The design and analysis of single flank transmission error testor for loaded gears

Due to geometrical imperfections in gears and finite tooth stiffnesses, the motion transmitted from an input gear shaft to an output gear shaft will not have conjugate action. In order to strengthen the understanding of transmission error and to verify mathematical models of gear transmission error, a test stand that will measure the transmission error of a gear pair at operating loads, but at reduced speeds would be desirable. This document describes the design and development of a loaded transmission error tester. For a gear box with a gear ratio of one, few tooth meshing combinations will occur during a single test. In order to observe the effects of different tooth mesh combinations and to increase the ability to load test gear pairs with higher gear ratios, the system was designed around a gear box with a gear ratio of two

Fuel injector characterization studies

The atomization of several general aviation piston engine manifold port fuel injectors was investigated. The injectors were installed in a test rig and operated under simulated conditions. Laser interferometric techniques were used to optically probe the spray droplet fields for droplet size and velocity at numerous spatial locations throughout the field

Analysis and testing of a new method for drop size measurement using laser scatter interferometry

Research was conducted on a laser light scatter detection method for measuring the size and velocity of spherical particles. The method is based upon the measurement of the interference fringe pattern produced by spheres passing through the intersection of two laser beams. A theoretical analysis of the method was carried out using the geometrical optics theory. Experimental verification of the theory was obtained by using monodisperse droplet streams. Several optical configurations were tested to identify all of the parametric effects upon the size measurements. Both off-axis forward and backscatter light detection were utilized. Simulated spray environments and fuel spray nozzles were used in the evaluation of the method. The measurements of the monodisperse drops showed complete agreement with the theoretical predictions. The method was demonstrated to be independent of the beam intensity and extinction resulting from the surrounding drops. Signal processing concepts were considered and a method was selected for development

Evaluation and application of a new interferometry technique for compressible flow research

A new method for obtaining large scale interferograms of flow fields in real time was investigated. The method was based on the point diffraction interferometry technique. The method was modified to accommodate the higher laser power required in recording transonic and supersonic flow fields. Basic tests were conducted in unsteady flows and flows about circulation control airfoils at transonic speeds. It was found that vibration was not a significant factor in the application of the system. In the case of the circulation control airfoils, the real-time viewing allowed the identification of the Coanda jet interaction with the external flow and the shedding of large scale vortices. The method proved to be very sensitive to the optical quality of the wind tunnel windows. The results obtained were compared with earlier interferograms obtained using interferometry. These results were in qualitative agreement

Conveyance of Real Estate - Parol Gift of Land - Statute of Frauds

The Pennsylvania Supreme Court has held that an alleged parol gift of land between blood relatives lacked immediate donative intent and a clear and unambiguous acceptance, where the donee rejected conveyances of the same property, because of issues collateral to the gift and independent of the disputed property interest. Fuisz v Fuisz, 527 Pa 348, 591 A2d 1047 (1991)

Promises and lies: Can observers detect deception in written messages

Abstract: We design a laboratory experiment to examine predictions of trustworthiness in a novel three-person trust game. We investigate whether and why observers of the game can predict the trustworthiness of hand-written communications. Observers report their perception of the trustworthiness of messages, and make predictions about the senders’ behavior. Using observers’ decisions, we are able to classify messages as “promises” or “empty talk.” Drawing from substantial previous research, we hypothesize that certain factors influence whether a sender is likely to honor a message and/or whether an observer perceives the message as likely to behonored: the mention of money; the use of encompassing words; and message length. We find that observers have more trust in longer messages and “promises”; promises that mention money are significantly more likely to be broken; and observers trust equally in promises that do and do not mention money. Overall, observers perform slightly better than chance at predicting whether a message will be honored. We attribute this result to observers’ ability to distinguish promises from empty talk, and to trust promises more than empty talk. However, within each of these two categories, observers are unable to discern between messages that senders will honor from those that they will not

Broken Contracts and Hidden Partnerships: Theory and Experiment

Previous research indicates that unenforceable informal contracts (or commit- ments) promote trust and reciprocity. Nonetheless, while such contracts may benefit existing exchange, in dynamic environments they may also hinder ones willingness to explore newly emerging Pareto efficient opportunities. This issue arises in both business and social contexts, and includes industry non-compete agreements as well as personal relationship commitment decisions. We report data from an experiment using a novel three-person trust game where, in differ- ent treatments, different players are able to communicate with each other. We find that when, between the point of commitment and the point of decision, no new information is received regarding the expected value of commitment, then people overwhelmingly decide in accord with their informal contracts and avoid exploring potentially Pareto improving opportunities. However, when new in- formation arises that reduces the relative value of commitment, and when this occurs following the commitment but before the decision, then people are signif- icantly more likely to deviate from their informal contract and pursue a Pareto improvement. Further, we observe a contingency effect where the likelihood with which people follow an informal commitment declines with the number of contin- gencies that must occur in order for the contract to be realized. Finally, none of the theories of lying aversion that we explore are able fully to explain our data