "beam-forming" arrays used for research. The results show that individually, each of the damping and area-averaged sensing was able to improve the operational range of the microphone, and together, they combined for an even greater improvement in stability, leading to tripling of the bandwidth of the baseline open-loop microphone.
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