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- Title
- BUILDING STATE WILDLIFE AGENCY CAPACITY FOR EFFECTIVE PARTNERSHIPS
- Creator
- Cross, Megan M
- Date
- 2022
- Collection
- Electronic Theses & Dissertations
- Description
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State wildlife agencies (SWAs) partner with organizations of various types, on projects of various types, at what is anticipated to be an increasing rate. Inclusion of multiple and diverse stakeholders and partners is postulated to improve effectiveness of wildlife management (Anderson & Loomis, 2007; Jacobson et al., 2010). Through partnerships, actors from private, civil, and public sectors work together to reduce negative impacts from wildlife and improve access to and benefits of wildlife...
Show moreState wildlife agencies (SWAs) partner with organizations of various types, on projects of various types, at what is anticipated to be an increasing rate. Inclusion of multiple and diverse stakeholders and partners is postulated to improve effectiveness of wildlife management (Anderson & Loomis, 2007; Jacobson et al., 2010). Through partnerships, actors from private, civil, and public sectors work together to reduce negative impacts from wildlife and improve access to and benefits of wildlife resources. Although partnerships can improve the ability of SWAs to address these issues, little is known about how the perspectives of internal employees and external partners and stakeholders differ regarding factors affecting perceived success of partnerships in wildlife conservation.This dissertation addresses SWA partnerships through an examination of one prototypical SWA’s partnership arrangements. I propose a typology for categorization of SWA partnerships and apply a theory of collaborative capacity to the assessment of them. I surveyed all employees of the Michigan SWA and asked them to identify the three partners they consider most key to their work and found gaps in the frequencies of partners considered key to the work of SWA employees based on their locations in the defined typology. Additionally, the model of collaborative capacity tested varied in performance when applied to SWA employees and SWA partners. This research has implications for transparency regarding how state power is shared and considers how the disparate prevalence of various partnership arrangements may affect wildlife governance. Furthermore, my research findings may be used to improve SWA partnership arrangements and improve their alignment with governance and management-relate goals, as well as increase awareness of differences in views regarding partnership success as defined by SWA employees and partners.
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- Title
- Life Cycle Monitoring of Reversible Adhesive Bonded Joints using Guided Waves
- Creator
- Palanisamy, Rajendra Prasath
- Date
- 2022
- Collection
- Electronic Theses & Dissertations
- Description
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Recent advancements in automotive, aerospace, civil and wind-energy industries have resulted in an ever-increasing demand for lightweight, cost-effective, rapidly manufactured and recyclable/reusable of structural components. Adopting composite materials is a popular solution to achieve light-weighting, however it requires complex joining methods compared to traditional mechanical fasteners. Electromagnetic targeted heating of nano-Fe3O4 reinforced thermoplastic adhesives (Reversible-Adhesive...
Show moreRecent advancements in automotive, aerospace, civil and wind-energy industries have resulted in an ever-increasing demand for lightweight, cost-effective, rapidly manufactured and recyclable/reusable of structural components. Adopting composite materials is a popular solution to achieve light-weighting, however it requires complex joining methods compared to traditional mechanical fasteners. Electromagnetic targeted heating of nano-Fe3O4 reinforced thermoplastic adhesives (Reversible-Adhesive) is an emerging technique for rapid assembly, dis-assembly, and re-assembly of bonded composite parts. Alternate magnetic field applied to the dispersed ferromagnetic nanoparticles (FMNP) within a thermoplastic adhesive results in these particles acting as nano-heaters and rapidly heating the surrounding material resulting in melting and flow of the adhesive, which upon cooling forms a structural bond. This process can be repeated and hence termed reversible adhesive. Reversible-adhesive bonded composite structures (RBCS) offer a greater advantage over thermosets or mechanical joints such as rapid processing, easy repair, quick disassembly, and possible re-usability of components. However, it is essential to accurately measure the temperature of the adhesive during processing and repair, since overheating may cause chemical degradation and underheating may introduce improper bonds. Adhesively bonded composite structures provide a more uniform stress distribution in the bond-line than riveted joints resulting in higher fatigue life. However, modeling the physics behind crack initiation and propagation inside bonded regions is challenging especially under fatigue loading. As a result, real-time in-service bond monitoring is required to ensure structural safety. In addition to monitoring the damage state, prediction of damage area and remaining useful life of the component is imperative. Thus, this research work focusses on developing a life cycle monitoring solution for RBCS using the guided wave (GW) technique. Ultrasonic guided waves were made to propagate across the bond-line of the joint by exciting and sensing them using miniature piezoelectric wafers. Analysis of dispersion relations and dynamic wave propagation were performed using finite element modeling (FEM). Fundamental longitudinal mode L_0 at 35 kHz was found optimal for bond process monitoring. Mapping between the FE-simulated transmission coefficient of L_0 and actual temperature of the thermoplastic adhesive was established using the DMA test data. Real-time guided wave measurements were used as feedback in the discrete control of the induction heater so as to provide optimal bonding and prevent adhesive degradation. The developed ultrasonic technique was successfully validated by fiber-optic temperature sensing. Results indicate that the bondlines processed with GW control offer better ultimate strength compared to uncontrolled processing.Guided wave modal and frequency sensitivity analysis for fatigue damage was performed. Based on the analysis, symmetric mode at 85 kHz was found optimal for fatigue damage detection. Further, a damage propagation model based on Paris law was developed to estimate remaining useful life in terms of the GW signal features. Finally, the remaining useful life of the lap-joint was predicted and validated experimentally. One of the major advantages of reversible adhesive is its ability to repair/heal the damage. The controlled processing technique developed earlier was used for controlled healing of fatigue damaged joints. Experimental investigation proves the healed-bond line have returned to its original strength. A holistic approach of a complete lifecycle monitoring of bonded joints was aimed at increasing the confidence in the use of bonded joints relative to mechanical fasteners, and can be easily extended to other structural applications.
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- Title
- High-precision and Personalized Wearable Sensing Systems for Healthcare Applications
- Creator
- Tu, Linlin
- Date
- 2022
- Collection
- Electronic Theses & Dissertations
- Description
-
The cyber-physical system (CPS) has been discussed and studied extensively since 2010. It provides various solutions for monitoring the user's physical and psychological health states, enhancing the user's experience, and improving the lifestyle. A variety of mobile internet devices with built-in sensors, such as accelerators, cameras, PPG sensors, pressure sensors, and the microphone, can be leveraged to build mobile cyber-physical applications that collected sensing data from the real world...
Show moreThe cyber-physical system (CPS) has been discussed and studied extensively since 2010. It provides various solutions for monitoring the user's physical and psychological health states, enhancing the user's experience, and improving the lifestyle. A variety of mobile internet devices with built-in sensors, such as accelerators, cameras, PPG sensors, pressure sensors, and the microphone, can be leveraged to build mobile cyber-physical applications that collected sensing data from the real world, had data processed, communicated to the internet services and transformed into behavioral and physiological models. The detected results can be used as feedback to help the user understand his/her behavior, improve the lifestyle, or avoid danger. They can also be delivered to therapists to facilitate their diagnose. Designing CPS for health monitoring is challenging due to multiple factors. First of all, high estimation accuracy is necessary for health monitoring. However, some systems suffer irregular noise. For example, PPG sensors for cardiac health state monitoring are extremely vulnerable to motion noise. Second, to include human in the loop, health monitoring systems are required to be user-friendly. However, some systems involve cumbersome equipment for a long time of data collection, which is not feasible for daily monitoring. Most importantly, large-scale high-level health-related monitoring systems, such as the systems for human activity recognition, require high accuracy and communication efficiency. However, with users' raw data uploading to the server, centralized learning fails to protect users' private information and is communication-inefficient. The research introduced in this dissertation addressed the above three significant challenges in developing health-related monitoring systems. We build a lightweight system for accurate heart rate measurement during exercise, design a smart in-home breathing training system with bio-Feedback via virtual reality (VR) game, and propose federated learning via dynamic layer sharing for human activity recognition.
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