Most automotive powertrain parts made of castings have surface defects such as pores. However, detecting pores inside small diameter bores is a challenge because of the limited dimensional accessibility. Adding to this difficulty is the auto industry's desire to conduct the porosity inspection in-line, i.e. within the machining production cycle time of a part. A technique or equipment that meets these requirements currently does not exist. In order to meet these demands, it is necessary to develop an entire new methodology to inspect the inner surface of small diameter bores. This paper presents an innovative methodology to inspect the porosity of the inner surface of small bores and to provide their characteristics such as size and location. A prototype measurement system was built and tested in the lab. Experimental results showed the proposed method to be reliable and consistent.
Hong E, Gurel Kazanci F, Prinz AA. Different roles of related currents in fast and slow spiking of model neurons from two phyla. J Neurophysiol 100: 2048 -2061, 2008. First published August 20, 2008 doi:10.1152/jn.90567.2008. Neuronal activity arises from the interplay of membrane and synaptic currents. Although many channel proteins conducting these currents are phylogenetically conserved, channels of the same type in different animals can have different voltage dependencies and dynamics. What does this mean for our ability to derive rules about the role of different types of ion channels in neuronal activity? Can results about the role of a particular channel type in a particular type of neuron be generalized to other neuron types? We compare spiking model neurons in two databases constructed by exploring the maximal conductance spaces of two models. The first is a model of crustacean stomatogastric neurons, and the second is a model of rodent thalamocortical neurons, but both models contain similar types of membrane currents. Spiking neurons in both databases show distinct fast and slow subpopulations, but our analysis reveals that related currents play different roles in fast and slow spiking in the stomatogastric versus thalamocortical neurons. This analysis involved conductance-space visualization and comparison of voltage traces, current traces, and frequency-current relationships from all spiker subpopulations. Our results are consistent with previous work indicating that the role a membrane current plays in shaping a neuron's behavior depends on the voltage dependence and dynamics of that current and may be different in different neuron types depending on the properties of other currents it is interacting with. Conclusions about the function of a type of membrane current based on experiments or simulations in one type of neuron may therefore not generalize to other neuron types.
A novel sensitivity improving method for simultaneously measuring five-degree-of-freedom errors of a moving linear stage is proposed based on collimator and interferometry techniques. The measuring principle and parameters of the system are analyzed theoretically. The experimental results proved that the resolution of the linear displacement of the proposed method has twice that of the current linear interferometer, and the resolutions of the two-dimensional straightness error measurement can be improved by a factor of 8 compared with the movement of the retroreflector itself by using multireflection and lens magnification. The resolutions of the pitch and yaw angular error measurement have been improved by a factor of 10 compared with the rotation of the plane mirror itself by using expander lenses. The whole measuring system is characterized of simple structure, small volume, and high precision. The moving component of the measurement system is wireless, which eliminates the errors and inconvenience introduced by the wire connection. Calibration and comparison tests of this system compared with Renishaw laser interferometer system have been carried out. Experimental results show good consistency for measuring a linear guide way.
A low cost and high precision system which can measure two-degrees-of-freedom straightness simultaneously is proposed based on a laser collimator. In the system, a miniature fiber coupled diode laser generates a collimating beam. The sensitivity of the straightness error measurement is magnified by a factor of 4 compared with the lateral movement of the retro-reflector itself after the multi-reflections. A Renishaw ML10 laser interference measurement system was used to verify the developed system in a series of experiments in the laboratory environment. Experimental results agree with the expected results. The two-dimensional straightness error measurement had linear correlativity close to 1 and the standard one-to-one deviation error was better than 0.32 µm obtained over a travel range of 600 µm.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.