In this thesis, we present theoretical and experimental investigation into the nonlinear statics and dynamics of clamped-clamped in-plane MEMS arches when excited by an electrostatic force. Theoretically, we first solve the equation of motion using a multi- mode Galarkin Reduced Order Model (ROM). We investigate the static response of the arch experimentally where we show several jumps due to the snap-through instability. Experimentally, a case study of in-plane silicon micromachined arch is studied and its mechanical behavior is measured using optical techniques. We develop an algorithm to extract various parameters that are needed to model the arch, such as the induced axial force, the modulus of elasticity, and the initially induced initial rise. After that, we excite the arch by a DC electrostatic force superimposed to an AC harmonic load. A softening spring behavior is observed when the excitation is close to the first resonance frequency due to the quadratic nonlinearity coming from the arch geometry and the electrostatic force. Also, a hardening spring behavior is observed when the excitation is close to the third (second symmetric) resonance frequency due to the cubic nonlinearity coming from mid-plane stretching. Then, we excite the arch by an electric load of two AC frequency components, where we report a combination resonance of the summed type. Agreement is reported among the theoretical and experimental work.

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This dissertation examines the effects of the Supplemental Nutrition Assistance Program or SNAP, formally known as the Food Stamp Program, on adult weight outcomes. The focus of this work is to uncover the causal effects of the program by applying rigorous identification methods as well as techniques that address data limitations. By understanding the true impact of SNAP on adult obesity, policymakers can pursue appropriate reform measures to avoid unintended consequences of the program while promoting healthy weight outcomes for low-income Americans. The first essay expands on previous work examining the effects of SNAP participation on adult obesity. Previous research provides some evidence that SNAP participation may have a small positive effect on weight gain for women and no significant effect on men. However, additional research has found that misreporting of SNAP participation in surveys is prevalent and that analysis of program effects when participation is misclassified (misreported) can produce estimates that are biased and misleading. Until now, nearly all studies examining the effects of SNAP on adult obesity have ignored the issue of respondent misreporting. This chapter uses state-level policy variables regarding SNAP administration to instrument for SNAP participation for NLSY79 respondents. To address respondent misreporting I adopt an approach based on parametric methods for misclassified binary dependent variables that produces consistent estimates when using instrumental variables. This study is the first to document the considerable rates of SNAP participation under-reporting in the NLSY79 dataset. In addition, this study finds that, although SNAP participation increases adult BMI and the likelihood of being obese, without correcting for misreporting bias the estimates are overstated by nearly 100 percent. The second essay uses the same data but applies a different identification strategy to investigate the intensive margin effects of SNAP on adult obesity. To mitigate the severity of endogenous participation and misreporting biases, I employ a strategy that examines only individuals who report participating in SNAP. I utilize a quasi-experimental variation in SNAP amount per adult due to the timing of school eligibility for children. The identification examines the proportion of school-age children in SNAP households who automatically qualify for in-school nutrition assistance programs. A greater proportion of school-age children eligible for free in-school meals proxies for an exogenous increase in the amount of SNAP benefits available per adult. This study finds that increases in SNAP benefits, as proxied by increases in the proportion of school-age children, reduce BMI and the probability of being severely obese for SNAP adults. Taken together, the results of this dissertation present an intriguing depiction of the effects of SNAP on adult obesity that serves to inform both policymakers and future researchers. On the one hand, the findings indicate that participating in SNAP (extensive margin) leads to weight gain and higher rates of obesity. Yet, on the other hand, increases in the amount of benefits for those who report participating in SNAP (intensive margin) actually leads to reductions in weight and the likelihood of being severely obese.

Thesis (M.S.)--University of Michigan, 1964.

Food pantry clients are at an increased risk of poor diet quality which can lead to a variety of chronic diseases. Identifying nutrition interventions that help improve the dietary intake of this vulnerable population is important to help improve health outcomes. Utah’s Supplemental Nutrition Assistance Program-Education (SNAP-Ed), also known as Food $ense, partners with many pantries throughout the state to improve healthy food access. This research was conducted to evaluate the effectiveness of a pantry intervention, Thumbs Up for Healthy Choices, to evaluate its impact on food pantry clients’ selection and use of identified healthy foods. In addition to program evaluation, data identifying interest in programs such as Thumbs Up, as well as common barriers that prevent pantry clients from making healthy choices was also collected and analyzed. This research was funded through a Utah State University (USU) Extension mini-grant for $8,500. The findings will be used to guide future SNAP-Ed initiatives that aim to make the healthy choice the easy choice in food pantries. The results will also be used to build the evidence base for the Thumbs Up for Healthy Choices program, which will allow other SNAP-Ed programs throughout the country to adopt and implement this effective program.

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In the U.S., states vary in the way they link the Supplemental Nutrition Assistance Program (SNAP) and Low-Income Home Energy Assistance Program (LIHEAP). State practices that have come to be known as "Heat and Eat" (HandE) exploit a SNAP energy expense deduction in order to increase SNAP benefits. Sixteen states have used the practice at some point, with the earliest starting in 1995 and latest in 2013. This study uses variation in the timing of adoption of HandE across states to estimate the HandE's effect on SNAP participation. SNAP-LIHEAP participation links are also examined in relation to alternative state policies that bundle application costs. Using SIPP 2008 Panel data, the study employs a household fixed effects model to examine the impact of LIHEAP participation and the three SNAP-LIHEAP bundling policies on SNAP participation propensities. The results indicate that HandE policies cause a small increase in household SNAP participation, which is likely due to the fact that HandE provides additional benefits for SNAP participants. Categorical eligibility that links applications for both programs also generates higher differential probabilities of being on SNAP. These results are consistent with previous findings in the multiple program participation literature. / Master of Science

The Supplemental Nutrition Assistance Program (SNAP) is the largest domestic hunger safety net program in the United States. It has been shown that SNAP increases households' purchasing power. However, only a quarter of Americans follow recommended healthy eating patterns. Hence, there is a question whether the additional income from SNAP transfers to healthier eating. This paper addresses three questions. First, what factors explain SNAP participation of low-income individuals in addition to basic income eligibility requirements? Second, does SNAP participation increase fruit and vegetable consumption? Third, what effect does the Supplemental Nutrition Assistance Program Education (SNAP-Ed) in Arizona have on fruit and vegetable consumption for low-income households? The data used in this study were drawn from two waves of the Arizona Behavioral Risk Factor Surveillance System survey. The study found people in Arizona ate fruits, on average 1.4 times per day and vegetables 1.6 times per day. Marital and household arrangement status significantly affected both SNAP participation and fruit and vegetable consumption, but effects for men and women differed. Distance from services assisting with SNAP enrollment appeared to have no negative effect on eligible respondent enrollment. People living in counties with more SNAP-Ed contractors per person below 125% of the poverty line consumed more fruits and vegetables, but the effect was only marginally significant. Future research should consider more geographically specific measures of SNAP-Ed reach.