6,029 research outputs found
Control of a flexible beam using fuzzy logic
The goal of this project, funded under the NASA Summer Faculty Fellowship program, was to evaluate control methods utilizing fuzzy logic for applicability to control of flexible structures. This was done by applying these methods to control of the Control Structures Interaction Suitcase Demonstrator developed at Marshall Space Flight Center. The CSI Suitcase Demonstrator is a flexible beam, mounted at one end with springs and bearing, and with a single actuator capable of rotating the beam about a pin at the fixed end. The control objective is to return the tip of the free end to a zero error position (from a nonzero initial condition). It is neither completely controllable nor completely observable. Fuzzy logic control was demonstrated to successfully control the system and to exhibit desirable robustness properties compared to conventional control
Neural networks as a control methodology
While conventional computers must be programmed in a logical fashion by a person who thoroughly understands the task to be performed, the motivation behind neural networks is to develop machines which can train themselves to perform tasks, using available information about desired system behavior and learning from experience. There are three goals of this fellowship program: (1) to evaluate various neural net methods and generate computer software to implement those deemed most promising on a personal computer equipped with Matlab; (2) to evaluate methods currently in the professional literature for system control using neural nets to choose those most applicable to control of flexible structures; and (3) to apply the control strategies chosen in (2) to a computer simulation of a test article, the Control Structures Interaction Suitcase Demonstrator, which is a portable system consisting of a small flexible beam driven by a torque motor and mounted on springs tuned to the first flexible mode of the beam. Results of each are discussed
Oviposition and Development of Emerald Ash Borer \u3ci\u3e(Agrilus Planipennis)\u3c/i\u3e (Coleoptera: Buprestidae) on Hosts and Potential Hosts in No-Choice Bioassays
Emerald ash borer (Agrilus planipennis Fairmaire) (Coleoptera: Bupres- tidae) is an invasive phloem-feeding pest native to Asia. It was first identified in North America in 2002 and has killed millions of ash (Fraxinus spp.) trees in southeast Michigan and Essex County, Ontario. Since then, additional populations have been discovered across Michigan and in areas of Ohio, Indiana, Illinois, Maryland, Pennsylvania and West Virginia. In Asia, A. planipennis reportedly colonizes other genera, including species of Juglans, Pterocarya and Ulmus. In North America, attacks on non-ash species have not been observed but there is concern about host switching as ash mortality progresses. From 2003 to 2005, we evaluated A. planipennis oviposition and larval development on 4 North American ash species: green ash (F. pennsylvanica Marshall), white ash (F. americana L.), black ash (F. nigra Marshall), blue ash (F. quadrangulata Michaux), and 6 potential alternate hosts including privet (Ligustrum and Forestiera spp.), Japanese tree lilac (Syringa reticulate (Blumb) Hara), American elm (Ulmus americana L.), black walnut (Juglans nigra L.), hickory (Carya ovata (Miller) K. Koch) and hackberry (Celtis occidentalis L.). In no- choice tests using cut branches in cages, female A. planipennis oviposited on all species tested. Larvae on green ash, white ash, black ash, blue ash and privet developed to the second instar before branches desiccated. Larvae attempted to feed on some black walnut, Japanese tree lilac, American elm and hackberry branches but died as first instars. There were no feeding attempts on hickory branches. We also conducted no-choice tests by placing adult A. planipennis in cages that encircled the lower 1 m of the trunk of live green ash, white ash, black walnut and Japanese tree lilac nursery trees. High densities of larvae developed on green ash and white ash nursery trees but there was no evidence of any larval survival, feeding, or development on the Japanese tree lilac or black walnut nursery trees
Phase Space Reconstruction and Nonlinear Equilibrium Dynamics in the United States Beef Market
This paper investigates dynamic interactions in the US beef market using phase space reconstruction, which has been developed to analyze nonlinear dynamical systems. This approach provides important and unique empirical insights into consumers behavior in the beef market. Our results from a phase space reconstruction analysis demonstrate distinct differences between intertemporal short run impacts from food safety outbreaks (e.g., E. Coli) and longer run health effects (e.g., cholesterol). Adjustments due to factors such as cholesterol are permanent changes and do not affect the manner by which people consume, while consumers react to food safety scares by adjusting consumption for a short period of time and then returning to their normal steady state cycle of consumption.nonlinear time series, phase space reconstruction, food safety, health effects, Livestock Production/Industries, Marketing,
Spectroscopic Studies of Metal-Cyanide Complexes
Part 1: Infrared and Visible Absorption Studies of Cyanide Complexes of Ni(II) in Aqueous Solution
Part 2: An Analysis of the Infrared Vibrational Spectra of the Tetracyanonickelate(II) Ion in the Solid State
In this work, further evidence has been collected establishing the existence of a new ionic species in solutions of sodium tetracyanonickelate(II) and sodium cyanide. Contrary to the literature, however, this work shows that the species is [Ni(CN)5]-3 rather than [Ni(CN)6]-4
Undergraduate Session I: Presentation 4 - Social Media: A Danger to Adolescent Mental Health
A review of research done on how social media dangers the mental health of adolescents and may influence the development of low self-esteem, anxiety, depression, substance abuse, eating disorders, and suicide
The intellectual and moral integrity of bioethics: response to commentaries on A case study in unethical transgressive bioethics: \u27Letter of concern from bioethicists\u27 about the prenatal administration of dexamethasone .
In our target article we showed that the Letter of Concern (LoC) fails to meet accepted standards for presenting empirical data for the purpose of supplementing a normative claim and for argument-based normative ethics. The LoC fails to meet the standards of evidence-based reasoning by making false claims, failing to reference data that undermine its key premises, and misrepresenting and misinterpreting the scientific publications it selectively references. The LoC fails to meet the standards of argument-based reasoning by treating as settled matters what are, instead, ongoing controversies, offering “mere opinion” as a substitute for argument, and making contradictory claims. The LoC is methodologically defective and thus a case study in unethical transgressive bioethics. Not withdrawing the LoC will damage the field of bioethics, making this case study in unethical transgressive bioethics important for the entire field
Feeling the Stones: Measuring the Potential of Deposit Insurance in China through a Comparative Analysis
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