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- Title
- Design and Evaluation of End Effectors and an Indoor Simulated Orchard Environment for Robotic Apple Harvesting
- Creator
- Dickinson, Nathan
- Date
- 2022
- Collection
- Electronic Theses & Dissertations
- Description
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A recently developed vacuum-based harvesting robot has shown promise in picking fruit from clusters, providing better access to tree canopies and minimizing fruit bruising. One of the main technical issues for this harvesting robot is the design of an end effector that can effectively grip the fruit for detachment. Field fruit picking studies using manual straight pull and twisting picking methods were first conducted for three varieties of apple. The critical pulling force and torque needed...
Show moreA recently developed vacuum-based harvesting robot has shown promise in picking fruit from clusters, providing better access to tree canopies and minimizing fruit bruising. One of the main technical issues for this harvesting robot is the design of an end effector that can effectively grip the fruit for detachment. Field fruit picking studies using manual straight pull and twisting picking methods were first conducted for three varieties of apple. The critical pulling force and torque needed to detach 95% of apples were determined to be 28.3 N and 0.257 N-m (equivalent suction force of 21.0 N for the current robot’s vacuum tube). Three new conformable silicone end effectors with different configurations (i.e., “Straight”, “Bellow”, and “Curved”) were designed and fabricated to provide more effective air sealing, and thus lower vacuum pressure for increased gripping force to effectively detach fruit compared to the robot’s original end effector. Laboratory and field picking performance studies with the harvesting robot showed that all three new end effectors performed significantly better than the original, non-conformable end effector. The straight end effector achieved 87% picking success rate; performing consistently better than the other two new end effectors based on multiple performance metrics, and hence should be used in further development of the robotic harvesting system. To enhance robotic harvest research, an indoor simulated orchard environment was constructed, which allows to mimic real fruit picking processes by using artificial trees embedded with specially designed tree branches and magnetic artificial stems for use with real fruit and a unique light system that can simulate different natural lighting conditions for different times of day.
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- Title
- HERD- LEVEL VARIABLES ASSOCIATED WITH ANTIMICROBIAL USE IN THE DAIRY HERDS
- Creator
- Said, Fuaad
- Date
- 2022
- Collection
- Electronic Theses & Dissertations
- Description
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The aim of this study was to identify variables associated with antimicrobial drug use for bovine mastitis. Intramammary tubes used for lactating cows, discarded by farm personnel, were collected in dedicated trash bins for 12 months on each of 104 herds (Michigan n = 49, Pennsylvania n = 55). Antimicrobial use was quantified using two metrics: arithmetic (number of discarded tubes) and defined daily dose (DDD) per 1,000 cow-days. Mastitis control practices, attitudes, and behaviors were also...
Show moreThe aim of this study was to identify variables associated with antimicrobial drug use for bovine mastitis. Intramammary tubes used for lactating cows, discarded by farm personnel, were collected in dedicated trash bins for 12 months on each of 104 herds (Michigan n = 49, Pennsylvania n = 55). Antimicrobial use was quantified using two metrics: arithmetic (number of discarded tubes) and defined daily dose (DDD) per 1,000 cow-days. Mastitis control practices, attitudes, and behaviors were also collected using a survey of herd owners and managers conducted during herd visits. Additionally, a human resources questionnaire survey about dairy producers/manager’s beliefs and practices regarding employee communications, training, and education was also collected for each herd. Across all herds, intramammary tube use based on arithmetic count was 4.43 tubes per1,000 cow-days and 3.52 per 1,000 cow-days based on DDD. A higher trend of antimicrobial use (5.22 tubes per 1,000 cow-days and DDD of 4.1 per 1,000 cow-days) was found in Pennsylvania than in Michigan (3.61 tubes per1000 cow-days and the DDD 2.91 per 1,000/ cow-days). Ranking of antimicrobial use showed that ceftiofur was the most frequently used antimicrobial in the study, followed by cephapirin, pirlimycin, amoxicillin, hetacillin, and cloxacillin. A majority of producers believed that they had sufficient knowledge of mastitis treatment and control, but only 23% of them had a written treatment protocol, and less than half of them (44%) reviewed animal health? History before treating infected cows. Moreover, 80% disagreed that culture of milk samples is needed to make mastitis treatment or management decisions. Multivariate models had similar results, regardless of the metric used to determine intramammary drug use; there was a positive correlation between drug use and the new subclinical mastitis rate (based on monthly DHI SCC testing) and the producer’s willingness to improve the image of the dairy products. Use of natural remedies for mastitis treatment was negatively correlated with intramammary drug use. Our results indicate that there continues to be a gap between producer practices and beliefs and best practices to reduce antimicrobial use on dairy farms. Also, intramammary drug use is highly associated with the dynamics of subclinical mastitis as measured in individual cows, and a herd average level.
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- Title
- EMERGENT COORDINATION : ADAPTATION, OPEN-ENDEDNESS, AND COLLECTIVE INTELLIGENCE
- Creator
- Bao, Honglin
- Date
- 2022
- Collection
- Electronic Theses & Dissertations
- Description
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Agent-based modeling is a widely used computational method for studying the micro-macro bridge issue by simulating the microscopic interactions and observing the macroscopic emergence. This thesis begins with the fundamental methodology of agent-based models: how agents are represented, how agents interact, and how the agent population is structured. Two vital topics, the evolution of cooperation and opinion dynamics are used to illustrate methodological innovation. For the first topic, we...
Show moreAgent-based modeling is a widely used computational method for studying the micro-macro bridge issue by simulating the microscopic interactions and observing the macroscopic emergence. This thesis begins with the fundamental methodology of agent-based models: how agents are represented, how agents interact, and how the agent population is structured. Two vital topics, the evolution of cooperation and opinion dynamics are used to illustrate methodological innovation. For the first topic, we study the equilibrium selection in a coordination game in multi-agent systems. In particular, we focus on the characteristics of agents (supervisors and subordinates versus representative agents), the interactions of agents (reinforcement learning in the games with fixed versus adaptive learning rates according to the supervision and time-varying versus supervision-guided exploration rates), the network of agents (single-layer versus multi-layer networks), and their impact on the emergent behaviors. Regarding the second topic, we examine how opinions evolve and spread in a cognitively heterogeneous agent population with sparse interactions and how the opinion dynamics co-evolve with the open-ended society's structural change. We then discuss the rich insights into collective intelligence in the two proposed models viewed from the interaction-based adaptation and open-ended network structure. We finally link collective emergent intelligence to diverse applications in the realm of computing and other scientific fields in a cross-multidisciplinary manner.
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- Title
- A MORAL PERSPECTIVE ON GUILT APPEALS : EXAMINING THE MORAL MATCHING EFFECT
- Creator
- Ye, Qijia
- Date
- 2022
- Collection
- Electronic Theses & Dissertations
- Description
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As a moral emotion, guilt can serve as a mechanism in social influence. However, literature showed that the effects of guilt appeals were mixed. This indicates that scholars scarcely understand the conditions under which guilt appeals work effectively. Drawing from Moral Foundation Theory (Graham et al., 2013), this study investigated the moderating role of moral foundations in guilt appeals. I argued that the match between the transgression focus of a guilt appeal and an endorsed moral...
Show moreAs a moral emotion, guilt can serve as a mechanism in social influence. However, literature showed that the effects of guilt appeals were mixed. This indicates that scholars scarcely understand the conditions under which guilt appeals work effectively. Drawing from Moral Foundation Theory (Graham et al., 2013), this study investigated the moderating role of moral foundations in guilt appeals. I argued that the match between the transgression focus of a guilt appeal and an endorsed moral foundation would increase the intensity of perceived guilt and reduce psychological reactance, thereby leading to a more positive attitude and stronger behavioral intention. A single factorial (care/harm guilt appeal vs. purity/degradation guilt appeal vs. liberty/oppression guilt appeal vs. control message) between-subject experiment was conducted to test the moral matching effect in the context of reducing children’s consumption of sugary drinks. Results showed that care-focused guilt appeal elicited more guilt and less psychological reactance than purity-focused and liberty-focused guilt appeals. More importantly, the purity foundation mitigated the negative effect of purity-focused guilt appeal on psychological reactance, particularly on anger. The explanations for the findings, theoretical and practical implications, limitations of the study, and future research directions were discussed.
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- Title
- OPPORTUNITIES AND CHALLENGES OF INTEGRATED LARGE SCALE PFAS MODELING
- Creator
- Raschke, Anna
- Date
- 2022
- Collection
- Electronic Theses & Dissertations
- Description
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Perfluoroalkyl substances (PFAS) have been observed around the world in air, water, and soil. Recent research and monitoring studies have alluded to the widespread presence of PFAS, but most observe the impact of PFAS as a snapshot in time and space. In an effort to better understand PFAS fate and transport in the environment, computational models have been developed. For this study, we synthesized the model applications of PFAS fate and transport via water medium through surface water,...
Show morePerfluoroalkyl substances (PFAS) have been observed around the world in air, water, and soil. Recent research and monitoring studies have alluded to the widespread presence of PFAS, but most observe the impact of PFAS as a snapshot in time and space. In an effort to better understand PFAS fate and transport in the environment, computational models have been developed. For this study, we synthesized the model applications of PFAS fate and transport via water medium through surface water, vadose zone, groundwater, streamflow, as well as their uptake and accumulation in plants and aquatic organisms. In addition, the system under this study is permeable to incoming (sources) and outgoing (sinks) PFAS compounds. Ultimately, knowledge gaps in modeling PFAS for each subsystem (e.g., surface water) area were identified. From there, a case study was performed to highlight the shortcomings of widely used models for PFAS fate and transport within a large and complex watershed. With a large number of PFAS using industries, Michigan is at the forefront of PFAS sampling. Therefore, the study area chosen was the Huron River watershed, a highly PFAS impacted watershed in Southeastern Michigan. The results showed the importance of organized monitoring studies and model improvements to better understand PFAS fate and transport in a large watershed.
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- Title
- EFFECT OF HUMAN CHORIONIC GONADOTROPIN (hCG) POST-OVULATION ON TIME TO CONCEPTUS ATTACHMENT IN LACTATING DAIRY COWS
- Creator
- Da Mota Santos, Alisson
- Date
- 2022
- Collection
- Electronic Theses & Dissertations
- Description
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Increasing progesterone (P4) during conceptus development is crucial for establishment of pregnancy in dairy cattle. We developed a robust technique to estimate d of conceptus attachment (CA) based on daily within-cow changes in concentrations of pregnancy-specific protein B (PSPB; BioPRYN). Highest sensitivity and specificity were obtained with a 12.5% increase in addition to 2 consecutive d of continuous increases when predicting CA. We hypothesized that increasing serum P4 post-ovulation...
Show moreIncreasing progesterone (P4) during conceptus development is crucial for establishment of pregnancy in dairy cattle. We developed a robust technique to estimate d of conceptus attachment (CA) based on daily within-cow changes in concentrations of pregnancy-specific protein B (PSPB; BioPRYN). Highest sensitivity and specificity were obtained with a 12.5% increase in addition to 2 consecutive d of continuous increases when predicting CA. We hypothesized that increasing serum P4 post-ovulation would favor embryonic development and reduce time to CA in lactating dairy cows. The first objective was to determine the effects of treatment with hCG on d2, d5, and d2 and 5 post-ovulation on luteal function and serum P4. Treatment with hCG on d 2 & 5 or on d 5 increased P4 by inducing accessory CL (aCL) and increasing the volume of existing CL. On d 2, hCG increased P4 on d 5 post-ovulation. The second objective was to investigate the effects of treatment with hCG on time to CA. Treatment on d 5 reduced the percentage of cows with CA and increased time to CA. Primiparous cows benefited from ipsilateral aCL against pregnancy loss before d 100 post-AI/ovulation. Delayed time to CA was associated with pregnancy losses before d 35. The highest quartile of P4 on d 5, but not on d 19 & 20, was associated with reduced time to CA. Our hypothesis was not confirmed. Yet, early serum P4, but not late, was associated with time to conceptus attachment in multiparous dairy cows. Our findings indicated that treatment with hCG post-ovulation was not financially advantageous as treatment on d 5 or aCL induced by treatment reduced annual herd profits compared to standard reproductive programs such as Double-Ovsynch and Ovsynch.
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- Title
- A PILOT STUDY OF WEB-BASED INFORMATION BOTTLENECK IDENTIFICATION IN AEC PROJECTS
- Creator
- Pandey, Nishchhal Nihal
- Date
- 2022
- Collection
- Electronic Theses & Dissertations
- Description
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The success of the Architecture, Engineering, and Construction (AEC) project relies heavily on the effective communication and information exchange between project team members. A prominent reason for delays and progress shortcomings in AEC project teams is information bottlenecks, defined as missing project information bits which can be due to large influx of information or inadvertent withholding of information at a particular time. Information bottlenecks both in planning and execution...
Show moreThe success of the Architecture, Engineering, and Construction (AEC) project relies heavily on the effective communication and information exchange between project team members. A prominent reason for delays and progress shortcomings in AEC project teams is information bottlenecks, defined as missing project information bits which can be due to large influx of information or inadvertent withholding of information at a particular time. Information bottlenecks both in planning and execution phases of the project tend to cause schedule delays and cost overruns. Information and communication exchange patterns between project team members shed a light on the possible occurrence of information bottlenecks. Recent literature efforts have focused on use of software programming and key performance indicators (KPIs) to identify which phases of project are prone to occurrence of bottlenecks. One of the roadblocks in implementing majority of bottleneck identification techniques in AEC projects is the difficulty in execution. Some of the metrics defined are too complex and require rigorous manual calculations. Given the complexity and feasibility difficulties of the present methodologies for identification of bottleneck, this study aims to contribute to the body of knowledge by providing an adaptable tool that aims to improve the accuracy and practicality for predicting bottlenecks. Therefore, the research question this research aims to answer is “Can the usability and adaptability of information bottleneck prediction in AEC projects be improved through a web-based tool?”Expanding on Lean Construction concepts, key performance indicators (KPIs), efficiency, quantification metrics are developed to study the trends of information shared between AEC project team members. The developed model is semi-automated and reads data by importing the Microsoft Excel sheet which has all the raw project documentation data. A Python code developed by the researcher is used to extract information from the excel, create a dashboard, and publish information bottleneck calculations through a web-based tool. Statistical inferences drawn from the model are then be used to identify occurrence of project bottlenecks. The web-based platform is designed to cater the specific information exchange trends in a typical project. Providing visual representations, and explanations further ease the understanding of the root issue. Finally, through two expert interviews, the web tool is revised, and final tool is presented, and future directions of work are discussed.
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- Title
- THE ROLE OF PREZYGOTIC SELF-COMPATIBILITY IN FACILITATING INTERSPECIFIC COMPATIBILITY IN SOLANUM SECTION PETOTA
- Creator
- Behling, William
- Date
- 2022
- Collection
- Electronic Theses & Dissertations
- Description
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Domesticated potato (Solanum tuberosum L.) is the fourth most important food crop worldwide and critical food security crop. The high significance of this crop coupled with high production losses place potato at a high priority for genetic improvement, especially in the face of climate change. Potato breeding is undergoing a seismic shift from a tetraploid outcrossing crop towards a F1 hybrid system using diploid inbred lines as parents. This transformation has also changed how potato...
Show moreDomesticated potato (Solanum tuberosum L.) is the fourth most important food crop worldwide and critical food security crop. The high significance of this crop coupled with high production losses place potato at a high priority for genetic improvement, especially in the face of climate change. Potato breeding is undergoing a seismic shift from a tetraploid outcrossing crop towards a F1 hybrid system using diploid inbred lines as parents. This transformation has also changed how potato breeders access important traits from wild species. Pre- and post-zygotic barriers, such as self-incompatibility (SI) and endosperm failure, inhibit and complicate the use of the more valuable wild species in conventional and diploid breeding schemes. Traditionally plant breeders have employed the SC x SI rule, using self-compatibility (SC) to increase the success of interspecific crosses. In order to evaluate the potential of several different SC factors in facilitating broad interspecific compatibility: Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)-Cas9 knockout (KO) lines of S-RNase, HT-B and HT-B + S-RNase in S. tuberosum were evaluated along with the self-compatible species S. verrucosum, and S-locus inhibitor gene (Sli) from S. chacoense. Findings confirm the central role of S-RNase in interspecific pollination barriers and the inconsequential role of HT-B alone. Sli had no effect on interspecific barriers despite its prominent role as a source of SC. Finally, S. verrucosum styles displayed an absence of prezygotic barriers. Further analysis of the role of HT-A, as well as other mechanisms that potentially underlie the SC phenotype in S. verrucosum will further clarify the role of specific genetic factors that regulate interspecific compatibility in Solanum section Petota
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