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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: A cluster analysis comparison of garden activities in classical Chinese gardens and American gardens
Creator: Wang, Xiaoyi (Graduate of Michigan State University)
Date: 2019
Collection: Electronic Theses & Dissertations
Description: Activities that occurred in Chinese classical gardens and American gardens are an important part of their traditional culture. The purpose of this study is to explore the similarities and differences between Chinese classical gardens and American gardens. Six classical Chinese gardens in China and five American gardens in the United States were selected to test. Eighty-five possible activities were selected based on site visits and from historical documents. A method named principal component...
Show moreActivities that occurred in Chinese classical gardens and American gardens are an important part of their traditional culture. The purpose of this study is to explore the similarities and differences between Chinese classical gardens and American gardens. Six classical Chinese gardens in China and five American gardens in the United States were selected to test. Eighty-five possible activities were selected based on site visits and from historical documents. A method named principal component analysis with plots was applied to this research. After applying the variables into the software SAS, a number of eigenvalues were generated, and the first three eigenvalues representing almost 75% of the variance were used for further analysis. The result shows a distinctive difference between Chinese garden and American garden. The first principal component indicates the major element that differ the Chinese garden and American garden, with activities occurred only in Chinese gardens such as literati gathering, writing calligraphy, and examine antiques; and activities occurred only in American gardens such as barbecuing, making bonfires, and playing ball games. The second and third principal components explained the difference between Chinese gardens, which varies primarily because of the garden owner's lifestyle.
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Title: The design and synthesis of novel proteasome inhibitors : studies on the synthesis of nagelamide M and analogs, the synthesis of rapamycin based proteasome inhibitors, and the synthesis of TCH based molecular probes for binding site determination
Creator: Giletto, Matthew Basil
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "The two primary physiologic mechanisms for the recycling of amino acids from no-longer needed or damaged proteins are autophagy and enzymatically via the proteasome. Inhibition of the proteasome has emerged as the preeminent means for treating cancers that constitutively overproduce proteins, particularly multiple myeloma. Two drugs currently available for the treatment of multiple myeloma, BortezomibTM and KyprolisTM, inhibit the proteasome by binding to the catalytically active sites...
Show more"The two primary physiologic mechanisms for the recycling of amino acids from no-longer needed or damaged proteins are autophagy and enzymatically via the proteasome. Inhibition of the proteasome has emerged as the preeminent means for treating cancers that constitutively overproduce proteins, particularly multiple myeloma. Two drugs currently available for the treatment of multiple myeloma, BortezomibTM and KyprolisTM, inhibit the proteasome by binding to the catalytically active sites through a competitive mechanism. While initially effective, over time the resistance that is typical of competitive binders emerges, and relapse rates are currently measured at 97 %, with the average survival time after being one year. Additionally the most common side effect is neuropathy, which typically does not abate after discontinuation of chemotherapy. The current state of the art demonstrates the need not only for new proteasome inhibitors, but inhibitors that act through a different mechanism. The Tepe group was the first to develop such a molecule, imidazolines of the TCH-series, which bind to the proteasome via a noncompetitive mechanism. The details of the interaction of these molecules with the proteasome have been extensively studied, but the location of the binding site remains elusive. In this work, several molecular probes were designed and synthesized (two diazirine photoaffinity-TCH hybrids and a biotin-TCH hybrid) to elucidate the location of the binding site. Currently biological testing is underway. Additionally, a library of analogs based on the natural product rapamycin were designed and synthesized. An analog was discovered that was equipotent to the natural product itself, which could be synthesized on a gram scale in three steps from commercially available materials. To discover the binding site of these molecules, a diazirine photoaffinity probe was designed and synthesized. Enough biological data was generated to refine the library and design and synthesize a second generation of the analogs; currently biological testing of these analogs is underway. Lastly, extensive studies on the total synthesis of the pyrrole-imidazole natural product nagelamide M were designed and performed. These studies relied mainly on the use of C-H activation to functionalize a methylene C-H bond adjacent to a heteroatom. None of the key reactions were successful, and the synthesis stalled at an early stage. Overall this thesis describes several advances in the areas of drug discovery and proteasome inhibition, and perhaps most excitingly access to molecules that could elucidate the binding site of the TCH molecules."--Pages ii-iii.
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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: 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: Design of a coal storage plant, M.A.C. power plant
Creator: Russell, R. S.
Date: 1911
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: 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: 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: 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: A methodology for material design applied to porous media with flow
Creator: Bandyopadhyay, Deep
Date: 2008
Collection: Electronic Theses & Dissertations

Title: Object location and shape estimation using a MIMO FMCW millimeter wave sensor
Creator: Lou, Yun
Date: 2018
Collection: Electronic Theses & Dissertations
Description: Autonomous systems such as self-driving cars and drones are going to transform our lives in many ways. One fundamental element of these systems is the accurate and robust sensing of the surrounding environments. Current solutions involve a multi-modal approach where varieties of sensors are utilized to achieve the best performance. Among all the sensing modalities, millimeter wave radar is playing a critical role due to its high resolution and the capability of sensing in the dark environment...
Show moreAutonomous systems such as self-driving cars and drones are going to transform our lives in many ways. One fundamental element of these systems is the accurate and robust sensing of the surrounding environments. Current solutions involve a multi-modal approach where varieties of sensors are utilized to achieve the best performance. Among all the sensing modalities, millimeter wave radar is playing a critical role due to its high resolution and the capability of sensing in the dark environment. As the cost, size and weight of millimeter wave radars decrease prominently in recent years, there is a significant opportunity to widely adopt it for a variety of sensing tasks.This thesis presents a MIMO FMCW millimeter wave radar system at 77-81 GHz band. It is a small-size and high-accuracy solution for sensing objects in the environment. Our system is designed to estimate the object's surface shape, orientation, curvature, boundaries, and 2D location by detecting the object's surface at multiple positions on a planned trajectory. We evaluated our system on a metal rectangular box and a metal cylinder. The experiment results show that our system is able to determine the surface type (planar or curved) correctly and achieve cm-level accuracy on the boundaries and location estimation. The orientation error is bounded to 2.14 degrees. The curvature estimation is highly accurate for the middle part of the curved surface.
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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: Assessing bikeway design alternatives : DALMAC route centeral Michigan case study
Creator: Li, Yinliang
Date: 2018
Collection: Electronic Theses & Dissertations
Description: The objective of this thesis is to explore the differences and possibilities of bikeway design implemented with different treatments by examining the DALMAC bicycle camping tour. In the following steps, the thesis conducted series of analysis to select the final route by assessing three segments (Site A, Site B, and Site C) as study sites from DALMAC (b = 3). The investigation studied treatment including: 1) Existing Treatment, 2) Balance Treatment, 3) Extremely Safe Treatment, 4) Extremely...
Show moreThe objective of this thesis is to explore the differences and possibilities of bikeway design implemented with different treatments by examining the DALMAC bicycle camping tour. In the following steps, the thesis conducted series of analysis to select the final route by assessing three segments (Site A, Site B, and Site C) as study sites from DALMAC (b = 3). The investigation studied treatment including: 1) Existing Treatment, 2) Balance Treatment, 3) Extremely Safe Treatment, 4) Extremely Enjoyable Treatment, and 5) Extremely Environmental Treatment (k = 5). In order to test the differences among treatments statistically through Freidman Test of variances, there is a scoring criteria consisting of 30 questions. As a result, this data indicated that at least one treatment yield different values among all treatments (p ≤ 0.005 or p ≤ 0.001). Furthermore, among all treatments across 3 sites, the Extremely Enjoyable Treatment statistically performed best (p ≤ 0.05). In conclusion, this thesis investigated the potential values of bicycle enjoyment for a specific segment of DALMAC route.
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Title: Virtual officing trends in the practice of landscape architecture
Creator: Boyer, Douglas E.
Date: 2013
Collection: Electronic Theses & Dissertations
Description: This research examines trends in virtual officing in project-based organizations such as landscape architecture firms. Virtual officing is the process of employees conducting business full-time in designated places other than a central office. Of particular interest is the development of communications technology to allow these new business models to grow and prosper. A survey was distributed by the American Society of Landscape Architects to landscape architecture member firms, with...
Show moreThis research examines trends in virtual officing in project-based organizations such as landscape architecture firms. Virtual officing is the process of employees conducting business full-time in designated places other than a central office. Of particular interest is the development of communications technology to allow these new business models to grow and prosper. A survey was distributed by the American Society of Landscape Architects to landscape architecture member firms, with questions focusing on their business practices and virtual officing trends. It was found that virtual officing usage is on the rise in landscape architecture firms. Trends in hiring also were positively affected by the presence of virtual officing, showing a correlation between this new business model and the overall strength of a firm. -- Abstract.
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Title: Context sensitive design : a non-transportation example in Michigan
Creator: Wang, Yun
Date: 2012
Collection: Electronic Theses & Dissertations
Description: In recent decades, the conflict between environmental degradation and development of human society is has been exacerbated. This situation engages planners and designers to minimize the negative human impact, protect and create a healthy ecosystem, reclaim degraded environments while also encouraging a healthy business and cultural climate. Context sensitive design is a philosophy which can help foster such an approach accommodating environmental issues and striking a balance between...
Show moreIn recent decades, the conflict between environmental degradation and development of human society is has been exacerbated. This situation engages planners and designers to minimize the negative human impact, protect and create a healthy ecosystem, reclaim degraded environments while also encouraging a healthy business and cultural climate. Context sensitive design is a philosophy which can help foster such an approach accommodating environmental issues and striking a balance between stakeholders to create an environmental friendly project. In this study, I applied a Context Sensitive Design philosophy for a Ski Resort project in Michigan. I evaluated and compare the Context Sensitive Design project outcomes with three other design solutions/treatments: a Housing Unit design using Le Corbusier's theory for structures, a Forested Woodland Community and an Abandoned Surface Mine condition. To compare the project treatments, I employed a visual quality equation, two habitat models, surface water runoff, and a vegetation diversity index. The statistical results indicated that the Forested Woodland Community was significantly better than the Abandoned Surface Mine condition, but the other treatments were not significantly different from each other.
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Title: Theoretical and numerical study of swirling flow separation devices for oil-water mixtures
Creator: Motin, Abdul
Date: 2015
Collection: Electronic Theses & Dissertations
Description: Oil-water separation is a critical aspect of produced water treatment, oil spill cleanup, and refining of petroleum products. Hydrocyclones are commonly used in these operations. A hydrocyclone is a device that separates two phases based on centrifugal forces acting on the two phases. Conventional hydrocyclones possess a finite turndown ratio and are effective for removing droplets greater than approximately ten microns. The understanding of hydrodynamic phenomena that limit the turndown...
Show moreOil-water separation is a critical aspect of produced water treatment, oil spill cleanup, and refining of petroleum products. Hydrocyclones are commonly used in these operations. A hydrocyclone is a device that separates two phases based on centrifugal forces acting on the two phases. Conventional hydrocyclones possess a finite turndown ratio and are effective for removing droplets greater than approximately ten microns. The understanding of hydrodynamic phenomena that limit the turndown ratio is crucial for improving hydrocyclone performance and finding a device that is reliable, efficient, and that has the potential to decrease the environmental footprint of oil and gas production. In this work, a quantitative understanding of the turndown ratio of an individual class hydrocyclone has been developed. A computational search is applied for redesigning the geometry of different modules of hydrocyclone. In addition, the desirable attributes of a crossflow filter and a vortex separator are combined into one unit to develop a crossflow filtration hydrocyclone (CFFH) for enhancing separation.The hydrodynamic characteristics of single and multiphase flows encountered in hydrocyclones, the trajectories of dispersed droplets, interaction of phases that involve breakup and coalescence of dispersed droplets, and the geometry and operating principles that characterize the performances of a hydrocyclone are investigated based on computational fluid dynamic (CFD) simulations using the Eulerian-Lagrangian, the Eulerian-Eulerian, and a coupled CFD-PBM (Population balance method) approaches. Results show that the finite turndown ratio in conventional hydrocyclones is a hydrodynamic effect that depends on the length of reverse flow core. Tailoring of hydrocyclone geometry with hyperbolic swirl chamber and new underflow outlet geometry significantly increases the separation efficiency and improves the turndown. Based on a parametric study, a novel hydrocyclone design is proposed that is able to achieve desired separation efficiency by a unit operation and possesses a large turndown. CFD studies were also performed on CFFH devices and showed that the swirl can aid in removing droplets from the membrane/filter surface.The novel hydrocyclone identified provides a stable reverse flow core for an increased range of feed Reynolds numbers and yields less energy loss. With increasing the feed Reynolds number, the novel hydrocyclone gradually decreases the cut size (a size of droplet having 50% separation efficiency); this does not appear in a conventional hydrocyclone. For the feed Reynolds number of 60,000, the cut size in the novel hydrocyclone is less than 10 microns whereas the conventional hydrocyclone has a cut size of 65 microns and is ineffective for droplet less than 10 microns.
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Title: A formal approach to providing assurance to dynamically adaptive software
Creator: Zhang, Ji
Date: 2007
Collection: Electronic Theses & Dissertations

Title: Enabling higher energy and power density lithium ion batteries through electrode design and the integration of solid-state electrolytes
Creator: Kim, Yunsung
Date: 2015
Collection: Electronic Theses & Dissertations
Description: At present, Li-ion technology is the leading battery chemistry to enable the large-scale adoption of electric vehicles. However, meeting the demands of hybrid and plug-in hybrid electric vehicles requires higher specific and volumetric energy density, faster charge rates, longer cycle life, and improved safety. A particular focus is on achieving high power density without compromising energy density. This dissertation seeks to determine the phenomena that couple energy and power density and...
Show moreAt present, Li-ion technology is the leading battery chemistry to enable the large-scale adoption of electric vehicles. However, meeting the demands of hybrid and plug-in hybrid electric vehicles requires higher specific and volumetric energy density, faster charge rates, longer cycle life, and improved safety. A particular focus is on achieving high power density without compromising energy density. This dissertation seeks to determine the phenomena that couple energy and power density and to develop solutions to simultaneously increase both. An engineered electrode design is proposed that improves Li-ion transport in thick high energy density electrodes, while suppressing the deleterious formation of Li metal dendrites during charging. Furthermore, a novel hybrid cell design is proposed employing Li7La3Zr2O12 (LLZO) ceramic electrolyte membrane technology, which acts as a physical barrier to prevent Li metal dendrite propagation. The overarching goal of this dissertation is to develop materials and materials processing technology to improve the performance and safety of Li-ion batteries.
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